Updated interim results from the Phase 2 LEGEND trial show that detalimogene voraplasmid may be an effective treatment for patients with high-risk, BCG-unresponsive non–muscle invasive bladder cancer (NMIBC). The therapy is delivered directly into the bladder to trigger a local immune response against tumors.
The study showed that 54% of patients achieved a complete response at some point during treatment, and 43% maintained that response for at least 6 months. Among patients who responded, 91% showed improvement at their first assessment. Only 3.2% of patients progressed to muscle-invasive bladder cancer, helping many avoid bladder removal surgery. Of those still in complete response at 6 months, 84% remained cancer-free at 9 months.
The treatment also showed a favorable safety profile. Most side effects, including fatigue and urinary symptoms, were mild or moderate. Only 2.4% of patients stopped treatment because of side effects.