Ticagrelor reversal agent receives FDA breakthrough therapy designation

The FDA has granted a breakthrough therapy designation to a novel reversal agent for ticagrelor called PB2452, PhaseBio Pharmaceuticals announced April 8.

There are currently no FDA-approved reversal agents for P2Y12 inhibitors like ticagrelor, which are commonly used as part of dual antiplatelet therapy following acute coronary syndrome or percutaneous coronary intervention. Because all P2Y12 inhibitors increase bleeding risk, there’s a need for such antidotes.

But, as the authors of a recent phase I clinical study of the therapy pointed out, ticagrelor is a “reversible inhibitor” whereas prasugrel and clopidogrel are not.

Those researchers found that volunteers in the trial who were given PB2452 had a significantly greater increase in platelet function than those administered placebo. Ticagrelor reversal occurred within five minutes and was sustained for more than 20 hours, according to the results of the 64-patient study.

The breakthrough therapy designation allows PB2452 to be placed on a faster track to approval because “preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies,” according to PhaseBio’s press release.

“Breakthrough Therapy designation for PB2452 highlights the critical unmet need for a therapy to reverse the antiplatelet activity of ticagrelor, which is widely prescribed to patients with acute coronary syndrome or a history of heart attack,” John Lee, MD, chief medical officer of PhaseBio, said in the release. “The results from the Phase 1 clinical trial of PB2452 demonstrated immediate and sustained reversal of the antiplatelet activity of ticagrelor, which could mitigate bleeding concerns associated with use of ticagrelor.

“Breakthrough Therapy designation supports our goal of making the first approved reversal agent for ticagrelor available to patients and physicians as soon as possible.”

In May 2018, the FDA approved the use of andexanet alfa (Andexxa), the first reversal agent for Factor Xa inhibitors. That drug had also been given breakthrough therapy status.