MORPHEUS Phase II–III Study: A Pre-Planned Interim Safety Analysis and Preliminary Results
Aurélie Garant, Carol‐Ann Vasilevsky, Marylise Boutros, Farzin Khosrow‐Khavar, Petr Kavan, Hugo Diec, Sylvain Des Groseilliers, Julio Faria, É. Ferland, Vincent Pelsser, André‐Guy Martin, Slobodan Dević, T. Vuong
Abstract
BACKGROUND: We explored image-guided adaptive endorectal brachytherapy patients electing non-operative management for rectal cancer. We present the first pre-planned interim analysis. METHODS: In this open-label phase II-III randomized study, patients with operable cT2-3ab N0 M0 rectal cancer received 45 Gy in 25 fractions of pelvic external beam radiotherapy (EBRT) with 5-FU/Capecitabine. They were randomized 1:1 to receive either an EBRT boost of 9 Gy in 5 fractions (Arm A) or three weekly adaptive brachytherapy (IGAEBT) boosts totaling 30 Gy (Arm B). Patient characteristics and toxicity are presented using descriptive analyses; TME-free survival between arms with the intention to treat the population is explored using the Kaplan-Meier method. RESULTS: = 18/20). Median follow-up was 1.3 years; 2-year TME-free survival was 38.6% (95% CI: 16.5-60.6%) in the EBRT arm and 76.6% (95% CI: 56.1-97.1%) in the IGAEBT arm. CONCLUSIONS: Radiation intensification with IGAEBT is feasible. This interim analysis suggests an improvement in TME-free survival when comparing IGAEBT with EBRT, pending confirmation upon completion of this trial.