Evaluating the effectiveness of T-VEC after failure of immunotherapy in patients with unresectable metastatic melanoma.

This study evaluated the effectiveness of talimogene laherparepvec (Imlygic; T-VEC) after failure of immunotherapy for the treatment of patients with unresectable metastatic melanoma. The data showed that T-VEC after the failure of immunotherapy is safe and effective in these patients.

Melanoma is an aggressive type of skin cancer. It has a high tendency to spread to other parts of the body (metastasis). In stage 3 or 4 melanoma, cancer has spread to nearby lymph nodes. The main form of treatment is the surgical removal of tumors. Tumors that cannot be removed surgically (unresectable) can be difficult to treat. Immunotherapy (treatment that acts on the immune system to attack and kill cancer cells) is commonly used in these patients. Patients with unresectable tumors often have a poorer prognosis.

T-VEC is a recently approved treatment for the treatment of unresectable advanced-stage melanoma. T-VEC is a modified virus. This type of treatment specifically targets cancer cells, leaving healthy cells alone. When injected into a tumor, it splits the cancer cells open. This leads to cancer cell death. However, the effectiveness of T-VEC after the failure of immunotherapy in patients with unresectable metastatic melanoma is still unknown.

This study involved 112 patients with advanced-stage (III or IV) melanoma. Patients were treated with T-VEC as second-or later-line therapy after immunotherapy had failed. The average number of cycles of T-VEC was 6. The average follow-up time was 14 months.

Overall, 51% of the patients responded to the treatment. The complete response rate (complete disappearance of cancer cells) was 37%. The partial response rate (partial disappearance of cancer cells/tumor shrinkage) was 14%.

The average survival without cancer worsening was 14.5 months. The average survival without any signs of cancer was 32 months in patients with a complete response.

64% of the patients did not report any side effects to the treatment. The most common side effects of T-VEC were flu-like symptoms (27%; fatigue, fevers, chills, nausea) and injection site symptoms (7%; skin irritation and infection). Most side effects (72.5% of the 40 patients that reported side effects) were mild. 

This study concluded that T-VEC treatment after failure of immunotherapy was effective and well tolerated in patients with unresectable metastatic melanoma.

This study looked back in time at medical records. Some information might have been missing. Also, the study did not have a control group for comparison.