For patients with primary or secondary myelofibrosis (MF) who have already received ruxolitinib, momelotinib (MMB), an oral JAK inhibitor, was not superior to best available therapy (BAT) in reducing spleen volume, but was significant in improving disease-related symptoms, according to data from SIMPLIFY-2 (ClinicalTrials.gov Identifier: NCT02101268) presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.1
In this study, patients were randomly assigned to receive MMB (104 patients) or BAT (52 patients) for 24 weeks. MMB 200 mg was given once daily. For 88% of patients on BAT, treatment included ruxolitinib.
Spleen volume was assessed by MRI and patient-reported symptoms (Total Symptom Score; TSS) were assessed using the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF).
The primary endpoint was splenic response rate (SRR; at least 35% reduction in volume from baseline) at 24 weeks. Secondary endpoints were TSS response rate (at least 50% reduction from baseline), and red blood cell transfusion independence (TI) and dependence (TD).
At 24 weeks, 70% and 77% of patients in the MMB and BAT arms, respectively, completed treatment.
After 24 weeks, MMB was not superior to BAT: SRR was 6.7% for MMB and 5.8% for BAT (P = .90).
TSS rates were, however, 26.2% for MMB and 5.9% for BAT (P < .001); TI rates were 43.3% for MMB and 21.2% for BAT (P = .001).
The most common grade 3 or worse event in patients on MMB was anemia (13%), while grade 3 or worse adverse events for patients on BAT included anemia (13%), thrombocytopenia (6%), and abdominal pain (6%).
Any-grade neuropathy was reported in 11% of patients on MMB and none on BAT.
The authors concluded that “24 weeks of MMB was not superior to BAT for SRR, but significantly better in improving disease related symptoms and transfusion independence.”
- Harrison CN, Vannucchi AM, Platzbecker U, et al. Phase 3 randomized trial of momelotinib (MMB) versus best available therapy (BAT) in patients with myelofibrosis (MF) previously treated with ruxolitinib (RUX). J Clin Oncol. 2017;35(suppl; abstr 7001).
This article originally appeared on Cancer Therapy Advisor