In patients with polycythemia vera receiving standard of care therapy, adding rusfertide to treatment continued to yield a statistically significant reduction in the mean number of phlebotomies and improved hematocrit control, as well as better patient-reported outcomes, according to updated (part 1b) results from VERIFY, a phase 3, double-blind, placebo-controlled study.
The results were presented at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition in Orlando, Florida.
Earlier results from part 1a, which were reported in June 2025 at a plenary session at the 2025 ASCO® Annual Meeting in Chicago, demonstrated control of hemocrit <45% and a relative absence of phlebotomies up to week 32. The new part 1b results extend these results to week 52, demonstrating durable and sustained benefits across all subgroups, including age, PV risk category, and ongoing cytoreductive therapy. Similar findings were also observed after patients crossed over from placebo to rusfertide.
Rusfertide, which has received Breakthrough Therapy Designation, Orphan Drug Designation and Fast Track Designation from the US Food & Drug Administration, is a subcutaneous, self-injected, first-in-class peptide hepcidin mimetic that decreases erythrocytosis. The ongoing VERIFY trial is designed to assess rusfertide versus placebo in phlebotomy-dependent patients with PV receiving SOC.
The VERIFY trial, led by Andrew Kuykendall, MD, of Moffitt Cancer Center in Tampa, Florida, recruited patients requiring frequent phlebotomies with or without stable cytoreductive therapy to control hematocrit.
In the part 1b results, the proportion of patients who continued to have an absence of phlebotomy eligibility between weeks 0-52 (ie, patients initially randomized to rusfertide with durable response through the end of part 1b) was 61.9% (n=91/147).
In patients originally randomized to placebo who crossed over to rusfertide at week 32, the proportion of patients who achieved absence of phlebotomy eligibility was 32.9% (n=48/146) and 78.0% (n=110/141) in parts 1a (weeks 20-32) and 1b (weeks 40-52), respectively.
Mean hemocrit remained <43% throughout part 1b in patients who continued rusfertide and those who switched from PBO to rusfertide.
In terms of patient-reported outcomes, patients treated with rusfertide maintained a statistically significant improvement in the PROMIS Fatigue Short Form 8a (SF-8a) total T-score and MFSAF v4.0 Total Symptom Score.
Rusfertide’s safety profile in part 1b was consistent with prior observations, according to the researchers.
Reference
Kuykendall A, Bankar A, Pettit K. Rusfertide or placebo plus current standard-of-care therapy for polycythemia vera: Durability of response and safety results through week 52 from the randomized controlled phase 3 VERIFY study. Abstract #81. Presented at the 67th American Society of Hematology Annual Meeting and Exposition; December 6-9, 2025; Orlando, Florida.
