S291: PHASE I/II STUDY OF RILZABRUTINIB, AN ORAL BRUTON TYROSINE KINASE INHIBITOR, IN PATIENTS WITH IMMUNE THROMBOCYTOPENIA: LONG-TERM FOLLOW-UP. (23rd June 2022) - Kuter, D. J.; Efraim, M.; Kaplan, Z.; Mayer, J.; Choi, P.; Jansen, A. G.; McDonald, V.; Baker, R.; Bird, R.; Garg, M.; Gumulec, J.; Kostal, M.; et al.