PharmaEssentia is looking to expand the reach of its FDA-approved rare blood cancer treatment Besremi to another rare blood disorder after reviewing encouraging results from a phase 3 study.
In the SURPASS-ET trial, the company weighed its treatment, dubbed P1101 in the study, against platelet-reducing anagrelide as a second-line therapy for patients with essential thrombocythemia (ET).
Treatment with PharmaEssentia's medicine was associated with durable clinical responses, as measured by modified European Leukemia Net criteria, the company reported on Jan. 6. Of patients who used the treatment, 42.9% experienced durable responses at months 9 and 12. That compared with 6% who achieved the same result in the anagrelide arm.
The secondary endpoint, which looked at reductions in JAK2 V617F allelic burden, was also met, according to the company. This suggested that Besremi may have a greater effect on underlying disease pathology than the comparator drug, the company explained.
ET is a rare blood cancer typically caused by genetic mutations that cause bone marrow to produce too many platelets. Those with the disease are at a greater risk of suffering from heart attack or stroke due to obstructed blood flow, according to 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,” PharmaEssentia’s founder and CEO, Ko-Chung Lin, Ph.D., said in the company’s release. “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.”
The Taiwan-based drugmaker plans to submit the data to the FDA and other regulatory agencies “as soon as possible,” chief medical officer Albert Qin, M.D., Ph.D. added. Detailed clinical trial results will be presented at a later date and regulatory filings are expected by the end of 2025.
A follow-on ET indication would add a patient population of about 148,000 in the U.S. Currently, Besremi is approved to treat polycythemia vera, a rare blood cancer that causes a thickening of the blood, affecting some 6,200 people each year in the U.S.
Upon its 2021 FDA approval, Besremi became the first polycythemia vera treatment that patients can take regardless of their treatment history, as well as the first interferon drug approved for the disorder. The drug has so far been approved in more than 40 countries and comes with a boxed warning for the risk of serious effects including aggravation of neuropsychiatric, autoimmune, ischemic and infectious disorders.