CORRECTING and REPLACING PharmaEssentia Announces Positive Topline Phase 3 Data from SURPASS-ET Study Evaluating Ropeginterferon Alfa-2b-njft (P1101) for Essential Thrombocythemia

SURPASS-ET trial achieved its primary endpoint, demonstrating a durable response in 42.9% of participants in the P1101 group versus 6.0% in the comparator group (p=0.0001)

Data support our plan to submit for regulatory label expansion for ropeginterferon alfa-2b-njft

BURLINGTON, Mass.--(BUSINESS WIRE)--Please replace the release dated January 6, 2025, with the following corrected version due to multiple revisions.

The updated release reads:

PHARMAESSENTIA ANNOUNCES POSITIVE TOPLINE PHASE 3 DATA FROM SURPASS-ET STUDY EVALUATING ROPEGINTERFERON ALFA-2B-NJFT (P1101) FOR ESSENTIAL THROMBOCYTHEMIA

SURPASS-ET trial achieved its primary endpoint, demonstrating a durable response in 42.9% of participants in the P1101 group versus 6.0% in the comparator group (p=0.0001)

Data support our plan to submit for regulatory label expansion for ropeginterferon alfa-2b-njft

PharmaEssentia Corporation (TWSE: 6446), a global biopharmaceutical innovator based in Taiwan leveraging deep expertise and proven scientific principles to deliver new biologics in hematology and oncology, today announced positive topline results from its SURPASS-ET clinical trial of ropeginterferon alfa-2b-njft (P1101) in patients with essential thrombocythemia (ET). The trial achieved its primary endpoint, showing durable hematologic responses in patients treated with P1101 with a manageable safety profile and a lower rate of treatment-related serious adverse events (TRSAEs).

Ropeginterferon alfa-2b-njft is currently FDA approved and marketed as BESREMi® and indicated for polycythemia vera (PV). The Company plans to seek a label expansion to include ET.

SURPASS-ET Clinical Results

Clinical Trial Overview

SURPASS-ET (NCT04285086) is a global Phase 3, randomized, open-label, active-controlled clinical trial evaluating the efficacy, safety and tolerability of P1101 versus anagrelide as a second-line therapy for ET for 12 months. A total of 174 patients were enrolled, with 91 randomly assigned to the P1101 treatment group and 83 to the anagrelide group.

Primary Endpoint

• The trial successfully met its primary endpoint, demonstrating durable clinical response as measured using modified European Leukemia Net (ELN) criteria. Among the intent-to-treat (ITT) population, 42.9% (39/91) of participants in the P1101 group achieved durable responses at months 9 and 12, compared to 6.0% (5/83) in the comparator arm (administered anagrelide) (p=0.0001). P1101 exhibited a manageable safety profile and a lower rate of TRSAEs. In the P1101 arm, two TRSAEs were observed (2.2%) as compared to 8 (10%) in the anagrelide arm.

Secondary Endpoint:

• The JAK2 V617F allelic burden decreased from 33.7% at baseline to 25.3% (-8.4% change) at 12 months in the P1101 group, compared to a reduction from 39.7% to 37.3% (-2.4% change) in the anagrelide group. These results suggest that P1101 may have a greater impact on addressing the underlying disease pathology compared to anagrelide.

“We are extremely proud of the SURPASS-ET Phase 3 study outcome, which shows the potential of P1101 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, Ph.D., Founder and CEO of PharmaEssentia. “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.”

PharmaEssentia plans to present detailed clinical trial results, including additional pharmacokinetics and biomarker data, at a later date. The Company also intends to pursue regulatory discussions with the FDA to expand the existing label for P1101 to include a new potential indication of ET and anticipates regulatory submission by the end of 2025.

“The results of the SURPASS-ET trial are significant,” said Albert Qin, M.D., Ph.D., Chief Medical Officer. “ET is a challenging condition associated with symptoms and risks of thrombosis and disease progression. These encouraging results highlight the potential of P1101 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.”

The Company is also evaluating P1101 in ET patients in its EXCEED-ET (NCT05482971) clinical trial in North America. This Phase 2b clinical trial is a single-arm, multicenter trial designed to assess the efficacy, safety, and tolerability of P1101 in adult patients with ET. The company expects to present data from this clinical trial in the second half of 2025.

About Essential Thrombocythemia

Essential thrombocythemia is a chronic, rare blood disorder that is the most common type of myeloproliferative neoplasm. Essential thrombocythemia is most often caused by genetic mutations that cause the bone marrow to produce too many platelets, which can obstruct blood flow and cause a stroke, heart attack or pulmonary embolism.

It is estimated that approximately 148,000 people in the U.S. have ET, which can significantly impact quality of life due to burdensome symptoms. Patients diagnosed with ET face limited treatment options to manage their condition, particularly in reducing the risk of thrombosis and slowing disease progression.

About BESREMi® (ropeginterferon alfa-2b-njft) in polycythemia vera (PV)

BESREMi is an innovative monopegylated, long-acting interferon with marketing authorization in PV. With its unique pegylation technology, BESREMi has a long duration of activity in the body and is aimed to be administered once every two weeks (or every four weeks with hematological stability for at least one year), allowing flexible dosing that helps meet the individual needs of patients.

BESREMi has been approved in more than 40 countries, with approval from the European Medicines Agency (EMA) in 2019, by the US Food and Drug Administration (FDA) in 2021, and by the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan in 2023. It was invented by PharmaEssentia and is manufactured in the company’s Taichung plant, which was cGMP certified by TFDA in 2017 and by EMA in January 2018. PharmaEssentia retains full global intellectual property rights for the product in all indications.

BESREMi was approved with a boxed warning for risk of serious disorders including aggravation of neuropsychiatric, autoimmune, ischemic and infectious disorders.

Please see full Prescribing Information, including Boxed Warning.

About PharmaEssentia

PharmaEssentia (TWSE: 6446), headquartered in Taipei, Taiwan, is a global and rapidly growing biopharmaceutical innovator. Leveraging deep expertise and proven scientific principles, PharmaEssentia aims to deliver effective new biologics for challenging diseases in the areas of hematology, oncology, and immunology with one approved product and a diversifying pipeline. Founded in 2003 by a team of Taiwanese-American executives and renowned scientists from U.S. biotechnology and pharmaceutical companies, today PharmaEssentia is expanding its global presence with operations in the U.S., Japan, China, and Korea, along with a world-class biologics production facility in Taichung, Taiwan.

For more information about PharmaEssentia USA, visit the website, LinkedIn or X (formerly Twitter).