Oral SYK Inhibitor for ITP:
- Immune Thrombocytopenic Purpura (ITP) is an autoimmune disease where the immune system attacks and destroys platelets in the blood. The result - abnormally low platelet counts.
- There are two forms of ITP: acute thrombocytopenic purpura, which is most commonly seen in young children; and chronic thrombocytopenic purpura, which requires continual follow up care with a hematologist.
- There are approximately 60,000 to 125,000 patients with adult primary ITP in the U.S., and it qualifies as an orphan disease.
- Rigel is focusing its Fostamatinib ITP program on the chronic form of this disorder targeting the underlying autoimmune cause of the disease rather than stimulating platelet production.
- Antibodies, usually of the IgG type, mediate platelet destruction in ITP. Fostamatinib has a unique mechanism of action, blocking IgG receptor signaling in both macrophages and B cells via SYK kinase.
- Rigel completed and reported results from the FIT Phase 3 clinical program of fostamatinib in ITP in 2016.
- In June 2017, the U.S. Food and Drug Administration (FDA) accepted for filing the New Drug Application (NDA) for fostamatinib in patients with chronic or persistent immune thrombocytopenia (ITP).
- The FDA has set the date of April 17, 2018, to complete its review under the Prescription Drug User Fee Act (PDUFA).