Idelalisib Post Allogeneic Hematopoietic Stem Cell Transplant (HSCT) in B Cell Derived Malignancies

This is a study to evaluate the safety of idelalisib as post-transplantation maintenance in patients with B cell hematologic malignancies undergoing a allogeneic hematopoietic stem cell transplant (HSCT). Safety will be evaluated through the assessment of cytopenias, effect on donor chimerism, effect on the incidence and severity of acute graft versus host disease, and gastro-intestinal tolerance.

Currently, to improve overall survival, the focus of the BMT program at JHH the introduction of anti-neoplastic therapy post transplantation: where the allo BMT serves as a platform to allowing a new intolerant immune system to interact with the post allo BMT intervention. The importance of post BMT therapy has been made evident with tyrosine kinase inhibition (TKI) in Philadelphia chromosome positive acute lymphocytic leukemia (ALL) and chronic myeloid leukemia(CML), where patients who had disease progression while on TKI therapy pre-allo BMT enjoy marked improvement in overall survival when TKI is part of a maintenance program; the use of DNA hypomethylation agents after allo BMT for relapsed myeloid malignances; or the use of rituximab after allo BMT in follicular lymphoma. Idelalisib, an orally-administered, selective inhibitor of Phosphoinositide 3 kinase (PI3K), is extremely effective in inducing partial responses to complete responses in many B-cell derived malignancies and should be studied in the post alloHSCT setting. Johns Hopkins Hospital has one of the world's largest experiences with alloHSCT. This study proposes a double blinded randomized phase I placebo trial where all patients who have undergone alloHSCT for a B-cell derived hematologic malignancy be offered either idelalisib 100mg or placebo twice daily for 180 days starting approximately 90 days after their HSCT.