King of Prussia, Pennsylvania — August 14, 2025 — Leads & Copy — Phio Pharmaceuticals Corp. (NASDAQ: PHIO) announced advancements in its clinical trial for INSTASYL siRNA lead product candidate PH-762, with the fifth cohort now enrolling patients in the ongoing study. The company also reported its financial results for the quarter ended June 30, 2025.
The Phase 1b dose escalation clinical trial (NCT 06014086) evaluates the safety and tolerability of neoadjuvant use of intratumoral PH-762 in Stages 1, 2 and 4 cutaneous squamous cell carcinoma (cSCC), Stage 4 melanoma, and Stage 4 Merkel cell carcinoma. To date, 15 patients with cutaneous carcinomas have been treated across four cohorts. Results show no dose-limiting toxicities or clinically relevant treatment-emergent adverse effects, and PH-762 has been well tolerated.
In cSCC patients, five had a complete response (100% clearance), one a near-complete response (>90% clearance), one a partial response (>50% clearance), and six a pathologic non-response (< 50% clearance). The Merkel cell carcinoma patient had a pathological partial response (>50% clearance), while the melanoma patient was a non-responder (<50% clearance).
Phio also entered into a drug substance development services agreement with a U.S. manufacturing company for analytical and process development and cGMP manufacture of PH-762.
The company presented its INTASYL self-delivering siRNA technology at the Society of Investigative Dermatology (SID) in May 2025 and presented on compounds PH-762 and PH-894 at the 11th Annual Immunotherapy of Cancer (ITOC 11) conference in Munich, Germany, in April 2025. Interim data on the Phase 1b clinical trial was presented at the American Society of Clinical Oncology (ASCO) conference in June 2025.
On July 25, 2025, Phio entered into warrant inducement agreements, raising approximately $2.2 million after expenses.
At June 30, 2025, Phio had cash and cash equivalents of approximately $10.8 million, compared to $5.4 million at December 31, 2024.
Research and development expenses for the three months ended June 30, 2025, were $1.1 million, compared to $0.9 million for the same period in 2024.
General and administrative expenses for the three months ended June 30, 2025, were $1.2 million, compared to $1.0 million for the same period in 2024.
Net loss was $2.2 million for the three months ended June 30, 2025, compared with $1.8 million for the same period in 2024.
Contact: Jennifer Phillips, jphillips@phiopharma.com
Source: Phio Pharmaceuticals Corp.
