A recent phase II trial evaluated the efficacy of rusfertide in reducing and controlling hematocrit levels in patients with polycythemia vera (PV) requiring therapeutic phlebotomy (TP). The hepcidin mimetic successfully maintained hematocrit at less than 45% and was well tolerated in the study population.
In an abstract presented at the 64th American Society of Hematology Annual Meeting and Exposition, the research team presented the treatment-emergent adverse event (TEAE) profile of the study participants.
Rusfertide was not associated with any grade 4 or 5 TEAEs. Grade 3 events were limited.
The researchers compared incidence of grade 3 TEAEs between patients deemed to be at high risk of thrombotic events due to age or prior events and patients considered to be at low risk. They found that the incidence of grade 3 TEAEs was similar between groups, with the high-risk group more likely to experience fatigue, rash, and paresthesia and the low-risk group more likely to experience hyperuricemia.
The results were also compared between 2 different treatment groups. Group 1 received subcutaneous rusfertide (10-120 mg) along with TP, and group 2 received subcutaneous rusfertide (10-120 mg) along with TP and prior cytoreductive agents. Overall incidence of grade 3 TEAEs was 11% in group 1 and 15% in group 2. Group 1 was more likely to experience contusions and fatigue, and group 2 was more likely to experience dyspnea.
Several patients in group 1 experienced clinically insignificant increases in platelet count that resolved with discontinuation of rusfertide. Of interest, the increase in platelet count was not dependent on dose or duration of rusfertide treatment or on clinical sequelae.
Secondary malignancies were observed in 5 patients, all of whom were in group 2. The prior cytoreductive treatments were considered causative in 4, and 1 was confirmed as a preexisting lesion. All were nonmelanomatous skin cancers.
“These data suggest that the rusfertide TEAE profile is manageable across the range of PV patients,” the researchers concluded.
Pemmaraju N, Verstovsek S, Kremyanskaya M, et al. Subgroup analysis of adverse events following rusfertide dosing in Revive: a phase 2 study of patients with polycythemia vera. Abstract #3040. Presented at the 64th ASH Annual Meeting and Exposition; December 10-13, 2022; New Orleans, Louisiana.