FLORENCE, Italy and NEW YORK, June 14, 2026
Menarini Group and its oncology-focused subsidiary Stemline Therapeutics have announced promising new results from the pivotal Phase 3 SENTRY trial, demonstrating that the combination of selinexor and ruxolitinib significantly improved clinical outcomes in patients with frontline myelofibrosis (MF). Presented as a late-breaking oral presentation at the European Hematology Association (EHA) 2026 Congress, the data highlight the potential of the investigational combination to become an important new treatment option for patients suffering from this rare and life-threatening blood cancer. The study met its first co-primary endpoint by achieving a statistically significant improvement in spleen volume reduction of at least 35% (SVR35), one of the most clinically meaningful measures in myelofibrosis management. Researchers also reported encouraging early overall survival trends and evidence supporting the potential disease-modifying effects of the therapy, further strengthening its clinical profile.
Phase 3 Trial Achieves Significant Spleen Volume Reduction
The randomized, double-blind, placebo-controlled SENTRY trial enrolled 353 patients with frontline myelofibrosis and compared selinexor plus ruxolitinib against ruxolitinib monotherapy. Results showed that nearly 50% of patients receiving the combination therapy achieved SVR35 at Week 24, compared with 28% of patients receiving standard treatment alone. Importantly, the clinical benefit was observed rapidly and remained durable throughout the study period. At Week 12, SVR35 was achieved by 49.4% of patients receiving the combination versus 20.3% in the control arm, while at Week 36, response rates remained strong at 46.9% versus 23.0%, respectively.
Investigators emphasized that spleen reduction remains one of the primary treatment goals in myelofibrosis because enlarged spleens contribute significantly to symptom burden and disease complications. The robust and sustained responses observed in the selinexor arm suggest the therapy may offer meaningful clinical improvements for patients facing limited treatment options.
Early Survival Signals and Disease Modification Potential
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Beyond spleen reduction, researchers reported encouraging evidence that the therapy may influence long-term disease outcomes. Although overall survival data remain immature, the study demonstrated a greater than 50% reduction in the risk of death, with a hazard ratio of 0.43 favoring the combination arm. Additional post-hoc analyses from both the Phase 3 and earlier Phase 1 SENTRY studies suggested a potential relationship between achieving SVR35 and improved overall survival. The trial also showed favorable results for variant allele frequency (VAF) reduction, an exploratory biomarker associated with disease modification.
At Week 24, 32% of patients treated with selinexor plus ruxolitinib achieved VAF reductions compared with 23.9% of patients receiving ruxolitinib alone. Researchers believe these findings may indicate the therapy’s ability to impact the underlying biology of myelofibrosis rather than solely controlling symptoms. Such disease-modifying activity represents a major objective in the development of next-generation treatments for myeloproliferative neoplasms.
Manageable Safety Profile Supports Clinical Development
Safety and tolerability findings were consistent with the established profiles of both selinexor and ruxolitinib. Investigators reported no new safety concerns, and the combination demonstrated a manageable adverse event profile throughout the study. While the second co-primary endpoint evaluating Absolute Total Symptom Score (Abs-TSS) was not met, symptom improvements remained comparable between treatment groups, indicating that the addition of selinexor did not compromise patient-reported outcomes. The overall benefit-risk profile observed in the trial has generated optimism among clinicians and researchers seeking more effective therapies for myelofibrosis, a disease associated with a median survival of approximately six years following diagnosis.
With strong spleen response rates, encouraging survival trends, and evidence supporting potential disease modification, the SENTRY results position selinexor plus ruxolitinib as a promising investigational combination that could reshape future treatment strategies for patients living with myelofibrosis.
Source: Menarini Group press release
