Phio’s PH-762 Yields 85% Response and No Dose-Limiting Toxicities
In Phio’s Phase 1b skin cancer trial, PH-762 achieved an 85% pathological response at the highest dose, including complete tumor clearance in four of six responders, with no dose-limiting toxicities among 22 patients across five escalation cohorts. FDA submission for proposed Phase 2 study design is targeted for Q2 2026.
1. Safety Monitoring Committee Findings
The Safety Monitoring Committee completed its review of all 22 patients treated with PH-762, finding no dose-limiting toxicities or serious adverse events across five dose-escalation cohorts. Patients received four intratumoral injections and were followed for at least four weeks post-treatment.
2. Efficacy Outcomes at Highest Dose
At the maximum drug concentration in cohort five, six of seven patients achieved a pathological response, with four of those responders showing complete tumor clearance. Overall response rate for cutaneous squamous cell carcinoma patients was revised to 65%, including major and partial responses.
3. Next Steps and Timeline
Phio plans an FDA submission in Q2 2026 to propose Phase 2 study design for PH-762, while CMC material for non-human primate studies is expected in March 2026. Successful CMC completion will support cGMP manufacturing in the second half of 2026.