Talimogene Laherparepvec for Treating Metastatic Melanoma: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

Abstract

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Amgen) of talimogene laherparepvec (T-VEC) to submit clinical and cost-effectiveness evidence for previously untreated advanced (unresectable or metastatic) melanoma as part of the Institute’s Single Technology Appraisal process. The Liverpool Reviews and Implementation Group (LRiG) at the University of Liverpool was commissioned to act as the Evidence Review Group (ERG). This article presents a summary of the company’s submission of T-VEC, the ERG review and the resulting NICE guidance (TA410), issued in September 2016. T-VEC is an oncolytic virus therapy granted a marketing authorisation by the European Commission for the treatment of adults with unresectable melanoma that is regionally or distantly metastatic (stage IIIB, IIIC and IVM1a) with no bone, brain, lung or other visceral disease. Clinical evidence for T-VEC versus granulocyte–macrophage colony-stimulating factor (GM-CSF) was derived from the multinational, open-label randomised controlled OPTiM trial [Oncovex (GM-CSF) Pivotal Trial in Melanoma]. In accordance with T-VEC’s marketing authorisation, the company’s submission focused primarily on 249 patients with stage IIIB to stage IV/M1a disease who constituted 57% of the overall trial population (T-VEC, n = 163 and GM-CSF, n = 86). Results from analyses of durable response rate, objective response rate, time to treatment failure and overall survival all showed marked and statistically significant improvements for patients treated with T-VEC compared with those treated with GM-CSF. However, GM-CSF is not used to treat melanoma in clinical practice. It was not possible to compare treatment with T-VEC with an appropriate comparator using conventionally accepted methods due to the absence of comparative head-to-head data or trials with sufficient common comparators. Therefore, the company compared T-VEC with ipilimumab using what it described as modified Korn and two-step Korn methods. Results from these analyses suggested that treatment with T-VEC was at least as effective as treatment with ipilimumab. Using the discounted patient access scheme (PAS) price for T-VEC and list price for ipilimumab, the company reported incremental cost-effectiveness ratios (ICERs) per quality-adjusted life-year (QALY) gained. For the comparison of treatment with T-VEC versus ipilimumab, the ICER per QALY gained was −£16,367 using the modified Korn method and −£60,271 using the two-step Korn method. The NICE Appraisal Committee (AC) agreed with the ERG that the company’s methods for estimating clinical effectiveness of T-VEC versus ipilimumab were flawed and therefore produced unreliable results for modelling progression in stage IIIB to stage IVM1a melanoma. The AC concluded that the clinical and cost effectiveness of treatment with T-VEC compared with ipilimumab is unknown in patients with stage IIIB to stage IV/M1a disease. However, the AC considered that T-VEC may be a reasonable option for treating patients who are unsuitable for treatment with systemically administered immunotherapies (such as ipilimumab). T-VEC was therefore recommended by NICE as a treatment option for adults with unresectable, regionally or distantly metastatic (stage IIIB to stage IVM1a) melanoma that has not spread to bone, brain, lung or other internal organs, only if treatment with systemically administered immunotherapies is not suitable and the company provides T-VEC at the agreed discounted PAS price.