Phio Pharmaceuticals Corp. announced that the first patient has been dosed in the Phase 1b clinical trial of PH-762, an INTASYL compound that reduces the expression of PD-1, a protein that inhibits T cells? ability to kill cancer cells.

This clinical trial 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 in patients with cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma. The Phase 1b trial is a non-comparative study of neoadjuvant monotherapy using PH-762 in adult patients with cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma. The study treatment consists of four intratumoral injections of PH-762 at weekly intervals within a single tumor lesion.

Excision of the tumor occurs approximately two weeks following the fourth intratumoral dose of PH-762. Escalating doses of PH-762 are to be tested in separate cohorts. The clinical study is expected to enroll up to 30 patients and will be conducted across 4 to 6 centers in the United States.