Sanofi Reports Experimental Therapy for Blood Disorder Met Phase 3 Endpoint

Rare Daily Staff

Sanofi said its experimental therapy rilzabrutinib met its primary endpoint of durable platelet response in a phase 3 trial of adult patients with persistent or chronic immune thrombocytopenia, a rare, autoimmune blood disease.

LUNA 3 study found a higher proportion of patients receiving rilzabrutinib achieved the primary endpoint versus placebo. The result was achieved in a population of patients with primary ITP that had been refractory to prior therapy. Overall, study participants had a median of four prior ITP therapies and a median baseline platelet count of 15,000/μL (normal platelet count levels typically range from 150,000-450,000/μL).

Positive results on key secondary endpoints also underscore the potential for rilzabrutinib to deliver clinically meaningful benefits for patients living with persistent and chronic ITP.

Immune thrombocytopenia (ITP) is an acquired disorder characterized by autoantibody-mediated platelet destruction and impaired platelet production, leading to low platelet counts and an increased risk of life-threatening bleeding episodes. In addition, patients with ITP often experience significant quality-of-life impairments such as fatigue and cognitive dysfunction.

Rilzabrutinib is an oral, reversible, covalent BTK inhibitor that has the potential to be a first- or best-in-class treatment of several immune-mediated diseases. BTK, expressed in B cells, mast cells, and other cells from the innate immune system, plays a critical role in inflammatory pathways and multiple immune-mediated disease processes. Rilzabrutinib can selectively inhibit the BTK target and could address the underlying mechanisms responsible for a wide range of ITP complications. Rilzabrutinib was granted Fast Track designation by the U.S. Food and Drug Administration for the treatment of ITP in November 2020 and was previously granted Orphan Drug designation.

In addition to ITP, rilzabrutinib is being studied across a variety of immune-mediated diseases including asthma, chronic spontaneous urticaria, prurigo nodularis, IgG4-related disease and warm autoimmune hemolytic anemia.

Sanofi expects to make regulatory submissions in the United States and European Union by the end of the year.

“The results of this study reinforce rilzabrutinib’s potential to be a first-in-class oral, reversible BTK inhibitor that can provide clinically meaningful improvements for people living with severe immune-mediated diseases like ITP,” said Houman Ashrafian, executive vice president and head of research and development for Sanofi.

Photo: Houman Ashrafian, executive vice president and head of research and development for Sanofi