|The following article features coverage from the European Hematology Association 2020 virtual meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Treatment of patients with low-risk polycythemia vera (PV) with ropeginterferon alfa-2b improved symptoms and reduced the number of phlebotomies compared with the standard of care, according to results of a phase 2 trial presented at the Virtual Edition of the 25th European Hematology Association (EHA) Annual Congress.
Patients with PV have a higher risk of thrombotic events than the general population with or without multiple risk factors, Tiziano Barbui, MD, of Ospedali Riuniti di Bergamo in Italy, and lead author and presenter of the study, said.
For patients with low-risk PV, phlebotomy is the standard-of-care cytoreductive approach to treat blood hyperviscosity and reduce the risk of cardiovascular complications. The purpose of this study was to determine if a cytoreductive agent could provide additional efficacy.
The phase 2 Low-PV trial randomly assigned 100 patients with low-risk PV, defined as younger than 60 years and no history of thrombosis, to receive ropeginterferon added to phlebotomy and aspirin or stringent monthly phlebotomy with aspirin alone with a follow-up of 1 year. The primary endpoint was a composite of the proportion of patients who maintained a hematocrit (HCT) 45% or less with no progressive disease for 1 year. Secondary endpoints included number of phlebotomies, splenomegaly, leukocyte count, platelet count, and symptoms.
Baseline characteristics were similar between arms.
At the preplanned interim analysis, the steering committee and DSMB recommended against further enrollment due to overwhelming efficacy of ropeginterferon.
Significantly more patients achieved the composite endpoint in the ropeginterferon arm at 84% compared with 60% of patients in the standard of care arm (odds ratio [OR], 3.5; 95% CI, 1.3-10.4; P =.008). The HCT target was maintained by more patients who received ropeginterferon compared with those who received standard of care (84% vs 66%; P =.038).
Patients in the ropeginterferon arm required fewer phlebotomies at 1 year at 43% compared with 57% of patients in the standard-of-care arm, which was most pronounced 6 months after the start of ropeginterferon. There was also an improvement in symptoms, splenomegaly, leukocyte count, and platelet count.
The rate of grade 3 or higher adverse events was similar between arms, at 6% and 8% of patients in the ropeginterferon or standard-of-care arms, respectively.
Dr Barbui said “this interim analysis has fully demonstrated that ropeginterferon in low-risk PV patients is more efficacious in keeping the HCT at target levels in comparison to a strict and rigorous therapeutic phlebotomy policy.”
Read more of Cancer Therapy Advisor‘s coverage of the EHA virtual meeting by visiting the conference page.
Barbui T, Vannucchi AM, De Stefano V, et al. Phase II randomized clinical trial comparing ropeginterferon versus phlebotomy in low-risk patients with polycythemia vera. Results of the pre-planned interim analysis. Paper Presented at: Virtual Edition of the 25th European Hematology Association (EHA) Annual Congress; June 2020. Abstract LBA2602.