Curis announces clinical data from TakeAim Leukemia Study of emavusertib

Curis announced positive updated clinical data from the ongoing open label Phase 1a dose escalation study of emavusertib, a novel, small molecule IRAK-4 inhibitor, as a monotherapy in patients with relapsed or refractory acute myeloid leukemia or high risk myelodysplastic syndromes (hrMDS) in both targeted and non-targeted populations. Patients in a targeted population are those with disease harboring U2AF1, SF3B1 or FLT3 mutations. The company also announced positive initial data of emavusertib in combination with venetoclax in patients with AML or hrMDS that enrolled in the combination phase of the TakeAim Leukemia study prior to the partial clinical hold placed in April 2022. As of October 12, 2022, the total monotherapy data to date represents 24 response evaluable patients with a targeted mutation and 34 response evaluable patients without a targeted mutation. This represents 11 additional patients treated in targeted monotherapy populations and 13 additional patients in the non-targeted monotherapy population. In addition to the monotherapy data, there are 4 patients with AML/hrMDS who have been treated with emavusertib in combination with venetoclax. In Expanded Data Set, Findings Support Earlier Data Presented in June 2021 and January 2022 Previous data presented by Curis highlighted preliminary efficacy data of emavusertib in R/R AML/MDS patients whose disease is characterized by spliceosome or FLT3 mutation. It is this genetically-defined subset of AML/MDS that is specifically targeted by emavusertib and which we believe, represents the patients most likely to benefit from treatment with emavusertib in monotherapy. Today’s clinical data update provides an expanded data set for this genetically-defined patient population. In targeted AML patient monotherapy populations key findings included: Patients with a FLT3 mutation had a CR rate of 29%; In addition to the 2 patients who achieved CRs, a 3rd patient achieved MLFS, and a 4th patient with gilteritinib-refractory disease achieved near normalization of blast count and complete loss of detectable FLT3 clone Patients with a spliceosome mutation had CR/CRh rate of 22%. In targeted hrMDS patient monotherapy populations key findings included: ORR of 45%. All 5 responses achieved a marrow CR. In combination AML/hrMDS patient populations key findings included: ORR of 50%. Both responses achieved mCR. These data continue to confirm the earlier data that emavusertib provides favorable anti-cancer activity in AML and hrMDS patients with a spliceosome and/or FLT3 mutation. Further, anti-cancer activity in non-targeted patients as well as in combination with venetoclax suggest potential for incremental efficacy in combination with existing therapies. We are continuing to enroll patients at the 200mg dose level and plan to discuss with the U.S. Food and Drug Administration a recommended phase 2 dose in mid-2023.