Oblimersen in the treatment of metastatic melanoma

Abstract

Oblimersen (Genasense®) is a Bcl-2 antisense compound that selectively targets Bcl-2 RNA for degradation by RNase H and thereby decreases Bcl-2 protein production. Bcl-2 protein plays a major role in preventing apoptosis and has been linked to chemotherapy resistance in melanoma. Preclinical studies with oblimersen in melanoma cell lines and xenograft models of melanoma have demonstrated downregulation of Bcl-2 protein, induction of apoptosis and enhanced tumor response when combined with chemotherapy. Results of a Phase I/II study have shown that reducing Bcl-2 with oblimersen coincident with the administration of dacarbazine may amplify apoptosis and improve therapeutic outcome. A subsequent Phase III trial showed that the addition of oblimersen to dacarbazine significantly improved multiple clinical outcomes relative to dacarbazine alone based on an intent-to-treat analysis of progression-free survival and response rate (overall, complete and durable), as well as overall survival in patients with normal lactate dehydrogenase. This article reviews the biochemistry, pharmacodynamics and pharmacokinetics, safety and efficacy data related to oblimersen in melanoma.