Melanoma often spreads to cutaneous or subcutaneous sites that are amenable to direct, intralesional injection. As such, developing effective injectable agents has been of considerable interest. Talimogene laherperepvec (T-VEC) is an injectable modified oncolytic herpes virus being developed for the treatment of advanced melanoma. Pre-clinical studies have shown that T-VEC preferentially infects melanoma cells and exerts antitumor activity through directly mediating cell death and by augmenting local and even distant immune responses. T-VEC has now been assessed in Phase II and III clinical trials and has demonstrated a tolerable side-effect profile and promising efficacy, showing an improved durable response rate and a trend toward superior overall survival compared to granulocyte-macrophage colony-stimulating factor. Despite these promising results, responses have been uncommon in patients with visceral metastases. T-VEC is currently being evaluated in combination with other immune therapies (ipilimumab and pembrolizumab) with early signs of activity. In this review, we discuss the preclinical rationale, the clinical experience, and future directions for T-VEC in advanced melanoma.
Keywords: GM-CSF; HSV; T-VEC; immune therapy; injectable; melanoma; oncolytic; talimogene laherperepvec.