FDA selects detalimogene for manufacturing readiness program

The FDA has selected detalimogene voraplasmid (previously EG-70) as 1 of the 9 proposals chosen to participate in the Chemistry, Manufacturing, and Controls (CMC) Development and Readiness Pilot (CDRP) Program, designed to support manufacturing readiness, enGene announced in a news release.¹

Detalimogene is an investigational, non-viral gene therapy for patients with high-risk, non–muscle invasive bladder cancer (NMIBC). The agent was previously granted regenerative medicine advanced therapy (RMAT) and fast track designations from the FDA.

The CDRP program is intended to “facilitate CMC development of selected products under investigational new drug (IND) applications with expedited clinical development timeframes to help patients get access to these products sooner,” according to the FDA.² Within this program, detalimogene’s development process may benefit from increased collaboration with the FDA to scale up manufacturing capacity concurrently with ongoing clinical development.

“Manufacturing readiness in drug development is often underappreciated. We have already scaled detalimogene manufacturing to commercial-level, and CDRP is expected to help ensure CMC readiness for filing and commercialization,” said Ron Cooper, President and CEO of enGene, in the news release.¹ “Our progress on the manufacturing front is in sync with detalimogene clinical development, where we recently announced improved 6-month complete response rate in the LEGEND trial pivotal cohort.”

Data on detalimogene

Preliminary data from the phase 2 LEGEND trial (NCT04752722) were reported in November 2025.³ In total, the trial has enrolled 125 patients in its pivotal cohort, which includes patients with high-risk, BCG-unresponsive NMIBC with carcinoma in situ, with or without concomitant papillary disease. Data from this cohort are intended to support submission of a biologics license application to the FDA in the second half of 2026.

According to the company, the trial protocol was amended in the fourth quarter of 2024 to more closely align with American Urological Association guidelines and standard of care. Among all patients enrolled in the study (n = 125), 62 were enrolled under the amended trial protocol and had at least 1 post-baseline disease assessment.

Overall, data showed a 63% (95% CI, 51 to 74) complete response (CR) rate at any time point among the 62 efficacy-evaluable patients. The CR rate was 56% (95% CI, 44 to 68) at 3 months and 62% (95% CI, 46 to 76) at 6 months. All patients who completed the 9-month assessment had a CR.

The tolerability profile for detalimogene was also favorable, according to enGene. Overall, 42% of patients experienced a treatment-related adverse event (TRAEs), which were generally grade 1/2 in severity. Grade 3 TRAEs occurred in 3 patients, and no grade 4 or 5 TRAEs were reported. The most common TRAEs included bladder spasm (10.4%), dysuria (12.0%), fatigue (16.8%), micturition urgency (10.4%), and pollakiuria (10.4%).

TRAEs led to dose interruptions in 1.6% of patients and dose discontinuations in 0.8% of patients.

In addition to the pivotal cohort, the LEGEND trial is also enrolling patients with BCG-naïve NMIBC with CIS (Cohort 2a); BCG-exposed NMIBC with CIS (Cohort 2b); and BCG-unresponsive high-risk NMIBC patients with papillary-only disease (Cohort 3). Patients are being enrolled in the study across clinical trials in the US, Canada, Europe, and the Asia-Pacific region.

Preliminary completion of the study is expected in June 2026.⁴

REFERENCES

1. enGene’s detalimogene selected for FDA Manufacturing Pilot Program to support manufacturing readiness. enGene. News release. December 2, 2025. Accessed December 9, 2025. https://engene.com/engenes-detalimogene-selected-for-fda-manufacturing-pilot-program-to-support-manufacturing-readiness/

2. Chemistry, Manufacturing, and Controls Development and Readiness Pilot (CDRP) Program. US Food & Drug Administration. Accessed December 9, 2025. https://www.fda.gov/drugs/pharmaceutical-quality-resources/chemistry-manufacturing-and-controls-development-and-readiness-pilot-cdrp-program

3. Detalimogene demonstrates improved complete response rate of 62% at 6 months. News release. enGene. November 11, 2025. Accessed December 9, 2025. https://engene.com/detalimogene-demonstrates-improved-complete-response-rate-of-62-at-6-months/

4. LEGEND study: EG-70 in NMIBC patients BCG-unresponsive and high-risk NMIBC incompletely treated with BCG or BCG-naïve. ClinicalTrials.gov. Last updated November 12, 2025. Accessed December 9, 2025. https://clinicaltrials.gov/study/NCT04752722