Matching-adjusted indirect treatment comparison in patients with radioiodine-refractory differentiated thyroid cancer

Abstract

Matching-adjusted indirect treatment comparison in patients with radioiodine-refractory differentiated thyroid cancer Gabriel Tremblay,1 Tim Holbrook,2 Gary Milligan,2 Corey L Pelletier,1 Petra Rietschel1 1Eisai Inc, Woodcliff Lake, NJ, USA; 2Adelphi Real World, Manchester, UKAims: Lenvatinib and sorafenib have been evaluated in separate Phase III placebo-controlled trials in patients with radioiodine-refractory differentiated thyroid cancer; however, no head-to-head comparative studies are available. We performed an indirect comparison of these agents using matching-adjusted indirect comparison (MAIC) to adjust for differences in baseline characteristics, a technique allowing comparison of two studies with patient-level data available for one but only aggregate data available for the other.Patients and methods: Individual patient data were available for the SELECT trial (lenvatinib versus placebo) whereas only published summary data were available for the DECISION trial (sorafenib versus placebo); therefore the SELECT data were adjusted to closely match the DECISION data. Data for patients in SELECT were assigned weights so that weighted mean baseline characteristics of the SELECT population matched those reported for DECISION. Adjusted hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS; corrected for crossover using rank-preserving structural failure time models) were calculated using weighted Cox regression models. Adjusted HRs were used to calculate indirect HRs with 95% confidence intervals (CIs).Results: Indirect treatment comparison using unadjusted clinical trial data resulted in an HR for PFS of 0.36 (95% CI 0.22–0.57) for lenvatinib versus sorafenib; MAIC resulted in an HR of 0.33 (95% CI 0.20–0.53), suggesting a statistically significantly superior PFS for lenvatinib. The HR for crossover-corrected OS for lenvatinib versus sorafenib was 0.77 (95% CI 0.44–1.35); MAIC resulted in an OS HR of 0.73 (95% CI 0.40–1.35).Conclusion: After adjusting for differences in baseline characteristics using MAIC, lenvatinib was associated with statistically significantly superior PFS compared with sorafenib in patients with radioiodine-refractory differentiated thyroid cancer. This suggests lenvatinib may provide superior efficacy compared with sorafenib for patients with radioiodine-refractory differentiated thyroid cancer. Keywords: indirect comparison, lenvatinib, overall survival, progression-free survival, radioiodine-refractory, sorafenib