FDA Approves First BTK Inhibitor for ITP

The U.S. Food and Drug Administration (FDA) has approved Sanofi’s Wayrilz (rilzabrutinib) for adults with persistent or chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment. Approval was based on the pivotal LUNA 3 Phase III study in which Wayrilz met the primary and secondary endpoints, showing a positive impact on sustained platelet counts and other ITP symptoms. As a novel oral, reversible, Bruton’s tyrosine kinase (BTK) inhibitor, Wayrilz can help address the root causes of ITP through multi-immune modulation, targeting different pathways across the immune system.

In the study, researchers evaluated the efficacy and safety of Wayrilz compared to placebo in adults (n=202) with persistent or chronic ITP. Patients who achieved platelet count response at 12 weeks were eligible to continue the full 24-week double-blind period (64 percent of patients in the Wayrilz arm and 32 percent of patients in the placebo arm). Patients receiving Wayrilz experienced the following compared to patients receiving placebo:

• Statistically significant durable platelet response at week 25 (23 percent of patients in Wayrilz arm vs. 0 percent in placebo arm; p<0.0001)

• Faster time to first platelet response (36 days in Wayrilz arm vs. not reached in placebo arm; p<0.0001)

• Longer duration of platelet response (least square mean of seven weeks in Wayrilz arm vs. 0.7 weeks in placebo arm)

Patients receiving Wayrilz reported an overall 10.6-point improvement across nine health-related quality of life measures compared to a 2.3-point increase in the placebo arm, based on the Immune Thrombocytopenia Patient Assessment Questionnaire, a clinical tool designed to measure ITP symptoms. The most common adverse reactions (incidence ≥10 percent) are diarrhea, nausea, headache, abdominal pain and COVID-19.

“Traditionally, [ITP] management has focused on restoring platelet counts and reducing bleeding risk, which for some patients may result in suboptimal responses, persistent symptoms or unacceptable treatment complications,” said David Kuter, MD, director of clinical hematology at Massachusetts General Hospital, professor of medicine at Harvard Medical School and the study’s author. “Through multi-immune modulation, Wayrilz can offer a new option for patients, including those who fail steroids or do not respond to existing treatment.”