SURPASS-ET Topline Findings Support Broader Label for Ropeginterferon Alfa-2b

Ropeginterferon alfa-2b-njft (P1101) treatment has induced durable hematologic responses in patients with essential thrombocythemia (ET), meeting the primary endpoint of the phase 3 SURPASS-ET clinical trial. According to an announcement of topline results issued by the PharamaEssentia Corporation, these findings will support an application to expand the FDA label for ropeginterferon alfa-2b.

“The results show that the well-tolerated therapy, ropeginterferon alfa-2b, is compelling enough to be the new standard as second-line therapy for patients with essential thrombocythemia with expectations of improved count control and decrease in JAK2 allele burden.” Ruben A. Mesa, MD, FACP, told Blood Cancers Today. “This builds from the positive experience in the related disease of polycythemia vera where ropeginterferon alfa-2b became a standard of care and was FDA approved in 2021.” Dr. Mesa is the president of Atrium Health Levine Cancer, executive director of Atrium Health Wake Forest Baptist Comprehensive Cancer Center, enterprise senior vice president of Atrium Health, and vice dean for Cancer Programs, Wake Forest University School of Medicine.

SURPASS-ET compared second-line treatment with ropeginterferon alfa-2b with anagrelide in patients with ET over a 12-month period. Of the 174 patients enrolled, 91 were randomly assigned to the ropeginterferon alfa-2b arm, and 83 patients received anagrelide. Overall, 42.9% of patients in the ropeginterferon alfa-2b arm achieved durable response at months 9 and 12 compared with only 6.0% of those in the control arm (P =.0001). Moreover, a lower rate of  serious treatment-related adverse events were observed with the experimental agent (2.2%) vs the control (10%), underscoring the manageability of its safety profile.

Topline data also revealed that the study has shown a trend toward achieving its secondary endpoint of decreasing the JAK2 V617F allelic burden. In the study, JAK2 V617F allelic burden was assessed at baseline and at the 12-month mark. In comparison with the baseline assessment, patients treated with ropeginterferon alfa-2b showed an 8.4% decrease in JAK2 V617F allelic burden versus a 2.4% decrease in the anagrelide arm. Based on this finding, investigators believe that ropeginterferon alfa-2b may address underlying disease more effectively than anagrelide.

“The data highlight the broad potential to apply our innovative monopegylated, long-acting interferon technology as a significant step forward for treating ET, and potentially other myeloproliferative neoplasms, with non-chemotherapy treatments. We plan to leverage these data to expand the existing P1101 product label and further expand the reach of P1101 to address this growing global unmet medical need,” stated Ko-Chung Lin, PhD, founder and CEO of PharmaEssentia, in a press release.

Detailed findings from SURPASS-ET including pharmacokinetic and biomarker data will be presented in the future. PharmaEssentia Corporation is also investigating ropeginterferon alfa-2b in the ongoing phase 2b EXCEED-ET clinical trial (NCT05482971).

“As we have seen in PV, we think ropeginterferon alfa-2b will make a compelling case as superior in front- and second-line settings based on ability to both control elevated blood counts and decrease the allele burden,” explained Mesa and Charles L. Spurr, MD, Professor of Internal Medicine, Wake Forest University School of Medicine.

Reference

PharmaEssentia announces positive topline phase 3 data from SURPASS-ET study evaluating ropeginterferon alfa-2b-njft (P1101) for essential thrombocythemia. News release. PharmaEssentia Corporation. January 6, 2024. Accessed January 6, 2024.  https://bwnews.pr/4h0SmjQ