PCN1 PROGNOSTIC FACTORS ASSOCIATED WITH REAL WORLD PROGRESSION-FREE SURVIVAL (PFS) AND OVERALL SURVIVAL (OS) IN PATIENTS WITH BRAF V600 MUTATION-POSITIVE ADVANCED MELANOMA TREATED WITH COBIMETINIB COMBINED WITH VEMUIRAFENIB, USING SURVIVAL DECISION TREE TECHNIQUE

Abstract

Treatment with cobimetinib (C) combined with vemurafenib (V) was used in France in 2015 through a ‘Temporary Authorization for Use’ program (TAU, pre-approval access) and it was marketed on January 2016 for adult patients (pts) with BRAF V600 mutation-positive (+) advanced melanoma. This study aimed to provide real-world effectiveness for a relevant time in pts previously registered in the C TAU. This non-interventional, ambispective, multicenter French study was conducted from 10/2016 to 08/2018 in pts with BRAF V600+ advanced melanoma, with an 18-month follow-up after inclusion. To search for factors associated with survival results (OS and PFS evaluated by Kaplan-Meier method), survival trees were grown on the analysed pts with all baseline covariates. Two control fixed parameters (a maximum depth of 3 successive splits and a minimum of 60 pts in each terminal node) were used in the analyses. Mean age of the 185 evaluable pts was 57±13 years; 63% were men. 159 pts (88%) had disease stage IV. Eastern Cooperative Oncology Group (ECOG) score was ≥2 in 10% of pts (11/114). Prior therapies included surgery (90%), radiation therapy (28%). Median C duration was 14.0 months (mo) (interquartile range: 5.8-18.7). Median OS was 16.1 mo [95%CI 12.5-20.7] and median PFS was 7.3 mo [95%CI 5.2-8.4]. Disease stage IV-M1c (or missing; n=118 pts) was shown to be associated with a shorter median OS, 9.3 mo. Identical groups of pts were shown for the factors associated to PFS: disease stage IV-M1c (or missing; n=118 pts) was shown to be associated with a shorter median PFS compared to other pts (n=67): 4.5 mo and 12.0 mo, respectively. Using survival decision trees, disease stage IV-M1c was shown to be the factor associated with shorter OS and PFS.