Response to the Rechallenge With Talimogene Laherparepvec (T-VEC) After Ipilimumab/Nivolumab Treatment in Patient With Cutaneous Malignant Melanoma Who Initially Had a Progression on T-VEC With Pembrolizumab

Modern approaches to treating cancer with oncolytic viruses

According to the World Health Organization, cancer is the second leading cause of death in the world. This serves as a powerful incentive to search for new effective cancer treatments. Development of new oncolytic viruses capable of selectively destroying cancer cells is one of the modern approaches to cancer treatment. The advantage of this method – the selective lysis of tumor cells with the help of viruses – leads to an increase in the antitumor immune response of the body, that in turn promotes the destruction of the primary tumor and its metastases. Significant progress in development of this method has been achieved in the last decade. In this review we analyze the literature data on families of oncolytic viruses that have demonstrated a positive therapeutic effect against malignant neoplasms in various localizations. We discuss the main mechanisms of the oncolytic action of viruses and assess their advantages over other methods of cancer therapy as well as the prospects for their use in clinical practice.

Combination therapy with immune checkpoint inhibitors (ICIs); a new frontier

Recently, immune checkpoint inhibitors (ICIs) therapy has become a promising therapeutic strategy with encouraging therapeutic outcomes due to their durable anti-tumor effects. Though, tumor inherent or acquired resistance to ICIs accompanied with treatment-related toxicities hamper their clinical utility. Overall, about 60-70% of patients (e.g., melanoma and lung cancer) who received ICIs show no objective response to intervention. The resistance to ICIs mainly caused by alterations in the tumor microenvironment (TME), which in turn, supports angiogenesis and also blocks immune cell antitumor activities, facilitating tumor cells' evasion from host immunosurveillance. Thereby, it has been supposed and also validated that combination therapy with ICIs and other therapeutic means, ranging from chemoradiotherapy to targeted therapies as well as cancer vaccines, can capably compromise tumor resistance to immune checkpoint blocked therapy. Herein, we have focused on the therapeutic benefits of ICIs as a groundbreaking approach in the context of tumor immunotherapy and also deliver an overview concerning the therapeutic influences of the addition of ICIs to other modalities to circumvent tumor resistance to ICIs.

Is there still a role for talimogene laherparepvec (T-VEC) in advanced melanoma? An indirect efficacy comparison of T-VEC plus ipilimumab combination therapy versus T-VEC alone as salvage therapy in unresectable metastatic melanoma

BACKGROUND

Talimogene laherparepvec (T-VEC) improves overall survival (OS) in unresectable stage IIIB/C-IV melanoma T-VEC may have synergistic effects with CTLA-4 inhibitors In the absence of a trial comparing T-VEC and ipilimumab (T-VEC + IPI) to T-VEC, we applied a novel indirect comparison method using extrapolated OS curves to estimate OS outcomes in a simulated trial comparing both regimens in stage IIIB/C-IV unresectable melanoma.

RESEARCH DESIGN AND METHODS

Two trials with extractable OS curves for a T-VEC versus T-VEC + IPI comparison were identified. Outcomes were adjusted for heterogeneity in prognostic factors using a calculated adjustment factor. T-VEC and adjusted/unadjusted T-VEC+IPI curves were plotted with 95% CIs.

RESULTS

Unadjusted indirect OS comparison of T-VEC versus T-VEC + IPI revealed no significant difference up to 15 months. Extrapolation beyond 15 months showed significant survival benefits for T-VEC + IPI over T-VEC, confirmed in adjusted analyses. The expected OS percentage at 48 months is 32.0% (95% CI = 26.6-37.3) for T-VEC, 60.0% (95% CI = 46.2-69.1) for unadjusted, and 81.1% (95% CI = 72.3-85.9) for adjusted T-VEC + IPI.

CONCLUSIONS

Our novel indirect comparison suggests that T-VEC + IPI may demonstrate a significantly improved OS versus T-VEC alone. Findings may portend a possible role for the addition of T-VEC to advanced melanoma treatment regimens in select patients as salvage therapy.

Real-life use of talimogene laherparepvec (T-VEC) in melanoma patients in centers in Austria, Switzerland and Germany

Background

Talimogene laherparepvec (T-VEC) is a licensed therapy for use in melanoma patients of stage IIIB-IVM1a with injectable, unresectable metastatic lesions in Europe. Approval was based on the Oncovex Pivotal Trial in Melanoma study, which also included patients with distant metastases and demonstrated an overall response rate (ORR) of 40.5% and a complete response (CR) rate of 16.6%.

Objectives

The aim of this study was to assess the outcome of melanoma patients treated with T-VEC in a real-life clinical setting.

Methods

Based on data from 10 melanoma centers in Austria, Switzerland and southern Germany, we conducted a retrospective chart review, which included 88 patients (44 male, 44 female) with a median age of 72 years (range 36–95 years) treated with T-VEC during the period from May 2016 to January 2020.

Results

88 patients fulfilled the inclusion criteria for analysis. The ORR was 63.7%. 38 patients (43.2%) showed a CR, 18 (20.5%) had a partial response, 8 (9.1%) had stable disease and 24 (27.3%) patients had a progressive disease. The median treatment period was 19 weeks (range: 1–65), an average of 11 doses (range: 1–36) were applied. 39 (45.3%) patients developed adverse events, mostly mild, grade I (64.1%).

Conclusion

This real-life cohort treatment with T-VEC showed a high ORR and a large number of durable CRs.