Neoadjuvant T-VEC efficacy consistent at five years for Resectable Melanoma
Sep 11, 2022 | DelveInsight
Neoadjuvant therapy improves survival, surgical resectability, local control, and organ preservation. Other advantages may include the ability to evaluate the clinical and pathologic responses and the potential to identify immunologic and histologic correlates of tumor response. It has also been observed that neoadjuvant immunotherapy with HDI and ipilimumab has yielded several important findings, and multiple studies involving newer immunotherapeutic and targeted agents and combinations are underway. Despite yielding such advantages still, there are no approved therapies for the neoadjuvant treatment of melanoma patients. So there is a high unmet need for neoadjuvant therapy in patients with melanoma.
At the final 5-year analysis of the open-label study, the 5-year relapse-free survival (RFS) rate was 22.3% with T-VEC before surgery, compared with 15.2% for surgery alone. At 5 years, 77.3% of patients treated with T-VEC before surgery were alive compared with 62.7% with surgery alone. The event-free survival (EFS) rate at 5 years was 43.7% with T-VEC vs 62.7% with surgery alone. The baseline characteristics were balanced between arms for T-VEC plus surgery and surgery alone. In the T-VEC arm, the median age was 63.5 years and nearly two-thirds were male (64.5%). The most common ECOG score was 0 (88.2%) and the disease stages were well balanced, with the most common stage being IIIC. Most patients had received a prior surgery for melanoma (93.4%) and a minority had received radiotherapy (5.3%). There were more patients enrolled in this study with in-transit melanoma than in other neoadjuvant studies. There were 21.1% of patients in the combination arm with in-transit disease and 23% in the surgery arm.
Conclusion- T-VEC is administered as a local injection directly to the tumor site. The therapy consists of the herpes simplex 1 virus that has been genetically modified to secrete the cytokine GM-CSF, which causes cell lysis. Additionally, the lysis results in the release of tumor-derived antigens resulting in the activation of an immune response. There is both activation of T cells and natural killer cells with T-VEC. Also, as we already know that T-VEC is approved in a 1L setting for melanoma patients recurrent after initial surgery, so chances are more that this drug will do better even in this patient segment.
Expert Opinion: “The primary endpoint was relapse-free survival, and this was not the conventional relapse-free survival. It does not only count all the local, regional, and distant recurrences, but it also counts all the patients who withdrew to go to surgery and all the R1 and R2 resections“