1st patient dosed in Phase 2b trial of SerpinPC for Hem B with inhibitors
SerpinPC being developed for hemophilia, regardless of severity, inhibitor status
The first participant has been dosed in a Phase 2b clinical trial that’s assessing the safety and efficacy of SerpinPC in people with hemophilia B who have inhibitors, according to an announcement from its developer, Centessa Pharmaceuticals.
“We are excited to be further evaluating the potential of SerpinPC’s novel mechanism of action in individuals living with hemophilia B with inhibitors, where there are limited treatment options,” Antoine Yver, MD, chairman of development at Centessa, said in a company press release.
SerpinPC is designed to promote blood clotting by blocking the activity of activated protein C, which normally works to lessen blood clotting. Centessa is developing SerpinPC as a potential treatment for hemophilia regardless of severity or inhibitor status.
PRESent-3 trial to enroll 12 hemophilia B patients with inhibitors
The Phase 2b trial, called PRESent-3 (NCT05789537), is expected to enroll about 12 people with hemophilia B who have inhibitors, which are antibodies that bind to clotting factors provided by replacement therapies, potentially reducing the effectiveness of these standard hemophilia treatments. The study is open to male patients ages 12 to 65, and enrollment is ongoing at sites in Armenia and Taiwan.
Participants in the trial will first undergo 12 weeks of monitoring while on their current therapies. This monitoring period can also be completed through a parallel observational study called PRESent-5 (NCT05605678), which is enrolling people with hemophilia types A and B at sites worldwide.
After initial monitoring, all participants in the PRESent-3 trial will receive treatment with SerpinPC for about a year. The treatment will be given by a subcutaneous (under-the-skin) injection every other week at a dose of 1.2 milligrams per kilogram of body weight.
The trial’s main goal is to evaluate the effect of treatment on the rates of bleeds after 24 weeks, or about six months.
The start of dosing in this Phase 2 study comes a few months after Centessa announced the beginning of dosing in another Phase 2 trial testing SerpinPC, called PRESent-2 (NCT05789524). That study is open to patients ages 12 to 65 who have moderate to severe hemophilia B without inhibitors, or severe hemophilia A with or without inhibitors.
Participants in PRESent-2 will be given SerpinPC injections at varying dosing schedules, ranging from once weekly to once every four weeks. Like in the PRESent-3 study, participants must first undergo 12 weeks of monitoring, and the study’s main goal is to assess the effect of treatment on the rates of bleeds after about six months. Participants are currently being recruited at sites in Armenia, Taiwan, and South Africa.
SerpinPC was granted fast track designation by the U.S. Food and Drug Administration earlier this year, which is designed to speed the development of potentially important therapies. The agency also granted SerpinPC orphan drug status, a designation that seeks to incentivize the development of treatments for rare diseases.