PhaseBio announces first patient dosed in Phase 2b clinical trial of PB2452
PhaseBio Pharmaceuticals announced that the first patient has been dosed in a Phase 2b clinical trial of PB2452, a novel, recombinant, human monoclonal antibody antigen-binding fragment designed to reverse the antiplatelet activity of ticagrelor in major bleeding and urgent surgery situations. The Phase 2b multi-center, randomized, double-blind, placebo-controlled trial is designed to evaluate the safety and efficacy of PB2452 in reversing the antiplatelet effects of ticagrelor as part of a dual antiplatelet regimen including low-dose aspirin. Additionally, the Phase 2b trial marks the beginning of United States Food and Drug Administration- aligned registrational trials to support the submission of a Biologics License Application for potential accelerated approval of PB2452. Approximately 200 older and elderly subjects are expected to be enrolled, resembling the patient population most likely to be treated with ticagrelor and potentially benefit from PB2452, if approved. Subjects will be randomized in a ratio of 3:1 and will receive either PB2452 or placebo, with approximately 150 subjects receiving PB2452. The primary endpoint of the trial is reversal of the antiplatelet effects of ticagrelor with intravenous infusion of PB2452 or placebo, as measured by the VerifyNow PRUTest biomarker. PhaseBio recently completed a Phase 2a trial in which PB2452 achieved immediate and sustained reversal of the antiplatelet effects of ticagrelor in older and elderly subjects on dual antiplatelet therapy of ticagrelor and low-dose aspirin. PB2452 was generally well tolerated, with only minor adverse events reported. These results are consistent with the results observed in healthy younger subjects treated with ticagrelor in the previously published Phase 1 trial. Additionally, the Phase 2a trial investigated a PB2452 regimen for the reversal of supratherapeutic doses of ticagrelor in healthy younger subjects, which demonstrated immediate and sustained reversal of the antiplatelet effects of ticagrelor and was well tolerated, consistent with the earlier cohorts in the Phase 2a trial and the Phase 1 trial.