Phio Pharmaceuticals Reports 2024 Year End Financial Results and Provides Business Update

In This Article:

Continues advancing clinical trial for INSTASYL siRNA lead product candidate PH-762

3rd Cohort now fully enrolled in on-going clinical study

Marlborough, Massachusetts--(Newsfile Corp. - March 31, 2025) - Phio Pharmaceuticals Corp. (NASDAQ: PHIO) is a clinical-stage biotechnology company developing therapeutics that use its INTASYL® siRNA gene silencing technology designed to make the body's immune cells more effective in killing cancer cells. Phio today reported its financial results for the year ended December 31, 2024, and provided a business update.

Recent Corporate Updates

PH-762 Clinical Progress

PH-762 is currently being evaluated in a U.S. multi-center Phase 1b dose-escalating clinical trial through the intratumoral injection of PH-762 for the treatment of patients with cutaneous squamous cell carcinoma, melanoma and Merkel cell carcinoma. The trial (NCT 06014086) is designed to evaluate the safety and tolerability of neoadjuvant use of intratumorally injected PH-762 in up to 30 patients to assess tumor response and determine the dose or dose range for continued study of PH-762 in future trials. In May and December 2024, respectively, a Safety Monitoring Committee (SMC) reviewed data from the first and second dose cohorts treated with PH-762, and in both instances recommended escalation to the next dose concentration. A total of 7 patients with cutaneous carcinomas have been enrolled in dose cohorts 1 and 2. The second cohort enrolled a total of 4 patients, all of whom were diagnosed with cutaneous squamous cell carcinoma. At Day 36 (tumor excision), a complete response (100% tumor clearance) was reported for 2 patients, a partial response (90% tumor clearance) was reported for 1 patient and 1 patient had stable disease, having not progressed. Patients in the first cohort maintained stable disease.

To date, intratumoral injection of PH-762 has been well tolerated in all enrolled patients. There were no dose-limiting toxicities or clinically relevant treatment-emergent adverse effects in the patients receiving intratumoral PH-762. The third dose cohort is fully enrolled and patients in this cohort are currently in the treatment or follow-up phase of the study. Phio expects to complete enrollment of all patients in the study in the third quarter of 2025.

Capital Sourcing

In December 2024 and January 2025, Phio raised an aggregate of approximately $9.2 million in registered direct offerings and concurrent private placements, before deduction of commissions and other expenses. Additional gross proceeds of approximately $2.9 million were raised from the exercise of warrants previously issued on July 12, 2024. With these proceeds, the Company now believes it has sufficient capital to complete the treatment phase of the Phase 1b trial.