Phio Pharmaceuticals Corp. announced that the U.S. Food and Drug Administration (FDA) has cleared the Company's Investigational New Drug (IND) application to proceed with a clinical trial of Phio's lead product candidate, PH-762. PH-762 is an INTASYL compound that reduces the expression of PD-1, a protein that inhibits T cells' ability to kill cancer cells.

Phio plans to initiate its Phase 1b clinical trial of intratumoral PH-762 in patients with cutaneous squamous cell carcinoma, melanoma and Merkel cell in the second half of 2023. The initial multi-center, dose-escalating, Phase 1b clinical trial under Phio's cleared IND is designed to evaluate the safety and tolerability of neoadjuvant use of intratumorally injected PH-762, assess the tumor response, and determine the dose or dose range for continued study of PH-762. Phio will focus its efforts on the U.S. clinical trial and intends to wind down its first-in-human clinical trial for PH-762 in France, which was limited to the treatment of patients with metastatic melanoma.

PH-762 has also received clearance to proceed under an IND sponsored by AgonOx Inc. in a clinical trial evaluating PH-762 treated "double positive" (DP) CD8 tumor infiltrating lymphocytes (TIL) in patients with melanoma and other advanced solid tumors.