The following is a summary of “Ruxolitinib Versus Best Available Therapy for Polycythemia Vera Intolerant or Resistant to Hydroxycarbamide in a Randomized Trial,” published in the July 2023 issue of Oncology by Harrison, et al.
For a MAJIC-PV study, researchers sought to evaluate the efficacy of ruxolitinib compared to the best available therapy (BAT) in patients with polycythemia vera (PV) who were resistant or intolerant to hydroxycarbamide (HC-INT/RES).
The randomized phase II trial included 180 randomly assigned patients to receive either ruxolitinib or BAT. The primary outcome measure was complete response (CR) within 1 year. Secondary outcomes included duration of response, event-free survival (EFS), symptom response, and molecular response.
The study showed that CR was achieved in 43% of patients on ruxolitinib compared to 26% on BAT (odds ratio 2.12, 90% CI: 1.25 to 3.60, P = 0.02). The duration of CR was significantly longer in the ruxolitinib group (hazard ratio [HR] 0.38, 95% CI: 0.24 to 0.61, P < 0.001). Symptom responses were better and more durable with ruxolitinib. Patients who achieved CR within 1 year had superior EFS (HR 0.41, 95% CI: 0.21 to 0.78, P = 0.01), and those on ruxolitinib had better EFS (HR 0.58, 95% CI: 0.35 to 0.94, P = 0.03). As indicated by the JAK2V617F variant allele fraction, the molecular response was more frequent with ruxolitinib and was associated with improved outcomes, including progression-free survival (PFS), EFS, and overall survival (OS). Clearance of JAK2V617F stem/progenitor cells was also observed. ASXL1 mutations were predictive of adverse EFS. The safety profile of ruxolitinib was consistent with previous reports.
The MAJIC-PV study demonstrated that ruxolitinib treatment significantly benefited HC-INT/RES PV patients, including higher CR rates, improved EFS, and molecular response. Furthermore, it revealed the association of molecular response with EFS, PFS, and OS for the first time.