Herpes virus being used to fight melanoma

Researchers are finding success fighting cancer with another virus.

The experimental treatment uses a genetically engineered herpes virus to attack melanoma - the deadliest form of skin cancer.

The approach is called immunotherapy, and researchers said it worked in a phase three clinical trial.

That's the final step of testing before a treatment can receive FDA approval.

Patients who received the drug lived longer and had fewer side effects than chemotherapy.