Genetically Engineered Herpes Virus Shows Promise in Treating Advanced Melanoma

Strategic Insights -

A phase 1-2 clinical trial has found that a genetically modified herpes simplex virus type 1 (HSV-1) can shrink tumors in one-third of patients with advanced melanoma, and nearly one out of six patients have seen tumors completely disappear. This innovative therapy, known as RP1, is a novel class of cancer immunotherapy drugs that target and destroy cancer tumors while generating an anti-tumor immune response. The study's findings are significant because melanoma is the fifth most common cancer for adults, and about half of all advanced melanoma cases cannot be managed with currently available immunotherapy treatments.

Key Takeaways:

  • The genetically modified HSV-1, RP1, was used in a phase 1-2 clinical trial to treat 140 patients with advanced melanoma.
  • One-third of the patients had their tumors shrink by at least 30%, and nearly one out of six patients had tumors completely disappear.
  • The treatment involves injecting RP1 into tumors, which replicates, killing off cancer cells while leaving healthy cells unharmed.
  • RP1 also stimulates the body's white blood cells to seek out and destroy any other cancer cells in the body.
  • The study found that patients' uninjected tumors also shrank or even disappeared, just as frequently and as deeply.
  • The study also found that RP1 was well-tolerated and had a favorable safety outcome.
  • A phase 3 clinical trial, known as IGNYTE-3, has been launched to confirm the findings in a global population of over 400 participants.
  • Keck Medicine will be one of the sites of the clinical trial, with Dr. Gino Kim In heading up the site.

Statistics:

  • 140 patients participated in the phase 1-2 clinical trial.
  • One out of six patients had tumors completely disappear.
  • The treatment involved a combined therapy of RP1 and nivolumab, which was given every two weeks for up to eight cycles.
  • Patients who responded to the treatment continued on nivolumab alone every four weeks for up to 30 cycles (or two years).
  • The study found that patients' uninjected tumors also shrank or even disappeared, just as frequently and as deeply.
  • Over 400 participants are expected to participate in the phase 3 clinical trial, IGNYTE-3.

Sources:

  • Keck Medicine of USC: "Genetically Engineered Herpes Virus Shown to Be Effective in Treating Advanced Melanoma" [Category: Pharmaceuticals, Healthcare, Health Care Services and Facilities, Clinical Trials]
  • Journal of Clinical Oncology: "Phase 1-2 Clinical Trial of RP1 in Patients with Advanced Melanoma"
  • American Society of Clinical Oncology: "2025 Annual Meeting Presentation: RP1 in Patients with Advanced Melanoma"