FDA Approves First-in-Class Treatment of Melanoma
- By BSTQ Staff
Hailed as a major advancement in the fight against skin cancer, the U.S. Food and Drug Administration (FDA) has approved a new immune-based therapy for treating metastatic melanoma. Amgen’s Imlygic (talimogene laherparepvec), commonly referred to as T-VEC, is among a new class of agents known as oncolytic virus immunotherapies. An oncolytic virus is one that preferentially infects and kills cancer cells. Imlygic is the first therapy in this class to receive FDA approval to treat melanoma.
Imlygic is a version of the herpes simplex virus that has been genetically modified to attenuate the virus, increase selectivity for cancer cells and secrete cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF is a protein that is naturally secreted in the body that can promote an immune response. The virus invades both cancerous and healthy cells, but it is unable to replicate in healthy cells, leaving them unharmed. Inside a cancer cell, the virus is able to replicate, secreting GM-CSF in the process. Eventually overwhelmed, the cancer cell ruptures, which destroys the cell and releases new viruses, GM-CSF and an array of tumor-specific antigens.
“Imlygic offers a two-pronged approach for the treatment of metastatic melanoma. The combination of the virus with GM-CSF increases the drug’s cancer-killing effect while activating the immune system to kill melanoma cells — even those that are distant from the treated tumor,” said Lisa H. Butterfield, PhD, professor of medicine at the University of Pittsburgh and vice president of the Society for Immunotherapy of Cancer. “Imlygic also offers simple administration; it can be injected in an office visit and, importantly, has no serious side effects.”
Prior to the approval of Imlygic, the therapy was extensively studied in clinical trials that indicated the treatment improved durable response rates in patients with advanced melanoma. Durable response rate is defined as partial or complete response to treatment lasting continuously for at least six months.
