Katherine Chan, MD, outlines the design of the pivotal LEGEND trial

Detalimogene voraplasmid (formerly EG-70) is currently under evaluation in the phase 1/2 LEGEND trial (NCT04752722), which is assessing the safety and efficacy of the non-viral gene therapy in patients with non–muscle invasive bladder cancer (NMIBC).¹

In an interview with Urology Times®, Katherine Chan, MD, MPH, walked through the design of the pivotal study.

Specifically, the LEGEND trial is assessing detalimogene across 4 patient cohorts. Cohort 1, which is intended to support the company’s Biologics License Application for detalimogene, is assessing the agent in approximately 100 patients with high-risk BCG-unresponsive NMIBC with CIS with or without papillary disease. The study is also enrolling patients with BCG-exposed NMIBC with CIS (cohort 2a), patients with NMIBC with CIS who have been exposed to BCG but have not received an adequate amount of treatment (cohort 2b), and patients with high-risk BCG-unresponsive NMIBC with papillary-only disease (cohort 3).

Chan is the senior medical director at enGene and a urologist at the University of North Carolina, Chapel Hill.

Patients in the LEGEND study are being enrolled through clinical trial sites across the US, Canada, Europe, and the Asia-Pacific region. Those enrolled in the trial will receive detalimogene at a dose concentration of 0.8 mg/mL in a 4-dose 50 mL instillation schedule at weeks 1, 2, 5, and 6 of a 12-week cycle.

Chan also outlined notable protocol amendments to the trial, which include resection for patients with T1 disease at presentation, as well as the option for reinduction in patients who have progression disease following the end of the 12-week cycle.

The primary end point for the study is the complete response rate at 48 weeks, and the study’s secondary end points are safety and tolerability.

Primary completion of the study is anticipated for June 2026.

REFERENCE

1. LEGEND study: EG-70 in NMIBC patients BCG-unresponsive and high-risk NMIBC incompletely treated with BCG or BCG-naïve. ClinicalTrials.gov. Last updated June 11, 2025. Accessed July 28, 2025. https://clinicaltrials.gov/study/NCT04752722