Acquired Resistance to BRAF Inhibition in Hcl Is Rare and Retreatment with Vemurafenib at Relapse Can Induce High Response Rates: Final Results of a Phase II Trial of Vemurafenib in Relapsed Hcl

Conclusion: With a longer follow-up duration of up to 64 months, we confirm the high response rates with vemurafenib monotherapy in pts with R/R HCL and a favorable safety profile. While relapses were common, all cases of relapse retained BRAF V600E mutation and acquired resistance to vemurafenib was rare, observed in only 1 pt with KRAS mutation. Re-treatment with vemurafenib at relapse was highly effective with 85% ORR confirming the retained high sensitivity of HCL to repeated BRAF inhibition. Based on the high anti-tumor efficacy and tolerability of BRAF inhibition with vemurafenib, we are now investigating the combination of vemurafenib and an anti-CD20 antibody, obinutuzumab, as a frontline therapy in a phase II trial in pts with previously untreated HCL (NCT03410875).Figure.DisclosuresPark: AstraZeneca: Consultancy; Juno Therapeutics: Consultancy, Research Funding; Pfizer: Consultancy; Shire: Consultancy; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Consultancy; Novartis: Consultancy; Adaptive Biotechnologies: Consultancy. Altman: Bayer: Other: payment to the institution to conduct clinical trial work; Boeringer Ingelheim: Other: payment to the institution to conduct clinical trial work; Epizyme: Other: payment to the institution to conduct clinical trial work; Incyte: Other: payment to the institution to conduct clinical trial work; Cyclacel: Other: payment to the institution to conduct clinical trial work; Syro...
Source: Blood - Category: Hematology Authors: Tags: 623. Mantle Cell, Follicular, and Other Indolent B-Cell Lymphoma-Clinical Studies: Novel Therapies and Prognostic Assessment in Hairy Cell Leukemia and Indolent Non-Hodgkin Lymphoma Source Type: research