New Skin Cancer Injection Shows Early Promise
Adults with common skin cancers may one day have an option to shrink tumors before surgery, though the drug is still in early testing.
Updated on Nov. 6, 2026 in Cancer
Phio Pharmaceuticals will present clinical data from its Phase 1b trial of INTASYL PH-762, an investigational injection for skin cancers, at the 41st Annual Meeting of the Society for Immunotherapy of Cancer in Phoenix, Arizona, November 6-8, 2026. The data concern patients with cutaneous squamous cell carcinoma, melanoma and Merkel cell carcinoma.
Why it matters
Skin cancers are commonly treated with surgery, so a drug given before surgery that could shrink tumors would give patients and physicians another option. The data are being shared at a major immunotherapy conference, which is where early-stage results are typically first reviewed by the research community.
The data come from a Phase 1b trial, an early-stage study that primarily assesses safety and preliminary activity, evaluating PH-762 in cutaneous squamous cell carcinoma, melanoma and Merkel cell carcinoma. Specific efficacy and safety numbers were not part of the information available for this report, and the findings are preliminary.
The players
Phio Pharmaceuticals Corp.
A clinical-stage siRNA biopharmaceutical company traded on NASDAQ under PHIO, developing gene-silencing treatments including INTASYL PH-762 for cancer.
Society for Immunotherapy of Cancer (SITC)
A professional society that hosts an annual meeting focused on cancer immunotherapy research and clinical development.
John Strasswimmer, M.D., Ph.D.
The lead investigator for the Phase 1b trial of PH-762, presenting the study data at the SITC meeting.
The details
PH-762 is designed to silence the PD-1 gene, which is implicated in several forms of skin cancer, using siRNA gene-silencing technology. It is delivered as a neoadjuvant intratumoral injection, meaning it is given directly into the tumor before surgery. The approach aims to enhance the body's own immune cells so they can better recognize and attack cancer cells.
Timeline
November 6-8, 2026: Phio presents Phase 1b data at the 41st SITC Annual Meeting in Phoenix, Arizona.
First half of 2027: A Phase 2b study of PH-762 is planned.
Health Landscape
Current standard treatment for cutaneous squamous cell carcinoma relies on Mohs micrographic surgery and/or standard excision. An injectable, pre-surgical option that acts on the immune system would add a tissue-sparing alternative to that established approach.
If you have a history of skin cancer or notice a new or changing skin lesion, it is worth raising with your dermatologist, since treatment options continue to evolve. This is early-stage research, so it does not change current care, and any questions about available options should be discussed with your doctor.
The takeaway
Early-stage research on an injectable, siRNA-based treatment for skin cancers is moving toward larger studies. Readers with questions about skin cancer treatment options should discuss them with their physician or dermatologist.
What happens next
A Phase 2b study of PH-762 is planned for the first half of 2027.
Further reading
For more background on how these treatments are evaluated, see the Cancer section.
