NASDAQ: ENGNW

Overview

We are a clinical-stage biotechnology company mainstreaming genetic medicine through the delivery of therapeutics to mucosal tissues and other organs, with the goal of creating new ways to address diseases with high clinical needs, beginning with non-muscle invasive bladder cancer (NMIBC). We are developing non-viral genetic medicines based on our novel and proprietary dually derived chitosan, or “DDX”, gene delivery platform, which allows localized delivery of complex genetic cargos directly to mucosal tissues and other organs. Our lead product candidate, detalimogene voraplasmid, or detalimogene, formerly known as EG-70, is a therapy designed to promote a pro-inflammatory, anti-tumor microenvironment throughout the bladder urothelium. We believe this enables the immune system to durably clear the tumor and develop memory to resist recurrence. Because this treatment is designed to work by delivering genetic cargo to the broader tumor tissue environment rather than tumor cells specifically, we believe it has the potential to be utilized across a variety of tumor types. Currently, we are developing detalimogene as a monotherapy to treat non-muscle invasive bladder cancer (“NMIBC”) with carcinoma in situ (“CIS”) with or without concomitant papillary disease in patients that have been unresponsive to treatment with Bacillus Calmette-Guérin, or “BCG,” or what is referred to as “BCG-unresponsive NMIBC with CIS.” BCG is established as the first-line therapy for patients diagnosed with high-risk NMIBC; however, supply constraints have resulted in a shortage of BCG in the United States for over a decade. We are also exploring the clinical application of detalimogene to various additional NMIBC patient populations, namely, high-risk papillary-only BCG-unresponsive NMIBC (i.e., high-risk NMIBC without CIS), as well as high-risk BCG-naïve NMIBC patients with CIS and high-risk BCG-exposed NMIBC patients with CIS (i.e., patients who have not received an adequate course of BCG and who do not qualify as BCG-unresponsive in accordance with FDA and urology practice guidelines).

In NMIBC, carcinoma in situ, or CIS, is a flat, high-grade tumor that can invade the deeper layers of the bladder wall if left untreated. A “high-” or “low-” tumor risk describes the degree to which the tumor pathology appears more likely to grow quickly and invade non-cancerous tissue. NMIBC with CIS, which is high-risk, is typically initially treated with a solution containing the bacterium BCG that is instilled into the bladder multiple times over the course of several months. Despite high initial response rates to this treatment, many of these patients will experience a recurrence that is unresponsive to additional BCG, allowing the cancer to spread throughout, and deeper into, the bladder, often requiring surgical removal of the bladder (this procedure is called a radical cystectomy). We believe patients with BCG-unresponsive NMIBC with CIS are currently underserved with limited FDA-approved treatment options, and that there is a market opportunity for detalimogene as a monotherapy for patients with this condition. While the potential market for detalimogene may not ultimately be limited to these patients, that is our current initial focus in working to bring detalimogene to market.

Within the United States, we estimate that there are approximately 85,000 new patients each year diagnosed with bladder cancer, of which up to 80% present with non-muscle invasive disease. Bladder cancer also poses a long-term management burden with an estimated 730,000 people living with disease. See “— Lead Product Candidate and Pipeline Development — Lead Program: NMIBC Background and Unmet Need” for further information.

Detalimogene is currently being studied in a combined Phase 1/2 open-label trial, referred to as “LEGEND” (ClinicalTrials.gov identifier NCT04752722). The Phase 2 portion of LEGEND is comprised of three cohorts: Cohort 1 is a pivotal cohort studying detalimogene in patients with high-risk BCG-unresponsive NMIBC with CIS with or without concomitant papillary disease for which we have completed enrollment with 125 patients; Cohort 2 is evaluating detalimogene in patients with high-risk BCG-naïve NMIBC with CIS (Cohort 2a, with 30 enrolled patients as of November 11, 2025) and patients with high-risk BCG-exposed NMIBC with CIS

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(Cohort 2b, with 45 enrolled patients as of November 11, 2025); and Cohort 3 is evaluating detalimogene in patients with high-risk BCG-unresponsive NMIBC who have papillary disease only (i.e., no CIS, with 36 enrolled patients as of November 11, 2025). In addition, our preclinical research is focused on expanding the cancer indications that can be treated with detalimogene as well as discovering new opportunities to apply our DDX technology platform to treat other indications with high unmet medical needs.

Our Competitive Strengths

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Detalimogene Product Candidate Demonstrated Compelling Preliminary Data in Phase 2 of LEGEND — We are developing detalimogene, which has received FDA Regenerative Medicines Advanced Therapy (RMAT) and Fast Track designations, as a monotherapy for patients with BCG-unresponsive NMIBC with CIS who we believe are underserved with limited FDA-approved treatment options. In addition, the LEGEND study has been selected for the U.S. Food and Drug Administration’ (“FDA”) Chemistry, Manufacturing, and Controls (“CMC”) Development and Readiness Pilot (“CDRP”) Program. We have released preliminary data from the pivotal arm of the LEGEND study (Cohort 1) on two occasions; the first occasion in which we released Phase 2 LEGEND Cohort c1 data (cut-off date of September 13, 2024) demonstrated that detalimogene was generally well-tolerated across all patients dosed, with no patients experiencing a Grade 3, 4 or 5 treatment-related adverse event (“TRAE”) and no drug-related discontinuations. Based on preliminary data corresponding to the September 13, 2024 data cut-off, detalimogene also demonstrated promising clinical activity. Across 21 patients included in the preliminary data, a 71% complete response rate (“CR” rate) at any time was observed (15/21), along with a 3-month CR rate of 67% (14/21), a 6-month CR rate of 47% (8/17), and a 6-month Kaplan-Meier CR rate estimate of 51%. Our most recent data update (released on November 11, 2025 and reflective of an October 24, 2025 data cut-off) provided an updated view of preliminary activity and tolerability following implementation of a protocol amendment designed to better align LEGEND with the standard of care amongst urological practitioners treating NMIBC with CIS. Among patients treated under the amended protocol, 62% of patients remained in CR at six months after initiation of treatment, with all evaluable patients at nine months also demonstrating continued CR. Detalimogene continued to demonstrate a generally well-tolerated safety profile in Cohort 1, with treatment-related adverse events primarily Grades 1–2 in severity and a limited number of Grade 3 events, and no Grade 4 or Grade 5 TRAEs reported at the time of data cut-off. We believe these updated results illustrate the intended benefits of the protocol amendments.

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Product Profile Tailored to the Practical Needs of Clinicians and Patients — Gene therapy and genetic medicines products, such as oncolytic viruses, have historically been associated with specific handling or dosing requirements designed for safety reasons to minimize patient, physician, or environmental exposure or risk. These can include use of enhanced personal protective equipment during preparation and administration, required virucidal decontamination of drug product-exposed bodily fluids, such as urine, after exposure to the genetic medicine product, preparative treatment of tissues with a solvent or wash agent, enhanced refrigeration/cold chain on-site storage requirements, and guidance to avoid close personal contact with the patient during the treatment period. By contrast, we believe detalimogene can be handled in accordance with biosafety level 1 guidelines, should not require the aforementioned precautions in handling or decontamination of fluids or bodily surfaces following dosing when handled in accordance with most institutional or standardized guidelines, and has no ultra cold chain on-site storage requirements. We believe these product characteristics, among others, will position detalimogene, if approved, as a preferred choice among both physicians and patients.

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“Pipeline-in-a-Product” Potential — Through the combined data generated in the LEGEND study and corresponding preclinical studies, we have demonstrated that detalimogene is able to traverse the mucosal barrier and transfect the underlying epithelial tissues, drive expression of multiple cargos in transfected tissues, and simultaneously activate multiple arms of the immune system. We have further demonstrated in preclinical models the potential for expanding detalimogene to treat solid tumors.

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Scalable, Proprietary Manufacturing Process — We developed the DDX platform in-house, and in addition, have developed manufacturing processes to produce detalimogene that we believe are robust, cost-effective, and scalable. These manufacturing processes, which involve incorporation of plasmid DNA with the DDX carrier at a defined concentration and mixing rate using commercially available equipment, are patent-protected and involve proprietary know-how. We also have a global, royalty-bearing, non-exclusive license to use certain patents and know-how relating to a proprietary plasmid DNA backbone for high-yield production and efficient transgene expression in target tissues. We believe we have scaled up our manufacturing processes to a level that will be able to meet the needs of a potential commercial launch for detalimogene. We believe our manufacturing process is in accordance with current Good Manufacturing Practice (cGMP) and quality system regulations for drugs and biologics.

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Proprietary “Next-Generation” DDX Platform — We believe our DDX platform has the potential to be the next-generation platform that takes genetic medicine beyond rare diseases and into the mainstream of patient care for larger disease indications. The platform has a high degree of payload flexibility, including the ability to conveniently deliver multiple genes (including DNA and RNA) in a single drug product, and has been demonstrated in preclinical animal and in vitro models to effectively induce expression of therapeutic genes in mucosal tissues following delivery to the urinary tract, lung, and gastrointestinal tract, among other organs, all without integration of the genetic cargo into the host’s genomic DNA. We believe products developed using the DDX platform can overcome many of the significant challenges that have historically faced genetic medicines, including immunogenicity, safety concerns, limited efficacy, high cost of goods, lack

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of commercially viable manufacturing technology, limited ability to effectively target localized diseases, systemic toxicity, and difficulties with effective administration.

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Experienced Management Team — Our management team has extensive experience across oncology, urology and multiple other therapeutic areas and modalities and is well-equipped to lead our drug development and commercialization efforts.

Our Strategy

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Focus on advancing our lead product candidate detalimogene through late-stage clinical development and seek regulatory marketing approval in the United States. We are focused on bringing detalimogene to market as a monotherapy for patients with BCG-unresponsive NMIBC with CIS who we believe are currently underserved by the recommended standard-of-care of radical cystectomy, a major surgery that carries a high mortality rate, a reduced quality of life, and other significant negative clinical outcomes. In response to this urgent unmet need, the FDA has issued guidance and subsequently updated and maintained this guidance for the design of clinical studies for development of novel NMIBC treatments for patients with CIS who are unresponsive to BCG, with a goal of encouraging development of alternative treatments to this drastic surgery. We have followed this guidance and discussed our detalimogene development plan with the FDA and, after these discussions, the FDA cleared us to initiate the Phase 2 portion of the LEGEND clinical trial, including the pivotal portion (Cohort 1). We currently plan to file a Biologics License Application (“BLA”) with the FDA in the second half of 2026 for approval to market detalimogene in the United States as a monotherapy for BCG-unresponsive NMIBC with CIS, and we believe detalimogene’s product profile will integrate seamlessly into community urology clinics where the vast majority of urologists practice.

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Build a fully integrated company by independently commercializing approved products in indications and key geographies where we believe we can maximize the value of detalimogene and any other product candidates we develop. We currently own all development and commercialization rights for our detalimogene. To bolster our potential return on investment, we currently plan to retain commercial rights to detalimogene in the United States and to commercialize detalimogene independently, while selectively partnering outside of the United States, with the goal of leveraging a potential partner’s regional expertise and existing sales force to the extent appropriate.

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Explore additional clinical applications of detalimogene within high-risk NMIBC. Given the persistent high unmet need in high-risk NMIBC outside of the BCG-unresponsive population with CIS, the Phase 2 LEGEND trial is also assessing detalimogene in other indications such as BCG-Naïve NMIBC with CIS, BCG-exposed NMIBC with CIS, and BCG-unresponsive, papillary-only NMIBC.

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We believe we can potentially develop detalimogene as a treatment for other forms and stages of bladder cancer, including applications within NMIBC and beyond. For example, we have shown in a murine preclinical orthotopic model of locally advanced bladder cancer that i) administration of detalimogene drives profound and durable anti-tumor immunity, and ii) cured mice exhibit resistance to subsequent local or distal re-challenge with bladder tumor cells due to detalimogene’s potentiation of a T-cell mediated response within the adaptive immune system. These preclinical observations support detalimogene’s immunostimulatory mechanism of action and speaks to its potential in more aggressive or advanced diseases where the bladder remains intact, such as locally advanced or metastatic bladder cancer. We further believe that to the extent detalimogene proves to be both safe and effective in more aggressive, high-risk NMIBC populations, it also will have the potential for use in earlier stage low- and intermediate-risk NMIBC populations.

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Apply our proprietary DDX platform to other mucosal tissues. We believe that our clinical data to date demonstrate the value and breadth of our DDX platform in delivering genetic medicines to mucosal tissues, especially when combined with our preclinical proof-of-concept studies. We believe this could allow us to use our DDX platform to develop safe and effective new agents beyond detalimogene, thereby unlocking better outcomes for historically difficult-to-treat conditions. Our belief is driven by our DDX platform’s numerous advantages and points of differentiation relative to other approaches to genetic medicine, which we believe will enable us to apply such medicines beyond their traditional tissues of application such as the liver, muscle, and central nervous system. Importantly, we have also developed a streamlined, end-to-end cGMP manufacturing process that we believe can support commercial launch of detalimogene and can be readily applied to new drug products.

Lead Product Candidate and Pipeline Development

Our lead product candidate is detalimogene voraplasmid, which we are developing as a monotherapy for the treatment of NMIBC via the LEGEND study, a multi-cohort Phase 2 open-label study comprised of single-arm cohorts (ClinicalTrials.gov identifier NCT04752722). Cohort 1 of LEGEND, which has enrolled BCG-unresponsive NMIBC patients with CIS, is pivotal, and we plan to incorporate the data from this study in a BLA that we plan to submit no later than immediately following the conclusion of the Phase 2 portion of Cohort 1. In addition to this pivotal cohort, LEGEND has two additional cohorts and three patient groups: Cohort 2a is evaluating detalimogene in patients with BCG-naïve NMIBC with CIS; Cohort 2b is evaluating detalimogene in patients with BCG-exposed NMIBC with CIS; and Cohort 3 is evaluating detalimogene in patients with BCG-unresponsive NMIBC who have papillary disease only (i.e., no CIS).

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The following chart shows the enrollment status of each LEGEND cohort as of November 11, 2025, the date of our most recent LEGEND trial update:

All NMIBC cohorts refer to high-risk NMIBC unless otherwise specified.

Detalimogene voraplasmid Mechanism of action

Detalimogene consists of a small plasmid DNA encapsulated in nanoparticles using enGene’s proprietary DDX carrier. These nanoparticles are further coated with a modified polyethylene glycol (PEG) polymer, forming a reversible PEG corona that enhances diffusion through the glycosaminoglycan layer that lines the bladder wall while preserving the particles’ potency. Detalimogene is formulated as an aqueous nanoparticle dispersion in mannitol, then filter-sterilized and lyophilized into a dry powder that can be stably stored under standard refrigeration or freezing conditions.

The DDX delivery vehicle is a novel chemical entity proprietary to enGene. It consists of a highly derivatized short-chain chitosan polymer which complexes with DNA to form consistent nanoparticles. The plasmid DNA drug substance encodes three distinct genes: a single-chain interleukin-12 (IL-12) protein and two non-coding RNAs, eRNA11a and VA1, which together activate the retinoic acid-inducible gene I (RIG-I) pathway. The coordinated effects of IL-12 secretion and RIG-I activation stimulate both innate and adaptive immunity, establishing a pro-inflammatory, tumor-killing environment:

Mechanistically, detalimogene’s dual RIG-I agonists work by initiating a signaling cascade that results in the production of Type I interferons (IFN) and proinflammatory cytokines upon recognizing certain double stranded RNA molecules typically associated with cellular pathogens. This in turn stimulates a potent inflammatory response that results in direct tumor cell killing, cytokine-mediated activation of innate immune cells, and the recruitment and cross-priming of T cells. Detalimogene’s third genetic cargo, IL-12, is an

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immunomodulatory cytokine that signals primarily through the IL-12 receptor complex, which is expressed on natural killer (NK), NK-T, and activated effector CD4+ and CD8+ T cells. For these cells, receptor engagement of IL-12 enhances cytotoxicity, e.g., by driving T cell proliferation, polarization to a type 1 helper (Th1) phenotype, and interferon-gamma (IFNg) production. In summary, the activation of RIG-I is intended to induce an innate immune response that will trigger T cell recruitment and cross-presentation of tumor antigens to T cells through induction of mediators such as C-X-C motif chemokine ligand 10 (CXCL10) and Type I IFNs, respectively. The expression of the IL-12 protein is intended to synergistically augment the anti-tumor activity of indwelling effector T cells. Together, RIG-I agonism and IL-12 receptor stimulation function in a two-step mechanism to recruit and activate immune cells to the tumor microenvironment (“TME”). Importantly, detalimogene does not need to transfect tumor cells specifically to drive the above effects and can exert its anti-tumor effect by transfecting healthy epithelial cells within the tumor or bladder microenvironment. Importantly, we believe restricting expression of IL-12 to the bladder and tumor microenvironment yields meaningful safety advances. This is important as historically, clinical trials using systemic administration of IL-12 to treat various solid malignancies have resulted in severe dose-limiting toxicities, resulting in a marginal therapeutic index. We believe the clinical data observed to date demonstrate that coupling the potent stimulation of the innate immune system by RIG-I agonism and stimulation of the adaptive immune response by IL-12 provides robust and persistent anti-tumor activity.

Lead Program: NMIBC Background and Unmet Need

Disease Background

Bladder cancer represents a serious, life-threatening condition. Based on data reported through 2020, bladder cancer was projected to result in an estimated 2.7% of all cancer deaths in 2023 while comprising an estimated 4.2% of all new cancer cases according to the National Institute of Health. Overall, according to the American Cancer Society and the National Institute of Health, the chance men will develop this cancer during their life is about 1 in 28; for women, the chance is about 1 in 91. Fortunately, due to early warning signals such as hematuria (the presence of blood in the urine), many instances of bladder cancer are diagnosed while still localized to the bladder urothelium. These tumors, referred to as non-muscle invasive bladder cancer (NMIBC), represent approximately 80% of newly diagnosed bladder tumors.

Unmet Medical Need

When diagnosed at the non-muscle invasive stage, the goal of treatment is to prevent further tissue invasion (i.e., into the muscle layers of the bladder or beyond), thereby potentially reducing the intensity of needed treatment regimens (e.g., allowing local/intravesical treatment versus systemic/intravenous treatment), improving disease prognosis, and forestalling surgical bladder removal, if indicated. Since the 1970s, the primary therapy for high-risk NMIBC has been intravesical BCG therapy and/or transurethral resection of bladder tumor surgery (TURBT), despite the adverse effects of both treatment approaches. Due to the increased use of BCG in the high-risk setting and loss of several manufacturers of BCG, supply constraints have resulted in a shortage of BCG for commercial use. To manage the limited supply available in the United States, as of February 2019, the American Urological Association and their collaborative physician groups have introduced rationing guidelines that limit use of BCG to high-risk NMIBC patients only. This situation is projected to continue late into the current decade and has brought urgency to the unmet medical need for effective intravesical treatments for patients with high grade NMIBC, according to the American Urological Association.

We estimate that there are approximately 85,000 new patients each year diagnosed with bladder cancer in the United States, of which up to 80% are initially diagnosed with NMIBC. Within this group, we estimate approximately 30% present with high-risk NMIBC (where risk level describes the risk of disease progression to muscle invasion), 35% present with intermediate-risk disease, and 35% present with low-risk disease. NMIBC lesions are further characterized as CIS, Ta, and T1 based on their physical attributes. Ta and T1 lesions are papillary urothelial carcinomas which have not yet penetrated the muscle wall of the bladder. These tumor types are not mutually exclusive within the bladder; at any given time, an NMIBC patient can have papillary lesions only, CIS and papillary lesions, or CIS lesions only. In general, while most NMIBC patients respond favorably to treatment (e.g., transurethral resection of bladder tumor surgery (“TURBT”) and/or treatment with BCG), it is estimated that as many as 60% will experience a recurrence within one year, depending on the patient and tumor characteristics. For patients with BCG-unresponsive NMIBC, standard therapy has been radical cystectomy or treatment with systemic therapy, both of which have been associated with significant toxicities and complications, including a lower quality of life, and increased treatment-related morbidity and mortality. No salvage medical or intravesical treatments have been shown to have durable efficacy in BCG-unresponsive NMIBC patients and therefore, we believe there is an unmet medical need for novel non-systemic therapies to treat these patients. This recurrent population represents a population of patients with a need to keep their cancer from becoming invasive while being able to preserve their bladders.

Importantly, we believe that the frequency of newly incident high-risk NMIBC per year does not fully capture the number of patients living with this disease. This is because there are multiple channels through which a patient previously diagnosed with low- or intermediate-risk NMIBC may, through the course of their treatment and disease evolution, ultimately present with high-risk disease. For example, a patient whose tumor was initially diagnosed and treated as low- or intermediate-risk NMIBC may recur as high-risk NMIBC. Similarly, a patient treated for BCG-unresponsive high-risk NMIBC with CIS may recur a second time with another high-risk NMIBC lesion and be eligible for another round of treatment. Thus, we believe that the real-world high-risk NMIBC burden is best understood as a combination of both incident and prevalent disease. Unfortunately, for individuals with BCG-unresponsive NMIBC

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with CIS, which represents the focus of LEGEND’s pivotal cohort, FDA-approved non-surgical treatment options are few in number and each suffer from significant limitations.

Study Design

LEGEND is a Phase 1/2, open-label, multicenter global study with a pivotal Phase 2 study cohort focused on adult patients with NMIBC with CIS who have failed BCG therapy. The study consists of two phases, beginning with a (completed) Dose-Escalation Phase (Phase 1). The key objective for the Phase 1 portion of the study was evaluation of safety and tolerability and selection of a dose for the Phase 2 portion, and it was not designed to evaluate efficacy in a statistically meaningful way. While not statistically powered for efficacy, an evaluation of efficacy was a secondary objective, with a Phase 2 study to be conducted at the recommended dose. Eligible patients with BCG-unresponsive NMIBC with CIS were enrolled in Phase 1 and additional patients meeting these criteria were enrolled in Cohort 1 of Phase 2, which has now completed enrollment.

In addition to the pivotal cohort 1, the Phase 2 portion of LEGEND has two additional cohorts: Cohort 2 is evaluating detalimogene in patients with BCG-naïve NMIBC patients with CIS (Cohort 2a) and BCG-exposed NMIBC patients with CIS (Cohort 2b); and Cohort 3 is evaluating detalimogene in patients with BCG-unresponsive NMIBC who have papillary disease only (i.e., no CIS).

Phase 1

The Phase 1 portion of the study was an open-label, multi-dose study designed to evaluate the safety of detalimogene in high-risk BCG-unresponsive NMIBC patients with CIS, with or without co-occurring papillary disease, and to help determine an appropriate dose for the Phase 2 portion of LEGEND. This study enrolled a total of 24 patients across multiple dose groups.

Phase 1 Study Design

All patients in Phase 1 received at least one cycle of treatment with detalimogene. A cycle is 12 weeks or approximately three months in duration, which corresponds to the exploratory three-month efficacy endpoint of the Phase 1 study (see below). Those patients who experience CR or stable disease (“SD”) at the end of the first three-month treatment cycle could (in association and consultation with their physician) optionally elect to continue receiving treatment for up to a total of four cycles, provided they did not have progressive disease (“PD”) on evaluation for response at the end of each cycle. Patients who complete cycle 1 and the additional 3 cycles without PD are followed until PD or for approximately 2 years following their End-of-Treatment Visit, whichever occurs first. In general, we use the terminology “3-month,” “6-month,” “9-month,” and “12-month” timepoint to refer to 12-week, 24-week, 36-week, and 48-week timepoints, respectively. We use these terms interchangeably.

Phase 1 Study Endpoints

The primary endpoint of the Phase 1 study was safety (i.e., characterizing the nature, incidence, relatedness and severity of all observed adverse events (“AEs”) and severe adverse events (“SAEs”)), with complete response at 3 months and pharmacodynamics of biomarkers assessed as exploratory endpoints.

Phase 1 Results: Safety

Twenty-four patients received at least one dose of detalimogene in the Phase 1 study, with the total number of treatment-related adverse events (TRAEs) and most commonly reported TRAEs across all 24 patients defined in the table below. The majority (75%) of TRAEs experienced by patients were Grade 1 or 2 and largely consistent with the same events seen with instrumentation, catheterization, and instillation of any intravesical agent. One Grade 3 TRAE was observed in Phase 1. However, on review, it was observed that the patient had a history of renal failure and recurrent obstructive uropathy prior to treatment that was present at screening, and the enrollment criteria for LEGEND were subsequently modified to exclude patients with similar medical history. There was no association between the severity or incidence of AEs and the dose level. In addition, TRAEs were not more frequent or severe in later cycles of dosing. The following table summarizes the Phase 1 safety results.

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Phase 1 Results: Efficacy

Efficacy at 3 months was assessed by the standard three-criteria efficacy evaluation used for NMIBC, namely urinary cytology, cystoscopic appearance (i.e., an inspection with a cystoscope—a thin tube with video camera that is inserted into the bladder), and biopsy results of suspicious areas. Biopsies in the former area of CIS were required even if the appearance was normal. In Phase 1, patients without progressive disease were allowed to electively continue study drug after the 3-month visit. In total, 22 patients were dosed with the study drug and evaluable for efficacy at the 3-month visit. One patient included in evaluations for safety evaluation was excluded from efficacy.

Overall, across all doses, patients dosed with detalimogene achieved a CR, corresponding to a CR rate at any time of 73%. At the 3-month timepoint, this CR rate was 68%, with 82% of patients continuing to receive additional doses of the study drug beyond 3 months. The 6-month CR rate across all doses was 45%. Within the dose selected for the pivotal portion of the study, the CR rates at 3 and 6 months were 70% and 60%, respectively, with 90% of patients continuing on the study drug beyond 3 months.

Phase 2 Study Design

The Phase 2 portion of the study is open-label and is comprised of three independent single arm cohorts of patients. Cohort 1, the pivotal cohort, enrolled 125 patients with high-risk BCG-unresponsive NMIBC with CIS, with or without co-occurring papillary disease. Cohort 2 is evaluating detalimogene in high-risk, BCG-naïve NMIBC patients with CIS (Cohort 2a) or high-risk BCG-exposed NMIBC patients with CIS (Cohort 2b). Cohort 3 is evaluating detalimogene in high-risk BCG-unresponsive papillary only NMIBC patients. Although the treatment is the same for each cohort, an independent set of analysis will occur for each cohort. As of November 11, 2025, Cohorts 2a, 2b, and 3 had enrolled 30 patients, 45 patients, and 36 patients, respectively.

In Phase 2, treatment cycles are 12 weeks in duration and dosing occurs at weeks 1, 2, 5 and 6 of each 12-week cycle. Patients are administered 800µg/ml intravesically at each dosing. In addition to urine cytology and cystoscopic inspection, a bladder mapping biopsy to confirm a CR is required at the 12-month evaluation.

For all subsequent evaluation cycles beyond week 12 (e.g., weeks 24, 36, 48, and beyond), the presence of any high-risk tumor in the bladder will render a patient ineligible to continue on-study. More specifically, (i) patients with no evidence of high-risk tumor will be classified as in CR, remain on-study, and enter the next 12-week course of therapy as specified in the protocol, whereas (ii) patients with biopsy-confirmed evidence of CIS, high-risk Ta, or high-risk T1 disease or greater will be classified as non-CR and will discontinue the study. Patients who remain in CR at week 48 will enter maintenance treatment for up to four 12-week cycles through week 96. Maintenance treatment will consist of 2 detalimogene instillations per 12-week cycle, administered at week 1 and at week 2. Patients in CR at the end of the 8 cycles (week 96) can choose to continue in maintenance treatment for up to 4 more cycles (through week 144) or enter a follow-up period for quarterly visits (every 12 weeks) through week 144 or until non-response.

Phase 2 Study Endpoints

In the second half of 2025, following discussions with FDA, the Company announced the primary endpoint for Cohort 1 will change to percentage of patients with CR at any time, based on cystoscopic exam, urine cytology, and biopsies, from its previous primary endpoint of landmark CR rate at 48 weeks. This updated primary endpoint is consistent with recently approved products for BCG-unresponsive NMIBC registered with FDA. Key secondary endpoints include duration of response of the responding patients and percentage of patients with duration of response ≥1 year, CR rates at landmark timepoints, progression-free survival, and cystectomy-free survival.

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Phase 2 Study: Preliminary Efficacy

On September 26, 2024, we shared preliminary data from the first 21 patients who had reached their 12-week evaluation in the ongoing pivotal cohort of the LEGEND study, including 17 patients who were also assessed at six months. The CR rate at any time was 71%, the CR rate at three months was 67% and the CR rate at six months was 47% (Kaplan Meier estimate of 51%). The data cut-off date was September 13, 2024.

Phase 2 Study: Preliminary Safety

Detalimogene’s overall tolerability profile as presented in September 2024 was favorable, and there were no drug-related discontinuations in the study as of this date. Of the 42 patients assessed for safety, inclusive of all Phase 2 cohorts, 48% experienced at least one treatment-related adverse event (TRAE), which were mainly Grade 1/2 in severity. The most common TRAEs were dysuria (21.4%), bladder spasm (19%), pollakiuria (11.9%) and fatigue (11.9%). There were no Grade 4 or Grade 5 TRAEs reported.

Phase 2 Study: Protocol Amendment

In conjunction with the preliminary data presented on September 26, 2024, we announced an important amendment to the LEGEND Phase 2 protocol that, among other changes, modified how patients are evaluated and treated at key points during the trial. The amended LEGEND protocol stipulates that patients who present with CIS plus T1 disease at screening must undergo an initial TURBT to remove the T1 lesion, followed by a secondary resection at the lesion site. Should residual T1 disease be present following the second resection, the patient is ineligible to enter the LEGEND trial. Regarding patient assessment at the end of the first 12-week cycle, patients will be evaluated as follows: (i) patients with no evidence of high-risk tumor will be classified as being in CR, will remain on-study, and will enter the next 12-week course of therapy; (ii) patients with disease that has not responded to therapy but not progressed in stage will be classified as not in CR, will have any papillary lesions resected via TURBT, will remain on-study, and will enter the next 12-week course of therapy; and (iii) patients with disease that has progressed in stage will be required to come off-study. If a patient is suspected of having persistent or recurrent disease at 6 months, or recurrent disease at 9 months, biopsy confirmation is required to remove a patient from the study.

Phase 2 Study: Updated Preliminary Efficacy

On November 11, 2025, the Company announced updated preliminary efficacy data from two patient subpopulations of the intent-to-treat ("ITT”) patient population of Cohort 1, which the Company defines as of (i) patients who received at least one dose of detalimogene and had at least one post-baseline disease assessment and were enrolled prior to the amendment of the protocol in the fourth quarter of 2024 (the "Pre-Protocol Amendment Patients”) and (ii) patients who received at least one dose of detalimogene and had at least one post-baseline disease assessment and were enrolled following the amendment of the protocol in the fourth quarter of 2024 (the "Post-Protocol Amendment Patients”). As of October 24, 2025, the ITT population consisted of 31 Pre-Protocol Amendment Patients and 62 Post-Protocol Amendment Patients. An additional 10 patients who were enrolled prior to the protocol amendment in the fourth quarter of 2024 were included in the updated data for the Pre-Protocol Amendment Patient subpopulation. The table below summarizes preliminary efficacy results from the two separate patient subpopulations:

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Data as of October 24, 2025.

* ITT: Intent-To-Treat population includes all Pre-Protocol Amendment Patients and Post-Protocol Amendment Patients, respectively, who received at least 1 dose of treatment and had at least 1 post-baseline disease assessment.

** CR rates at 6 months include only patients who were evaluable at the 6-month timepoint or had disease progression prior to the 6-month assessment.

CI: 95% Confidence Interval

The preliminary efficacy data for Pre-Protocol Amendment Patients demonstrated a markedly lower 12-month CR rate than those of FDA-approved products for BCG-unresponsive NMIBC patients.

Among the Post-Protocol Amendment Patients, four patients that did not have a CR at the 3-month assessment converted to a CR at the 6-month assessment. In addition, of the 23 patients in this subpopulation that had a CR at the 6-month assessment, five patients remained in CR at the 9-month assessment, 17 patients were pending their 9-month assessment and one patient dropped out of the study prior to the 9-month assessment.

Phase 2 Study: Preliminary Safety Update

Detalimogene’s overall tolerability profile was favorable. Of the 125 patients assessed for safety in Cohort 1, as of October 24, 2025, 42% experienced at least one TRAE, which were mainly Grade 1/2 in severity, except for three patients (2.4%) that experienced Grade 3 TRAEs. The following table contains an overview of this preliminary safety data:

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* 2 patients experienced urinary tract infection, 1 experienced pyelonephritis.

Data as of October 24, 2025; Data collection and cleaning is ongoing, TRAE = Treatment-Related Adverse Event.

Detalimogene voraplasmid: Design and Mechanism of Action

Detalimogene contains a non-integrative plasmid DNA (pDNA) packaged in our proprietary DDX delivery platform that is further combined with the excipient polyethylene glycol-b-poly-L-glutamic acid (PEG-b-PLE), a di-block co-polymer

The pDNA component of detalimogene encodes the two linked subunits (p40 and p35) of the human (h) IL-12 cytokine. Also encoded within the same plasmid are two RNA products (adenoviral VA RNA1 (VA1) and eRNA11a; annotated together as eRNA41H) that coordinate to activate RIG-I. The dsRNA directly agonizes the intracellular protein RIG-I, while VA1 is an inhibitor of adenosine deaminase acting on RNA (ADAR), an RNA editing enzyme, and the double-stranded RNA-dependent protein kinase (PKR), a protein translation inhibitor. Together, VA1 and eRNA11a synergistically boost RIG-I activity.

Analysis of intravesical mEG-70 treatment in an orthotopic bladder cancer model

To evaluate the therapeutic benefit of detalimogene preclinically, an orthotopic model of murine bladder cancer was established by implanting syngeneic MB49 urothelial carcinoma cells that stably express luciferase (MB49luc) into murine bladders. Baseline tumor burden was confirmed by bioluminescence using in vivo imaging before two weekly IVI of mEG-70, a murine-reactive surrogate for detalimogene voraplasmid, with the study design captured in the top panel of the figure below. mEG-70 mediated a dose-dependent reduction of pre-existing tumor burden as evidenced by diminished bioluminescent signal on Day 29 of the study. Note in the figure below, the right panel displays individual animals, with the color scale indicating the intensity of the tumor signal, from blue (lowest) to red (highest), and areas without color indicating a lack of tumor. The graph on the left displays the geometric mean across all animals, ± 95% confidence interval.

We further examined the durability of the anti-tumor response by monitoring long-term survival until all mice succumbed to bladder cancer or were deemed cured, which was defined as no evidence of bioluminescent signal with no clinical signs of bladder cancer, including palpable bladder mass and hematuria. Over 90% of mice treated with mEG-70 had durable anti-tumor responses as demonstrated by long-term disease-free survival with no disease relapse during the 100-day monitoring period. In contrast, about 90% of sham-treated animals had succumbed to disease during the same period. We believe these data demonstrate the rapid, robust, and durable anti-tumor effects of mEG-70 in the orthotopic model of bladder cancer.

Long-term effects, immunological memory, and systemic immunity mediated by mEG-70

We believe that the long-term survival benefit and lack of relapse in mEG-70-treated animals suggested that immunological memory may have been established. To further explore this, we examined protective immunity against tumor re-challenge, wherein mEG-70-treated mice with complete disease regression and no relapse (‘mEG-70-cured’) were re-challenged orthotopically with MB49luc cells to assess protection from recurring disease. All mEG-70-cured mice were resistant to tumor recurrence, as shown by negative bioluminescence signal up to 3 weeks after re-challenge. In contrast, indicative of tumor burden, all age-matched naïve controls had positive bioluminescence signal following cell implantation (figure below; bottom panel displays luminescence from each individual animal reflecting tumor burden from luciferase expression with the color scale indicating the intensity of the tumor signal, from blue

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(lowest) to red (highest), and areas without color indicating a lack of tumor; top panel reflects geometric means ± 95% confidence interval).

As shown in the figure below, to determine if local treatment to the bladder results in systemic anti-tumor immunity, mice cured of orthotopic bladder cancer by mEG-70 were challenged with MB49luc cells subcutaneously on the flank and tumor growth was monitored. Although age-matched naïve controls showed rapid tumor growth, all mEG-70-cured mice remained tumor free up to 50 days post-rechallenge. To investigate whether the abscopal anti-tumor immunity was specific to MB49luc cells, a separate cohort of mice was re-challenged with antigenically distinct melanoma tumor cells (B16-F10). Although mEG-70-cured mice were resistant to re-challenge with MB49luc cells, the B16-F10 tumors grew on the mouse flank, suggesting that long-term anti-tumor effect is antigen-driven and specific to the primary tumor.

Other Bladder Cancer Indications

Our preclinical data package utilizes the MB49 cancer cell line, which, when instilled into the bladder of a mouse, can generate tumors reflective of muscle invasive bladder cancer. We believe that the preclinical data we have gathered using this murine model system, especially the data suggesting mEG-70 drives a potent immune memory effect that renders the host resistant to tumor re-challenge, could potentially support the use of detalimogene in other forms of bladder cancer, such as muscle invasive disease, as well as other forms of NMIBC such as intermediate-risk disease.

Commercialization Strategy

In accordance with our clinical development plan, we are planning to file a BLA for detalimogene for the treatment of NMIBC patients who are BCG-unresponsive with CIS in the second half of 2026 based on the expected Phase 2 results from the pivotal cohort of the LEGEND study, if the results support filing. If the FDA grants us marketing approval for detalimogene in the United States, we currently plan to commercialize detalimogene in the United States ourselves. Our current plan is to establish a U.S.-focused sales and marketing organization to coordinate with high-prescribing community urology centers in the United States. As part of our commercialization strategy, our plan is to also establish a specialty urologic medical science liaison team to support scientific exchange

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with and education of physicians and scientists about detalimogene. To proactively support these efforts, we will seek to continue expanding our relationships with key opinion leaders as well as our trial investigators while expanding physician and patient education about the potential benefits of detalimogene versus alternative therapies. We have not yet determined our commercialization strategy outside of the United States.

Manufacture and Supply

Detalimogene voraplasmid is a nanoparticle suspension containing the plasmid deoxyribonucleic acid (pDNA) drug substance encapsulated in a proprietary polymer, DDX, and further combined with a custom-manufactured methoxy-poly(ethylene glycol)-block-poly(L-glutamic acid) diblock co-polymer (abbreviated as PEG-b-PLE). DDX and PEG-b-PLE are novel excipients. The drug product is formulated as an aqueous nanoparticle dispersion, filter sterilized, lyophilized to a dry powder, and stored at -20°C.

We do not currently own or operate any manufacturing facilities for the clinical or commercial production of drug product.

We have leveraged our internal expertise and know-how to develop and scale up the manufacturing processes for our proprietary DDX and drug product before transferring them to qualified external contract manufacturers or contract manufacturing organizations (“CMO”). Additionally, we are conducting studies to understand and establish controls for all critical process parameters and critical quality attributes for our drug product. The PEG-b-PLE excipient and pDNA drug substance are custom manufactured and purchased from qualified cGMP manufacturers located in the European Union. All critical excipients, drug substance and drug product are currently manufactured at cGMP-compliant CMOs at a scale that we believe can meet our needs for a commercial launch of detalimogene for the BCG-unresponsive NIMBC indication in the United States if approved by the FDA.

We believe that our manufacturing processes are robust, cost-effective and scalable. These manufacturing processes are patent-protected and involve significant proprietary know-how. We also have a global, royalty-bearing, non-exclusive license to use certain patents and know-how relating to a proprietary plasmid DNA backbone for high-yield production and efficient expression of transgene in target tissues. Our manufacturing process is in accordance with current Good Manufacturing Practice (cGMP) and quality system regulations for drugs and biologics.

We currently rely on our commercial relationships with independent CMOs to supply our clinical trials. We have performed detailed quality audits in the past and will continue to conduct periodic quality audits of their facilities per existing quality agreements. We believe that our suppliers will be capable of providing sufficient quantities of each component to meet our clinical trial supply needs, as well as our commercial launch within the United States if and when approved by the FDA. We have supply agreements in place with multiple CMOs to support manufacturing, release testing, stability analysis, clinical labeling and packaging of detalimogene for the Phase 2 portion of the LEGEND study. We plan to enter into long term commercial supply agreements with selected qualified CMOs to supply detalimogene in the event that we are granted marketing approval in the United States. Other CMOs may be used in the future for commercial manufacturing.

Intellectual Property

Our commercial success depends in part on our ability to protect, obtain, enforce and maintain exclusivity around our gene delivery technology and product candidates through intellectual property protection, as well as our ability to operate without infringing, misappropriating or otherwise violating the proprietary rights of others and to prevent others from infringing, misappropriating or otherwise violating our proprietary rights.

We strive to protect, maintain, enforce and enhance the proprietary technology, inventions and improvements that are commercially material to our business, including by seeking, maintaining and defending our patent rights. We have and are expecting to maintain granted patents, and we continue to file and prosecute patent applications directed to our modified oligomeric chitosan-based nanoparticle gene delivery technology independently or in combination with therapeutic genes in an effort to establish intellectual property positions relating to new compositions of matter and novel treatments of various indications.

We also rely, in part, on trade secrets and know-how to maintain exclusivity to our technology. We strive to protect our proprietary information that is not covered by registered intellectual property instruments by entering into confidentiality and invention assignment agreements with employees, collaborators and consultants. While protecting trade secrets and know-how presents challenges due to, for example, movement of personnel and the natural evolution of the knowledge in the field of our technology over time, we strive to actively manage exchanges of information with third parties to minimize the risks of dissemination.

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Patent Portfolio

Our patent portfolio includes composition of matter, method of treatment and manufacturing process protection for our lead product candidate detalimogene. We have taken a multi-tiered approach to our patent strategy, and in doing so we have captured a series of sequential technical developments leading to and incorporated within detalimogene.

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First, as of October 31, 2025, we own two patent families comprising seven granted U.S. patents, two pending U.S. non-provisional applications, and 85 corresponding granted foreign patents and pending foreign patent applications in jurisdictions including Australia, Brazil, Canada, China, Eurasian Patent Organization, the European Patent Office, Austria, Belgium, Switzerland, Czech Republic, Germany, Denmark, Estonia, Spain, Finland, France, United Kingdom, Greece, Hong Kong, Hungary, Ireland, Italy, Luxembourg, Latvia, Macedonia, Netherlands, Norway, Poland, Portugal, Sweden, Slovenia, Slovakia, Turkey, Israel, India, Japan, Philippines, Republic of Korea, Mexico, New Zealand, Singapore and South Africa with claims directed to the dual-derivatization scheme that constitutes the core of our DDX-based gene delivery platform, including granted and pending composition of matter claims relating to the nature of the hydrophilic polyol used in the dual derivatization scheme, as well as methods of use and treatment. The U.S. and foreign patents directed to this subject matter will expire between 2033 and 2034, absent any applicable patent term extension or patent term adjustment.

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Second, as of October 31, 2025, we own one patent family comprising one U.S. non-provisional application and 15 corresponding granted foreign patents and pending foreign patent applications pending in jurisdictions including Australia, Brazil, Canada, China, the European Patent Office, Hong Kong, Israel, India, Japan, Republic of Korea, Mexico, New Zealand, Philippines, Singapore and South Africa with claims directed to the non-covalent, reversible coating of our nanoparticle technology for enhanced delivery, which enhances transfection and gene expression in detalimogene. The pending claims include compositions of matter and methods of use, and the patents issuing from this patent family will expire in 2040, absent any applicable patent term extension or patent term adjustment.

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Third, as of October 31, 2025, we own one patent family comprising one U.S. non-provisional application and 15 corresponding foreign patent applications pending in jurisdictions including Australia, Brazil, Canada, China, the European Patent Office, Hong Kong, Israel, India, Japan, Republic of Korea, Mexico, New Zealand, Philippines, Singapore and South Africa with claims directed to the unique combination of immunological cargos, IL-12 and RIG-1 agonists, that are delivered in detalimogene, including composition of matter claims relating to alternatives to our RIG-I agonists, as well as methods of using same in the treatment of mucosal cancers. The patents issuing from this patent family, if any, will also expire in 2040, absent any applicable patent term extension or patent term adjustment.

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Fourth, as of October 31, 2025, we own one patent family comprising one granted U.S. patent, one pending U.S. non-provisional application, and six corresponding granted foreign patents and pending foreign patent applications in jurisdictions including Australia, Canada, China, the European Patent Office, Israel and Japan with claims directed to the use of our chitosan-based nanoparticle gene delivery technology in the treatment of various inflammatory gut disorders. The patents issuing from this patent family will expire in 2037, absent any applicable patent term extension or patent term adjustment. In this patent family, U.S. Patent No. 11,603,398 received a patent term adjustment of 154 days thereby extending the expiry date to at least April 12, 2038.

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Fifth, as of October 31, 2025, we own one patent family comprising one U.S. non-provisional application and four corresponding foreign patent applications pending in jurisdictions including Australia, Canada, the European Patent Office and Hong Kong with claims directed to the use of our chitosan-based nanoparticle gene delivery technology in the treatment of various lung disorders. The patents issuing from this patent family, if any, will expire in 2041, absent any applicable patent term extension or patent term adjustment.

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Sixth, as of October 31, 2025, we own one patent family comprising one U.S. non-provisional application and 15 corresponding foreign patent applications pending in jurisdictions including Australia, Brazil, Canada, China, the European Patent Office, Hong Kong, Israel, India, Japan, Republic of Korea, Mexico, New Zealand, Philippines, Singapore and South Africa with claims directed to the use of detalimogene in the treatment of various metastatic cancers, based on data obtained in one of the cancer models. The patents issuing from this patent family, if any, will expire in 2042, absent any applicable patent term extension or patent term adjustment.

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Seventh, as of October 31, 2025, we own one patent family comprising two granted U.S. patents and corresponding granted foreign patents in jurisdictions including Australia, the European Patent Office, Belgium, Switzerland, Germany, France, United Kingdom, Ireland, Liechtenstein, Netherlands, Hong Kong, and New Zealand with claims directed to the use of low molecular weight chitosan in oral gene delivery, including composition of matter and method of use claims. The US and foreign patents directed to this subject matter will generally expire in 2027, absent any applicable patent term extension or patent term adjustment. In this patent family, U.S. Patent No. 8,846,102 received a patent term adjustment of 1737 days thereby extending the expiry date to at least December 31, 2031, and U.S. Patent No. 9,404,088 received a patent term adjustment of 736 days thereby extending the expiry date to at least April 4, 2029.

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Eighth, as of October 31, 2025, we own one patent family comprising three granted U.S. patents and 28 corresponding granted foreign patents in jurisdictions including Australia, Canada, China, the European Patent Office, Austria, Belgium, Switzerland, Germany, Denmark, Spain, Finland, France, United Kingdom, Ireland, Iceland, Italy, Netherlands, Norway, Poland, Portugal, Sweden, Slovenia, Hong Kong, Israel, Japan, Republic of Korea, Mexico, India and Singapore with claims

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directed to certain methods of manufacturing our nanoparticles, including composition of matter, methods of making, and product-by-process claims. The US and foreign patents directed to this subject matter will expire in 2028, absent any applicable patent term extension or patent term adjustment. In this patent family, U.S. Patent No. 8,722,646 received a patent term adjustment of 327 days thereby extending the expiry date to at least August 19, 2029.

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Ninth, as of October 31, 2025, we have one pending PCT application directed to the optimized clinical treatment protocol for detalimogene in the treatment of bladder cancer, based on the LEGEND study (NCT04752722). The patents issuing from this patent family, if any, will expire in 2044, absent any applicable patent term extension or patent term adjustment.

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Tenth, as of October 31, 2025, we have one pending U.S. provisional application directed to improved compositions and methods for expressing genetic medicines in the bladder. The patents issuing from this patent family, if any, will expire in 2046, absent any applicable patent term extension or patent term adjustment.

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Finally, as of October 31, 2025, we have one pending U.S. provisional application directed to the treatment of bladder cancer with immunomodulatory antibodies. The patents issuing from this patent family, if any, will expire in 2046, absent any applicable patent term extension or patent term adjustment.

The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the date of filing of the first non-provisional patent application to which priority is claimed. In the United States, patent term may be lengthened by patent term adjustment, which compensates a patentee for administrative delays by the USPTO in granting a patent or may be shortened if a patent is terminally disclaimed over an earlier-filed patent. In the United States, the term of a patent that covers an FDA-approved drug may also be eligible for a patent term extension of up to five years beyond the expiration of the patent under the Hatch-Waxman Act, which is designed to compensate for the patent term lost during the FDA regulatory review process. The length of the patent term extension involves a complex calculation based on the length of time it takes for regulatory review. A patent term extension under the Hatch-Waxman Act cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval and only one patent applicable to an approved drug may be extended. Moreover, a patent can only be extended once, and thus, if a single patent is applicable to multiple products, it can only be extended based on one product. Similar provisions are available in Europe and certain other foreign jurisdictions to extend the term of a patent that covers an approved drug. There is no guarantee that the applicable authorities will agree with our assessment of whether any extensions should be granted, and if granted, the length of these extensions.

Our general filing strategy regarding registrable intellectual property is to seek patent protection in major markets. For example, our core DDX-based gene delivery technology is protected by issued patents in the United States, Europe (with country coverage within Europe), Japan, China, Hong Kong, India, Eurasia, South Korea, Canada, Australia, New Zealand, Brazil, Mexico and several other jurisdictions. Our filing strategy typically involves the filing of an international PCT patent application followed by national filings in specific countries. The selection of countries is made on a case-by-case basis.

Our patent portfolio currently comprises eleven patent families, which include approximately 135 issued patents and 64 pending patent applications, including 13 issued U.S. patents, four issued European patents (with country coverage within Europe), seven non-provisional pending U.S. applications, six European pending applications, one pending PCT application, and two pending U.S. provisional applications. enGene exclusively owns all eleven patent families in its patent portfolio.

The patent positions of companies like us are generally uncertain and involve complex legal, scientific, and factual questions. Changes in the patent laws and rules, either by legislation, judicial decisions, or regulatory interpretation in other countries may diminish our ability to protect our inventions and enforce our intellectual property rights, and more generally could affect the value of our intellectual property. In particular, our ability to stop third parties from making, using, selling, offering to sell, importing or otherwise commercializing any of our patented inventions, either directly or indirectly, will depend in part on our success in obtaining, defending and enforcing patent claims that cover our technology, inventions, and improvements. In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Consequently, we do not know whether any of our product candidates will be protectable or remain protected by enforceable patents or will be commercially useful in protecting our commercial products and methods of using and manufacturing the same. We also cannot predict whether the patent applications we are currently pursuing will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient proprietary protection from competitors. Any patents that we hold or control may be challenged, circumvented or invalidated by third parties. In addition, our agreements and security measures protecting our trade secrets and know-how may be breached, and we may not have adequate remedies for any such breach. Further, our trade secrets may otherwise become known or independently discovered by competitors.

See “Risk Factors—Risks Related to Our Intellectual Property” for important information about risk related to our intellectual property.

Strategic License Agreement

On April 10, 2020, we entered into a non-exclusive license agreement (the “License Agreement”) with Nature Technology Corporation (“NTC”) pursuant to which NTC granted enGene a worldwide non-exclusive, royalty-bearing and sublicensable license to

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certain patents and know-how relating to the NanoplasmidTM vector backbone that is used in detalimogene voraplasmid to research, develop, make, use, import, sell and offer to sell, any gene and cell therapy products incorporating the NanoplasmidTM vector backbone (excluding any such products in the field of dermatology). The licensed intellectual property includes 10 patent families (inclusive of all related divisional, continuation, continuation-in part, substitutes, counterparts and/or any foreign equivalents filed in any country within such family) and certain know-how. NTC is solely responsible for the preparation, filing, prosecution, cost and maintenance of all patent applications and patents included in the licensed intellectual property.

Unless terminated earlier, the License Agreement will continue until no valid claim of any licensed patent exists in any country. NTC may terminate the License Agreement if we fail to make any payments within a specified period after receiving written notice of such failure. Either party may terminate the License Agreement in the event either party commits a material breach and fails to cure such breach within a certain period. We can terminate the License Agreement for convenience with prior notice to NTC.

Under the License Agreement, we are obligated to make annual payments of $50 thousand until the first sale of a product for which a royalty is due and make a payment to NTC of $50 thousand upon assigning the License Agreement to a third-party. We are also required to make a one-time payment of $50 thousand for the first dose of a product covered by a valid claim of a licensed patent (a “Milestone Product”) in the first patient in a Phase 1 clinical trial or, if there is no Phase 1 clinical trial, in a Phase 2 clinical trial, as well as a one-time payment of $450 thousand upon regulatory approval of a Milestone Product by the FDA. The first milestone related to the first dose of a Milestone Product was achieved during the year ended October 31, 2021. The second milestone, regulatory approval of a Milestone Product, has not been achieved as of the year ended October 31, 2025. We are also required to pay NTC a royalty percentage in the low single digits of the aggregate net product sales in a calendar year by us, our affiliates or sublicensees on a product-by-product and country-by-country basis, as long as the composition or use of the applicable product is covered by a valid claim in the country where the net sales occurred. Royalty obligations under the License Agreement will continue until the expiration of the last valid claim of a licensed patent covering such licensed product in such country. In the event that we or any of our affiliates or sublicensees manufacture any GMP lot of a licensed product, then we or any such affiliate or sublicensee will be obligated to pay NTC an amount per manufactured gram of GMP (or its equivalent) lot of product, which varies based on the volume manufactured. Such manufacturing payment will expire on a product-by-product basis upon receipt of regulatory approval to market a product in any country in the licensed territory. Under the License Agreement, enGene is permitted to sublicense our rights to third parties and we are not required to share any of the license revenue with NTC.

NTC was acquired by Aldevron, LLC in January 2022. The terms of the existing License Agreement described above remained the same. See "Notes to the Financial Statements - Note 7, License Agreement and Clinical Research Organization" for additional information about the License Agreement.

Competition

The biotechnology and pharmaceutical industries are characterized by rapid innovation of new technologies, fierce competition, and strong defense of intellectual property. While we believe that detalimogene and our knowledge, experience and scientific resources provide us with competitive advantages, we may face competition from pharmaceutical and biotechnology companies, academic institutions, governmental agencies and public and private research institutions, among other things.

Many of our competitors, either independently or with strategic partners, have substantially greater financial, technical and human resources than we do. Accordingly, our competitors may be more successful than we are in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approval for treatments and achieving widespread market acceptance. Merger and acquisition activity in the biotechnology and biopharmaceutical industries may result in resources being concentrated among a smaller number of our competitors. These companies also compete with us in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites and patient registration for clinical trials and acquiring technologies complementary to, or necessary for, our programs. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

Our commercial opportunity could be substantially limited if our competitors develop and commercialize products that are more effective, safer, less toxic, more convenient or less expensive than products we may develop. In geographic locations that are critical to our commercial success, competitors may also obtain regulatory approvals before us, resulting in our competitors building a strong market position in advance of the entry of our products. In addition, our ability to compete may be affected in many cases by insurers or other third-party payers seeking to encourage the use of other drugs. The key competitive factors affecting the success of any products we may develop are likely to be their efficacy, safety, convenience, price and availability of reimbursement.

There are five FDA-approved products for the treatment of high risk NMIBC patients that are unresponsive to BCG, and multiple companies have therapies in clinical development for such treatment. While many of these products are neither intravesical nor monotherapy, they may nonetheless compete with us for patient recruitment in clinical trials as well as for commercial sales, if detalimogene is approved. Furthermore, to the extent Merck & Co. (“Merck”) or another manufacturer increases the supply of BCG, there may be less demand for alternative treatments such as detalimogene in BCG-naïve or BCG-exposed patients. In addition, there are numerous companies that have commercialized or are developing treatments for NMIBC, including Aura Biosciences, Inc.,

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AstraZeneca, Bristol Meyers Squibb, CG Oncology Inc., Hoffman-La Roche AG (Roche), ImmunityBio Inc., Johnson & Johnson Inc., Merck, Protara Therapeutics, Inc., Pfizer, Inc., and UroGen Pharma, Inc.

Competing products include, among other things, the following FDA-approved products:

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Adstiladrin® (nadofaragene firadenovec), a non-replicating adenoviral vector-based genetic medicine that is manufactured and marketed by Ferring Pharmaceuticals A/S.

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Keytruda® (pembrolizumab), a Merck product, for the treatment of patients with high-risk BCG-unresponsive NMIBC with CIS with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy.

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VALSTAR® (valrubicin), marketed by Endo Pharmaceuticals, an anthracycline topoisomerase inhibitor for intravesical treatment of BCG-refractory CIS of the urinary bladder in patients for whom immediate cystectomy would be associated with unacceptable morbidity or mortality.

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Anktiva® (nogapendekin alfa inbakicept-pmln), marketed by ImmunityBio, an engineered IL-15 superagonist protein complex that is approved for use in patients with BCG-unresponsive NMIBC with CIS, with or without papillary tumors, when administered in combination with BCG.

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Inlexzo™ (gemcitabine intravesical system), marketed by Johnson & Johnson, intravesical drug-releasing system that is placed into the bladder and slowly releases gemcitabine, a chemotherapeutic agent, that is approved for use in patients with BCG-unresponsive NMIBC with CIS, with or without papillary tumors.

See “Risk Factors — Risks Related to Our Business — We face significant competition from other biotechnology and pharmaceutical companies, which may result in our competitors discovering, developing or commercializing products before us or more successfully than we do. Our business and results of operations could be adversely affected if we fail to compete effectively” for important information about risks respecting competition.

Regulatory Matters

The development, production, testing, distribution, and marketing of biologics like the ones we are developing are subject to strict regulations by various U.S. federal, state, and local agencies in addition to foreign regulatory authorities. These regulations cover a wide range of aspects, including research, safety, efficacy, labeling, packaging, storage, distribution, and advertising, as well as post-approval monitoring and reporting. Our Company, as well as our vendors, partners, contract research organizations (CROs), and manufacturers, will need to comply with these regulations. To gain approval for our product candidate, we need to comply with the regulatory requirements of various governing agencies, including those related to preclinical and clinical trials, manufacturing, and commercialization. This process requires a significant investment of time and financial resources. In the United States, our focus market, the FDA regulates biologics under the Federal Food, Drug, and Cosmetic Act and the Public Health Service Act, and other federal, state, and local regulations also apply. Our lead product candidate, detalimogene, is not yet approved for marketing in the United States.

See “Risk Factors — Regulatory Risks” for important information about risks respecting regulatory matters.

To obtain approval for our product candidates for therapeutic use in the United States, we must follow a series of steps regulated by the FDA. This includes conducting preclinical studies in compliance with regulations, meetings with the FDA, submitting an investigational new drug application, or “IND,” to the FDA, obtaining institutional review board, or “IRB,” or ethics committee approval at each clinical trial site, conducting clinical trials in compliance with Good Clinical Practice (“GCP”) requirements, preparing and submitting a BLA accompanied by fees, undergoing FDA pre-approval inspections of manufacturing facilities, and having potential FDA audits of the clinical trial sites. Finally, the FDA will review and approve the BLA and provide any recommendations before the biologic drug can be sold commercially in the United States.

Preclinical and clinical testing of biological drug products

In order to test a drug or biologic in humans, it must first undergo extensive preclinical testing, which includes laboratory evaluations and animal studies to determine safety and efficacy. These studies must comply with federal and state regulations, including Good Laboratory Practices (“GLP”) requirements for safety and toxicology studies. The results of these studies, as well as manufacturing and analytical data, must be submitted to the FDA as part of an IND. The IND is a request for authorization to administer the product to humans and must be approved before clinical trials can begin. The IND submission focuses on the protocol for the initial clinical study and includes results of animal and in vitro studies, as well as any available human data to support the use of the investigational product. The IND becomes effective 30 days after receipt by the FDA, unless the FDA raises concerns or questions about the study, in which case a clinical hold is imposed until the concerns are resolved.

During the clinical stage of development, the product candidate is administered to patients or healthy volunteers under the supervision of qualified investigators in accordance with GCP requirements. Each clinical trial must be reviewed and approved by an IRB to ensure that the risks to individuals participating in the clinical trial are minimized and reasonable in relation to the anticipated benefits. The FDA, IRB, or sponsor may suspend or discontinue a clinical trial at any time on various grounds. Some studies also include

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oversight by a data safety monitoring board. Clinical trials must be reported to public registries within specific timeframes. While international clinical trials can be conducted under an IND, the FDA does not require that all foreign clinical trials be conducted under United States INDs. The FDA will accept a well-designed and conducted foreign clinical study not conducted under an IND if the study was conducted in accordance with GCP requirements and the FDA is able to validate the data through an onsite inspection if necessary.

Clinical trials that are carried out to determine the safety and efficacy of a drug for the purpose of obtaining marketing approval through a BLA are typically carried out in three phases that can occur simultaneously, in combination, or staggered.

Phase 1: Phase 1 of clinical trials involves administering the investigational product to healthy human volunteers or patients with the target disease or condition for the first time. The primary objective of these studies is to evaluate the safety, dosage tolerance, absorption, metabolism and distribution of the investigational product in humans, identify any side effects associated with increasing doses, and potentially gather preliminary evidence of effectiveness.

Phase 2: Phase 2 clinical trials usually involve giving the investigational product to a small group of patients with a particular disease or condition to assess its effectiveness, determine the best dosage and dosing schedule, and detect any potential risks or side effects. To gather data before conducting more extensive and costly Phase 3 trials, several Phase 2 studies may be conducted.

Phase 3: Phase 3 trials usually involve testing the investigational product in a larger group of patients to confirm its efficacy and safety. The trials are conducted at multiple locations and aim to establish the overall risk-benefit profile of the product. Typically, the FDA requires two well-controlled Phase 3 clinical trials to approve a BLA.

After marketing approval, Phase 4 clinical trials, also known as post-approval trials, may be conducted to gain more experience with the product in its intended use and to gather additional safety or efficacy data. The FDA may require these trials as a condition of approval. The results of clinical trials and safety reports for serious adverse events must be submitted to the FDA annually and within 15 days of the sponsor’s determination. Fatal or life-threatening adverse reactions must be reported within seven days. Along with clinical trials, companies must complete additional animal studies, develop information about the product’s biological characteristics, and establish a commercial manufacturing process that adheres to cGMP requirements. The manufacturing process must consistently produce quality batches of the product, and appropriate packaging and storage conditions must be identified through stability studies.

Expanded Access

Expanded access, also known as “compassionate use,” refers to the use of investigational products outside of their intended clinical development to treat patients suffering from serious or life-threatening diseases or conditions when no satisfactory alternative treatment options are available. FDA regulations permit access to investigational products through an IND by the treating physician or the company for treatment purposes, including individual patients, intermediate-size patient populations, and larger populations for use under a treatment protocol or treatment IND application. It is important to note that companies are not obligated to provide expanded access to their investigational products.

BLA Submission and marketing authorization by the FDA

We plan to apply for either data exclusivity or market exclusivity for our product candidates. If the necessary clinical testing is completed successfully, we will submit the results of preclinical studies and clinical trials, as well as detailed information on the product’s manufacturing, labeling, and other aspects, to the FDA in the form of a BLA. This application seeks approval to market a new biologic for one or more specific indications. The BLA must contain all relevant data from both positive and negative studies. The BLA should incorporate all important information accessible from relevant preclinical and clinical examinations, including negative or questionable outcomes as well as certain discoveries, along with itemized data on the product candidate’s science, chemistry, manufacturing and controls, and proposed naming, in addition to other things. The data submitted must be of sufficient quality and quantity to satisfy the FDA regarding the investigational product’s safety, purity, and potency in order to support marketing approval. A BLA must be approved by the FDA before a biologic can be sold in the United States.

A BLA or supplement to a BLA must also include data to assess the biological product candidate’s safety and effectiveness for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective, as required by the Pediatric Research Equity Act, or PREA. An initial Pediatric Study Plan (PSP) must be submitted within sixty days of an end-of-Phase 2 meeting or as agreed upon between the sponsor and FDA by a sponsor planning to submit a marketing application for a biological product that includes a new clinically active component, new indication, new dosage form, new dosing regimen, or new route of administration. PREA does not apply to any biological product for an indication for which an orphan designation has been granted, unless otherwise required by regulation.

In some cases, the FDA may also request additional information before deciding whether or not to accept the BLA for filing. Within 60 days of receiving a BLA, the FDA must decide whether or not to accept it for filing. This decision may include refusing to file. The FDA begins a comprehensive substantive review of the BLA as soon as the submission is accepted for filing. A BLA is reviewed by the FDA to see, among other things, if the product is safe, pure, and effective, and if the facility where it is manufactured,

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processed, packaged, or stored satisfies standards designed to guarantee the product’s continued safety, quality, and purity. Under the objectives and policies consented to by the FDA under the Prescription Drug Users Fee Act, or PDUFA, once a BLA has been submitted, the FDA’s goal for novel biological products generally is to review the application within ten months after it accepts the application for filing, or, if the application is granted priority review, six months after the FDA accepts the application for filing. The FDA does not always meet its PDUFA goal dates, and the review process may be extended. For example, the review process and the PDUFA goal date may be extended by three months if the FDA requests or if the applicant otherwise provides additional data, analysis or information that the FDA deems a major amendment.

Further, under PDUFA, as changed, each BLA should be joined by a client charge, and the patron of an endorsed BLA is likewise dependent upon a yearly program expense. FDA changes the PDUFA client expenses on a yearly premise. In some cases, fees may be reduced or waived. For example, a small business may not have to pay the application fee for the first time. In addition, unless the product also includes a non-orphan indication, there are no user fees associated with BLAs for products designated as orphan drugs. See “Orphan drug designation and exclusivity” below.

The FDA might refer an application for a biologic to any advisory committee, which is a panel of independent experts, such as clinicians and other scientific experts. It reviews, evaluates, and offers a recommendation, such as whether the biologic is sufficiently safe and effective in a particular indication for a particular population and under what conditions. While an advisory committee’s recommendations do not bind the FDA, they are carefully taken into consideration when deciding whether or not to grant marketing approval.

The FDA will typically conduct an inspection of the facility or facilities where the product is manufactured prior to approving a BLA. The FDA will not approve an application unless it finds that the manufacturing facilities and processes are adequate to guarantee consistent product production in accordance with the required specifications. Furthermore, prior to approving a BLA, the FDA might investigate at least one clinical preliminary destination to guarantee consistence with GCP and different necessities and the uprightness of the clinical information submitted to the FDA.

The FDA may require a Risk Evaluation and Mitigation Strategy (REMS) to be submitted as a condition for approving a BLA to ensure that the product’s benefits outweigh its risks. The REMS may include medication guides, communication plans, assessment plans, or other risk-minimization tools.

Once the BLA and all related information, including advisory committee recommendations and inspection reports, have been evaluated, the FDA may issue an approval letter or a Complete Response Letter. A Complete Response Letter indicates that the application is not ready for approval and lists all deficiencies found in the BLA, which need to be addressed to achieve approval. Even with additional information, the FDA may still reject the application.

If the FDA approves a product, it may impose restrictions, require additional studies, or limit approved indications for use. The FDA can also impose distribution and use restrictions or other risk management mechanisms under a REMS, which may affect the product’s market and profitability. Post-marketing studies or surveillance programs may result in the FDA limiting or preventing further marketing of the product. Changes to the approved product may also require further testing and FDA review and approval.

Expedited drug development and review programs at the FDA

The FDA has programs to speed up the development, review, and potential approval of new drugs and biologics for serious or life-threatening diseases. These programs include Regenerative Medicine Advanced Therapy (RMAT) designation, the CMC Development and Readiness Pilot (CDRP) Program, Fast Track designation, Breakthrough Therapy designation, priority review, and Accelerated Approval.

The RMAT program is intended to expedite the development and review of regenerative medicine therapies for serious or life-threatening conditions, where preliminary clinical evidence suggests potential to address unmet medical needs. This designation provides several regulatory advantages, including early and frequent engagement with the FDA, and potential for rolling review and priority review.

The FDA’s CDRP Program is designed to support accelerated development of products addressing serious conditions by providing enhanced, earlier CMC engagement during the clinical development lifecycle. The program enables sponsors to obtain timely feedback on manufacturing strategy, analytical readiness, control systems, and comparability plans to reduce CMC-related delays at the time of marketing application. Participation is limited and prioritized for products with significant potential public health impact, with the goal of ensuring CMC readiness aligns with expedited clinical and regulatory pathways.

A biologic can get Fast Track designation if it is meant to treat a serious or life-threatening disease and has the potential to address unmet medical needs for that disease. This applies to the product and the specific indication for which it is being studied. Similar to RMAT, Fast Track designation also allows sponsors to interact more with the FDA during preclinical and clinical development. There

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is also potential for rolling review, where the FDA can review parts of the BLA on a rolling basis if the sponsor provides a schedule, the FDA accepts the schedule, and the sponsor pays required fees when submitting the first section of the BLA.

There can be no assurance that detalimogene’s RMAT or Fast Track designations or participation in the CDRP program will lead to a faster development, regulatory review or approval process or increase the likelihood that detalimogene will receive marketing approval. Breakthrough Therapy designation is given to drugs that demonstrate a substantial improvement over existing therapies on clinically significant endpoints, and this designation provides intensive guidance for an efficient development program.

Products with Fast Track or Breakthrough Therapy designation may also be eligible for priority review and Accelerated Approval. Priority review is given to drugs that provide significant improvement in safety or effectiveness for serious or life-threatening diseases or conditions. Under priority review, FDA’s PDUFA goal for the review of the application is shortened to six months from the application filing date.

Accelerated Approval is given when a drug has an effect on a surrogate or early clinical endpoint that is likely to predict clinical benefit. Sponsors must agree to conduct additional post-approval studies to verify clinical benefit, and the FDA may withdraw approval if those studies fail.

While these programs may expedite the development or review process, they do not change the scientific or medical standards for approval or the quality of evidence necessary to support approval.

Post-Approval Requirements

The FDA heavily regulates drugs and biologics that are manufactured or distributed with their approval. This includes requirements related to recordkeeping, reporting, and product distribution. Companies must comply with promotion and advertising restrictions and are prohibited from marketing or promoting products for unapproved, off-label uses. Failure to comply with these requirements can result in penalties and liability under the False Claims Act (the “FCA”). Post-approval requirements may include post-market testing and surveillance to assess the product’s safety and effectiveness. Manufacturers and their subcontractors must register with the FDA and undergo periodic inspections for compliance. Changes to the manufacturing process may require FDA approval. Failure to comply can result in legal or regulatory action, and the FDA can withdraw approval if regulatory standards are not maintained. Revisions to approved labeling and other restrictions may also be imposed.

In addition, post approval, a pediatric study is typically required unless a waiver is granted. In the case of detalimogene, due to the rare incidence of bladder cancer in children, we plan to request a waiver of this requirement.

The consequences of failing to comply with FDA regulations include various restrictions such as limitations on marketing or manufacturing, product recalls, safety alerts, and mandated modifications of promotional materials and labeling. Companies may also face fines, warning letters, untitled letters, or holds on clinical trials and refusal of FDA approvals. The FDA can also take more serious actions such as product seizure or detention, injunctions, or civil or criminal penalties. In addition, companies may face consent decrees, corporate integrity agreements, debarment, or exclusion from federal healthcare programs.

Orphan drug designation and exclusivity

The Orphan Drug Act allows the FDA to give orphan drug designation (“ODD”) to drugs or biologics meant to treat rare diseases or conditions, which are defined as having a patient population of fewer than 200,000 individuals in the United States or a patient population greater than 200,000 individuals in the United States when it is not reasonable to expect that the cost of developing and making the drug available in the United States will be recovered from sales in the United States. To receive ODD, it must be requested before submitting a BLA, and the identity of the therapeutic agent and its potential orphan use are publicly disclosed after ODD is granted.

If a product receives ODD and later becomes the first FDA-approved drug for a particular clinically active component for the disease it was designated for, it is entitled to orphan drug exclusivity, meaning the FDA cannot approve any other applications, including a full BLA, to market the same biologic for the same indication for seven years from the approval of the BLA, except under specific circumstances. These circumstances include showing clinical superiority to the product with orphan drug exclusivity or if the holder of the exclusivity cannot assure the availability of sufficient quantities of the drug for patients.

Orphan drug exclusivity does not prevent the FDA from approving a different drug or biologic for the same disease or condition, or the same drug or biologic for a different disease or condition. ODD also offers benefits like tax credits for certain research and a waiver of the BLA application user fee. However, a product with ODD may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received ODD. Moreover, the exclusive marketing rights in the United States may be lost if the FDA later finds that the request for designation was materially defective or if the manufacturer can’t assure sufficient quantities of the product for patients with the rare disease or condition.

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Biosimilars and Exclusivity

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act (collectively, the “ACA”), signed into law in 2010, includes a subtitle called the Biologics Price Competition and Innovation Act (“BPCIA”), which simplified approval process for biological products that are similar to an FDA-licensed reference biological product. The FDA has issued several guidance documents outlining how to review and approve biosimilars. Biosimilarity requires that the biological product and the reference product be the same in terms of safety, purity, and potency. This can be proven through analytical studies, animal studies, and clinical studies. Interchangeability requires that a product be biosimilar to the reference product and that the biologic, and the reference biologic may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy.

An application for a biosimilar product cannot be submitted to the FDA until four years after the reference product was licensed by the FDA. Also, the approval of a biosimilar product cannot be made effective until 12 years after the reference product was licensed. During this period, another company may still market a competing version of the reference product if the FDA approves a full BLA for the competing product that shows the safety, purity, and potency of its product. The BPCIA also created exclusivity periods for biosimilars approved as interchangeable products. It is not yet clear if products deemed “interchangeable” by the FDA will be readily substituted by pharmacies, which are governed by state pharmacy law.

In the United States, a biological product may receive additional market exclusivity for six months if the manufacturer voluntarily completes a pediatric study in accordance with an FDA-issued “Written Request.” The BPCIA, which created an abbreviated approval pathway for biosimilar products, is complex and continues to be interpreted and implemented by the FDA. Recently, government proposals have sought to decrease the 12-year reference product exclusivity period. Some aspects of the BPCIA, which could affect its exclusivity provisions, have been the subject of litigation. Therefore, the impact, implementation, and regulatory interpretation of the BPCIA remain uncertain.

Regulation of combination drug products in the US

Combination products are those that are made up of different components, such as biological and device components, that are typically regulated by different FDA centers. According to FDA regulations, a combination product can be a single entity made up of two or more regulated components that are combined in some way, two or more separate products packaged together, or a product that requires the use of an approved drug, device or biological product to achieve the intended effect. The FDA assigns a lead center for review of combination products based on the product’s primary mode of action. The Office of Combination Products has been established to address issues related to combination products and provide guidance and regulations for their regulation. Combination products with a biologic primary mode of action are generally reviewed through the biologic approval process, with input from the device center to ensure the device component meets safety and performance requirements. Combination products are subject to current Good Manufacturing Practice (cGMP) regulations for drugs, biologics, and devices, including quality system regulations for medical devices. Our manufacturing process is cGMP compliant.

Other regulatory considerations for drug products

After a product candidate has been approved or commercialized, its manufacturing, sales, promotion, and other related activities are subject to regulation by various regulatory bodies in the United States. In addition to the FDA, these regulatory authorities may include the Centers for Medicare & Medicaid Services (the “CMS”), other divisions of the Department of Health and Human Services (the “HHS”), the Drug Enforcement Administration (the “DEA”), the Consumer Product Safety Commission, the Federal Trade Commission (the “FTC”), the Occupational Safety & Health Administration, the Environmental Protection Agency, as well as state and local governments and agencies.

Drug coverage and reimbursement

In the United States and many other countries, patients rely on third-party payors to cover part or all of the costs of their treatment. Having sufficient coverage and reimbursement from government healthcare programs and private insurers is critical for the success of new products. The availability of coverage and reimbursement will impact our ability to commercialize our product candidates, and the amount of reimbursement provided may not be enough for us to make a profit. Government authorities and third-party payors determine which medications they will pay for and at what level. New products may not be covered or may have limited coverage, and the reimbursement level may be lower than necessary to cover our costs. The COVID-19 pandemic has also caused uncertainty regarding insurance coverage, as many people have lost their employer-based coverage. The factors that payors consider when determining reimbursement include whether the product is covered by the plan, safe, effective, medically necessary, appropriate for the patient, and cost-effective. Discounts and rebates required by government programs and private payors may reduce the net price for drugs, and there is increasing pressure on drug companies to offer predetermined discounts. We cannot be certain that reimbursement will be available for our products or what the reimbursement level will be, and we may be subject to penalties if we do not report pricing metrics accurately and in a timely manner. We also cannot be certain that if we obtain reimbursement arrangements with payors that such arrangements will not be subject to recoupment actions or overpayment challenges, which can be time-consuming and expensive to resolve.

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Health care laws and regulations in the United States

Pharmaceutical companies must comply with various healthcare regulations enforced by the federal government and state and foreign authorities where they do business. These regulations limit financial arrangements and relationships involving the research, sale, marketing, and distribution of products authorized for sale. The laws include the federal Anti-Kickback Statute (“AKS”), which prohibits offering or receiving remuneration for referrals or purchases that may be paid under federal and state healthcare programs. The FCA and Civil Monetary Penalties Law prohibit submitting false claims for payment to the government. The federal Health Insurance Portability and Accountability Act of 1996 imposes liability for executing schemes to defraud healthcare benefit programs or falsifying information related to healthcare delivery and payment. The “Sunshine Act” requires manufacturers of reimbursable drugs, devices, biologics, and medical supplies to report physician payments and other transfers of value. The Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) imposes privacy and security obligations on certain healthcare providers, health plans, and healthcare clearinghouses. Similar state laws may apply to sales and marketing arrangements involving healthcare items or services reimbursed by non-governmental third-party payors, reporting requirements related to financial arrangements with clinicians, and state privacy and security laws governing health information can be different from HIPAA. Noncompliance with these laws can lead to significant penalties, including administrative, civil, and criminal penalties, damages, fines, disgorgement, restructuring of operations, oversight and reporting obligations, and exclusion from participation in federal and state healthcare programs.

Healthcare legislative development

Healthcare payors, whether they are government or private entities, are using more sophisticated methods to control costs, but these methods are not always suitable for new technologies like genetic medicine and treatments for rare diseases. Legislative and regulatory changes to the healthcare system in the United States and many other countries could affect our ability to sell our products profitably. The ACA, which became law in 2010, introduced a range of changes, including subjecting biologic products to competition from lower-cost biosimilars, increasing minimum Medicaid rebates, and imposing new annual fees and taxes on certain branded prescription drugs. The ACA has faced legal and political challenges. Other healthcare reform measures may also impact our business. Since the ACA was enacted, other legislative changes have been proposed and adopted in the United States, including spending reductions under the Budget Control Act of 2011 and the Right to Try Act, which provides a federal framework for certain patients to access investigational new drug products. There has also been growing interest in specialty drug pricing practices and efforts to control pharmaceutical and biological product pricing at the federal and state levels, including transparency measures and importation from other countries.

Facilities

Our corporate headquarters are located in Montreal, Canada, where we lease and occupy approximately 10,620 sq. feet of laboratory and office space at 4868 Rue Levy, Montreal, QC H4R 2P1. We also maintain office space in the United States at 99 High Street, 26th Floor, Boston, Massachusetts 02110 and 200 5th Street Waltham, Massachusetts 02451.

We believe that our current facilities are sufficient for our current needs. To meet the future needs of our business, we may lease additional or alternate space. We believe that suitable additional or substitute space at commercially reasonable terms will be available as needed to accommodate any future expansion of our operations.

Employees

As of October 31, 2025, we had 82 employees, including 81 full-time employees, 51 of whom were primarily engaged in research and development activities. Of these employees, 22 are based in Canada and 60 in the United States. None of our employees are represented by a labor organization or are party to a collective bargaining arrangement. We consider our relationship with our employees to be excellent.

Legal Proceedings

From time to time, we may be involved in legal proceedings that arise in the regular course of our business. Our management believes that we are not currently involved in any legal proceedings that are likely to have a significant negative effect on our business. However, legal proceedings can negatively affect our business, financial condition, results of operations, and future prospects, regardless of the outcome, due to costs associated with defense and/or settlement, as well as the diversion of management attention and resources, among other factors.

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