Ibrutinib Plus Venetoclax In Patients With Relapsed/Refractory Mantle Cell Lymphoma: Results From The Safety Run-In Period Of The Phase 3 Sympatico Study

Background: Ibrutinib (ibr) is a once-daily Bruton’s tyrosine kinase (BTK) inhibitor approved in the US for patients (pts) with mantle cell lymphoma (MCL) who have received ≥1 prior therapy. Venetoclax (ven) is a BCL-2 inhibitor approved for pts with CLL or previously untreated AML. Ibr + ven have shown synergistic antitumor activity in preclinical models and complementary clinical activity in early phase studies (Zhao Br J Haematol 2015; Tam NEJM 2018; Jain NEJM 2019). The ongoing phase 3 SYMPATICO study (PCYC-1143-CA, NCT03112174) evaluates the safety and efficacy of ibr + ven in pts with relapsed/refractory (R/R) MCL. A safety run-in (SRI) was conducted to inform whether a 1-month (mo) ibr lead-in would be implemented for the randomized portion of the study; initial data from the SRI evaluating tumor lysis syndrome (TLS) events and dose-limiting toxicities (DLTs) concluded that the study would proceed with concurrent ibr + ven, with no ibr lead-in (Wang ICML 2019). Updated safety and efficacy from the SRI are presented.