Protagonist Therapeutics announces data from REVIVE study at ASH

Protagonist Therapeutics (PTGX) announced details from a poster presentation with final data from the rusfertide Phase 2 REVIVE study. Rusfertide, a mimetic of the natural hormone hepcidin, has potential therapeutic value in the treatment of polycythemia vera, or PV, and other disease indications. The data were presented at the 66th American Society of Hematology, or ASH. Final results show that rusfertide, when added to therapeutic phlebotomy with or without cytoreductive therapy achieved long term durable control of hematocrit below the 45% threshold for over three years. Prior to enrollment, the estimated mean phlebotomy rate in patients who enrolled on study was greater than5/year: In Part 1, the EPHL was less than1/year in patients who received rusfertide. In Part 2, the EPHL was less than1/year and approximately 6.1/year in the rusfertide and placebo groups, respectively. For patients who continued to Part 3, the EPHL remained at less than1/year. Increased mean corpuscular volume and showed continued improvement and normalization of serum ferritin levels. Platelet levels increased following initiation of rusfertide therapy and stabilized over time; mean leukocyte counts remained stable throughout the study. The Myeloproliferative Neoplasm Symptom Assessment Form was used to assess mean change from baseline in the individual symptom score in patients with moderate or severe symptoms at baseline. In patients who had moderate or severe symptoms at baseline, there were significant improvements from baseline in fatigue, early satiety, abdominal discomfort, inactivity, problems with concentration, night sweats, and itching at the end of Part 3. Overall, 18 patients experienced serious adverse events, or SAEs; most SAEs were unrelated and likely associated with the underlying disease. One patient developed acute myeloid leukemia after treatment discontinuation. After more than 150 patient-years of rusfertide exposure, malignancies were reported in 11 patients; all of these patients had risk factors that may have contributed to development of these malignancies. There was no obvious correlation between increased exposure to rusfertide and malignancies reported. Seven thrombotic events occurred in 6 patients; all had high-risk PV. No thrombotic events have been reported in patients with low-risk PV,