The SURPASS-ET trial (NCT04285086), evaluating ropeginterferon alfa-2b (Besremi) in patients with essential thrombocythemia (ET), has achieved its primary endpoint, demonstrating a durable clinical response as defined by modified European Leukemia Net (ELN) criteria.1
In the intent-to-treat (ITT) population, 42.9% (39/91) of patients treated with ropeginterferon alfa-2b had durable responses at 9 and 12 months vs 6.0% (5/83) of patients enrolled in the comparator arm who were treated with anagrelide (Agrylin) (P =.0001).
For the secondary end point, the JAK2 V617F allele burden decreased from 33.7% to 25.3% (-8.4%) in the ropeginterferon alfa-2b group over 12 months, compared with a reduction from 39.7% to 37.3% (-2.4%) in the anagrelide group. These findings indicate that ropeginterferon alfa-2b may provide a more pronounced effect on mitigating the underlying disease pathology relative to anagrelide.
“We are extremely proud of the SURPASS-ET phase 3 study outcome, which shows the potential of [ropeginterferon alfa-2b] as an important new treatment option for patients with ET, a rare blood cancer that drastically increases the risk of heart attack or stroke,” said Ko-Chung Lin, PhD, founder and chief executive officer of PharmaEssentia, in a press release. “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.”
For safety, ropeginterferon alfa-2b did not lead to any treatment-related serious adverse events. Overall, the agent had a manageable safety profile.
Full trial results, including additional pharmacokinetics and biomarker data, are expected to be presented at a later date.
“The results of the SURPASS-ET trial are significant,” said Albert Qin, MD, PhD, chief medical officer, PharmaEssentia, in a press release. “ET is a challenging condition associated with symptoms and risks of thrombosis and disease progression. These encouraging results highlight the potential of [ropeginterferon alfa-2b] to provide an effective and tolerable new treatment option that we believe could provide a substantial clinical benefit for patients with ET. We plan to submit these results to the FDA and other regulatory agencies as soon as possible in hopes of providing this potential new treatment option to patients with ET.”