ADJUSTMENT FOR SUBSEQUENT THERAPIES RECEIVED- THE IMPACT ON OUTCOMES OF AN ECONOMIC MODEL OF NIVOLUMAB+IPILIMUMAB IN FIRST LINE RENAL CELL CARCINOMA
Author(s)
Cawston H1, Genestier V2, Dale P3, Doan J4, Malcolm B3
1Amaris, Pantin, France, 2Amaris, Levallois-Perret, France, 3Bristol-Myers Squibb, Uxbridge, UK, 4Bristol-Myers Squibb, Princeton, NJ, USA
OBJECTIVES: Treatments received in subsequent lines after progression in randomised clinical trials do not necessarily reflect real world practices across countries. Taking the example of a cost-effectiveness (CE) analysis of nivolumab+ipilimumab in intermediate to poor prognosis patients with previously untreated metastatic renal cell carcinoma, the aim was to evaluate additional statistical analyses, and their impact on the outcomes of the CE model. METHODS: The analyses were based on the Checkmate 214 trial. Kaplan-Meier data were analysed to identify which subgroups of patients could be used. Parametric models were compared to model overall survival, using dependent and independent fittings by group of treatments received. Three subgroups were considered following first line use of sunitinib: those who received nivolumab, those who received another systemic therapy and those who did not or did not progress. All three arms were analyzed conjointly, and the most appropriate model was found to include treatment subgroup as covariate, using the generalised gamma distribution. No subgroup could have been identified for the nivolumab+ipilimumab arm. These subgroups were then incorporated into the CE model. We compared the outcomes of patients, in terms of survival, life years (LYs) and Quality Adjusted Life Years (QALYs). RESULTS: OS was superior for sunitinib patients who received nivolumab as a subsequent therapy with 65% of patients alive at 24 months, compared with 48% for sunitinib patients who did not receive a subsequent therapy and 53% for sunitinib patients who received a systemic therapy. When all sunitinib patients receive nivolumab as second line, sunitinib costs increased by 46% and QALYs increased by 6%. The ICER of nivolumab+ipilimumab versus sunitinib decreased by 24%, over a 40 year time horizon. CONCLUSIONS: Subsequent therapies had an impact on OS, and their adjustment to real world practice can be useful to account for when modelling long-term outcomes of patients.
Conference/Value in Health Info
2018-11, ISPOR Europe 2018, Barcelona, Spain
Value in Health, Vol. 21, S3 (October 2018)
Code
PRM118
Topic
Methodological & Statistical Research
Topic Subcategory
Modeling and simulation
Disease
Urinary/Kidney Disorders