{"entity":{"id":"idelalisib","kind":"drug","name":"Idelalisib","aka":[],"tldr":"Idelalisib was the first PI3K inhibitor for blood cancers; it is effective in CLL with rituximab but so toxic (colitis, hepatitis, pneumonitis, infections) that the class has largely been abandoned.","summary":"Approved 2014 (CLL with rituximab; FL and SLL accelerated). Trials in earlier lines were halted in 2016 over fatal infections and toxicity; the FL/SLL indications were withdrawn in 2022. Remains an option in relapsed CLL after BTK and BCL2 inhibitors. Its history shaped FDA scepticism of PI3K inhibitors (2022 ODAC).","status":"approved","asOf":"2026-09-08","wikipedia":"https://en.wikipedia.org/wiki/Idelalisib","links":[{"label":"Label (DailyMed)","url":"https://dailymed.nlm.nih.gov/dailymed/search.cfm?labeltype=all&query=idelalisib"}],"tags":["gap-fill"],"related":[],"cancers":["cll","follicular-lymphoma","cll-relapsed"],"sections":[],"technologies":["kinase-inhibitors"],"targets":["pik3ca"],"drugs":[],"companies":["gilead"],"institutions":[],"pathways":["pi3k-akt-mtor"],"terms":[],"trials":["nct06846671","nct02970318"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"brand":"Zydelig","modality":"Small-molecule PI3Kδ inhibitor","mechanism":"Selective inhibition of the delta isoform of PI3K, blocking B-cell receptor-driven survival signalling in malignant B cells.","approvals":[{"region":"US","year":2014,"indication":"Relapsed CLL with rituximab; relapsed FL and SLL (accelerated, withdrawn 2022)"},{"region":"EU","year":2014,"indication":"CLL, FL"}],"mechanismSteps":[],"toxicity":[],"access":[],"regulatoryEvents":[{"date":"2014-07-23","type":"accelerated-approval","region":"US","note":"Accelerated approval on a surrogate endpoint, with a confirmatory trial required.","indication":"For the treatment of relapsed follicular B-cell Non-Hodgkin Lymphoma (FL) in patients who have received at least 2 prior systemic therapies and relapsed small lymphocytic lymphoma (SLL) in patients who have received at least 2 prior systemic therapies"},{"date":"2022-02-18","type":"withdrawal","region":"US","note":"Withdrawn: the indication came off the label 7.6 years after its accelerated approval.","indication":"For the treatment of relapsed follicular B-cell Non-Hodgkin Lymphoma (FL) in patients who have received at least 2 prior systemic therapies and relapsed small lymphocytic lymphoma (SLL) in patients who have received at least 2 prior systemic therapies"}]},"route":"/drugs/idelalisib/","neighbours":{"cancer":[{"id":"cll","kind":"cancer","name":"Chronic lymphocytic leukaemia","route":"/cancers/cll/"},{"id":"follicular-lymphoma","kind":"cancer","name":"Follicular lymphoma","route":"/cancers/follicular-lymphoma/"},{"id":"cll-relapsed","kind":"cancer","name":"Relapsed or refractory chronic lymphocytic leukaemia","route":"/cancers/cll-relapsed/"}],"technology":[{"id":"kinase-inhibitors","kind":"technology","name":"Small-molecule kinase inhibitors","route":"/technologies/kinase-inhibitors/"}],"target":[{"id":"pik3cd","kind":"target","name":"PI3K delta (PIK3CD)","route":"/targets/pik3cd/"},{"id":"pik3ca","kind":"target","name":"PIK3CA / PI3K-alpha","route":"/targets/pik3ca/"}],"company":[{"id":"gilead","kind":"company","name":"Gilead Sciences (incl. Kite)","route":"/companies/gilead/"}],"pathway":[{"id":"pi3k-akt-mtor","kind":"pathway","name":"PI3K / AKT / mTOR","route":"/pathways/pi3k-akt-mtor/"}],"trial":[{"id":"nct02970318","kind":"trial","name":"A Study of Acalabrutinib vs Investigator's Choice of Idelalisib Plus Rituximab or Bendamustine Plus Rituximab in R/R CLL","route":"/trials/nct02970318/"},{"id":"nct06846671","kind":"trial","name":"A Study of Tacabrutideg (BGB-16673) Compared to Investigator's Choice in Participants With Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma Previously Exposed to Both Bruton Tyrosine Kinase (BTK) and B-cell Leukemia/Lymphoma 2 Protein (BCL2) Inhibitors","route":"/trials/nct06846671/"},{"id":"nct05725200","kind":"trial","name":"Study to Investigate Outcome of Individualized Treatment in Patients With Metastatic Colorectal Cancer","route":"/trials/nct05725200/"}],"term":[{"id":"approval-withdrawal","kind":"term","name":"Indication withdrawal","route":"/terms/approval-withdrawal/"},{"id":"lymphoma-tx-pjp-and-infection-prophylaxis","kind":"term","name":"Infection prophylaxis in lymphoma: PJP, herpes, fungal risk and vaccination","route":"/terms/lymphoma-tx-pjp-and-infection-prophylaxis/"}]}}