Rigel Pharma Announces Results From Second FIT Phase 3 Study - Quick Facts

(RTTNews) - Rigel Pharmaceuticals, Inc. (RIGL) announced results for the second of two double-blind studies in the FIT Phase 3 clinical program for fostamatinib, an oral spleen tyrosine kinase or SYK inhibitor, in adult chronic/persistent immune thrombocytopenia (ITP).

The primary endpoint in the study was a stable platelet response, defined as platelet counts greater than 50,000/uL of blood on at least four of the last six scheduled clinic visits between weeks 14 and 24 of treatment.

In the FIT 2 (Study 048) Phase 3 study, the fostamatinib response rate was 18 percent, consistent with the recently reported FIT 1 (Study 047) Phase 3 study.

In Study 048, one patient in the placebo group (4%) achieved a stable platelet response. Therefore the difference between those on treatment and those on placebo did not reach statistical significance and the study did not meet its primary endpoint.

However, when the data from both studies are combined, this difference is statistically significant. According to Rigel Pharma, data from both FIT Phase 3 studies and the open-label extension study demonstrates the consistent benefit of fostamatinib in ITP.

"We believe that the totality and consistency of data from the FIT Phase 3 program, which included two Phase 3 studies and one long-term extension study, strongly supports a clear treatment effect, with a sustained clinical benefit of fostamatinib," said Raul Rodriguez, president and chief executive officer of Rigel.