A Phase 1 interventional study of PH-762 in Squamous Cell Carcinoma of the Skin, Malignant Melanoma of Skin and Merkel Cell Carcinoma of Skin, sponsored by Phio Pharmaceuticals Inc.. Completed at 5 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-21.
Sponsored by Phio Pharmaceuticals Inc. · Phase 1, Interventional, and Treatment
The goal of this clinical trial is to evaluate the safety and tolerability of intratumoral injections of PH-762 in squamous cell carcinoma, melanoma, or Merkel cell carcinomas of the skin, to understand what the body does to the PH-762, and to observe how the tumor responds to the drug. Participants will receive four injections of PH-762 at weekly intervals, into a single tumor, followed by surgical removal of the tumor approximately two weeks later.
PH-762 is a potent RNAi molecule targeting PD-1. PH-762 can inhibit the immune checkpoint PD-1 in the tumor and thereby impede tumor growth. As a preoperative therapy, it may decrease the lesion size and has the potential to improve surgical morbidity. Intratumoral immunotherapy aims to use the tumor as a 'self-vaccine'. The local immune stimulation can induce robust priming of an anti-tumor immune response while generating systemic (abscopal) tumor responses, mediated by properly activated anti-tumor immune cells in the circulation. Local delivery of immunotherapy is expected to minimize systemic exposure and off-target toxicities.
This is a non-comparative study of neoadjuvant monotherapy using PD-1 targeting self-delivering RNAi (PH-762) in adult subjects with cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma. The study treatment consists of four intratumoral injections of PH-762 at weekly intervals, into a single tumor lesion. Excision of the tumor will occur approximately two weeks following the fourth dose of IT PH-762, and the subjects will be followed for an additional 11 weeks.
3,006 studies on the registry are indexed under Melanoma; 520 are open to participants now.
This study's enrollment of 22 is below the median of 38 across 2,351 interventional studies indexed under Melanoma.
Browse Melanoma studies →This is the only study on the registry with Phio Pharmaceuticals Inc. as lead sponsor.
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Key Inclusion Criteria:
Histologically confirmed cutaneous squamous cell carcinoma (cSCC), melanoma, or Merkel cell carcinoma, meeting one of the following criteria:
Key Exclusion Criteria:
Escalating doses of PH-762 are to be tested, with an observation period between doses.
Drug: PH-762
PH-762 is a potent RNAi molecule targeting PD-1.
Adverse Events
Incidence, severity, seriousness and relatedness of all treatment-emergent adverse events.
Time frame: 16 weeks
Pharmacokinetics: maximum plasma concentration (Cmax)
Maximum concentration of PH-762 following intratumoral injection.
Time frame: 3.5 weeks
Pharmacokinetics: time to maximum plasma concentration (Tmax)
Time to maximum concentration of PH-762 following intratumoral injection.
Time frame: 3.5 weeks
Pharmacokinetics: area under the curve to last quantifiable plasma concentration (AUClast)
Exposure to PH-762 through last quantifiable concentration following intratumoral injection.
Time frame: 3.5 weeks
Pathologic response
Pathological response will be assessed by relative amount of viable tumor in resection specimens of the treated lesion.
Time frame: 5 weeks
Tumor burden
Change in tumor burden will be assessed per RECIST/ iRECIST guidelines for the treated lesion.
Time frame: 5 weeks
Plan to share: No
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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