Current Status of Biological Therapies for the Treatment of Metastatic Melanoma.

Compared to early-stage melanoma when surgical excision is possible, metastatic disease continues to offer a much grimmer prognosis as traditional chemotherapy treatment regimens offer relatively little survival benefit. This has led to changes in treatment approaches over the preceding two decades as contemporary methods for the treatment of advanced or metastatic melanoma now involve a number of biological modalities, which include immunotherapeutic approaches, targeted therapies and epigenetic modification therapies. Clinically available immunotherapeutic agents include interleukin 2 (IL-2), as well as drugs targeting the important immune checkpoint molecules, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1). The targeted therapeutic agents modulate specific pro-oncogenic mutations such as v-Raf murine sarcoma viral oncogene homolog B (BRAF), receptor tyrosine kinases, MEK inhibitors and potential future therapeutic targets, such as the CDK4/CDK6, PTEN and GNAQ/GNA11 genes. Additionally, an increasing understanding of the role of epigenetic alterations in the development and progression of melanoma now offers a new potential drug target. Several of these agents have shown promising results; however, in many investigations, combinations of different therapeutic approaches, each with different mechanisms of action, have yielded improved outcomes as treatment regimens continue to be further optimized by active research and patient disease sub-group analyses. This review summarizes the novel biological agents and new treatments, directly contributing to the significant improvement of biological therapies and markedly advancing knowledge of clinical application of newly approved and developed therapies in treatment of patients with metastatic melanoma.