Rigel Pharmaceuticals’ (NASDAQ:RIGL) fostamatinib disodium has experts questioning Phase II autoimmune haemolytic anaemia (AIHA) outcomes despite positive immune thrombocytopenia (ITP) read outs. Whilst fostamatinib’s platelet-raising action in ITP may bode well for a haemoglobin (Hgb) increase in AIHA, the lack of AIHA human data and AIHA versus ITP disease disparities clouds optimism.
Preclinical mice data in AIHA somewhat encouraged expert enthusiasm. AIHA’s treatment need may prompt Phase III progression even if Phase II response rates are disappointing, some added.
The 37-patient, two-stage Phase II study will enrol 17 patients in stage 1, with proof-of-concept data expected YE16, according to Rigel’s website. Stage 2 will enrol 20 patients after stage 1 completion. The overall trial is due for primary completion in August 2017, according to ClinicalTrials.gov.