CALR-1 Mutation Is an Important Survival Predictor in Momelotinib-Treated Patients With Myelofibrosis

CALR-1 mutation is an important risk factor for both drug survival and longevity without allogeneic hematopoietic stem cell transplant (HSCT) in momelotinib-treated patients with myelofibrosis (MF), according to a study presented at the 65th ASH Annual Meeting & Exposition.

Ayalew Tefferi, MD, and colleagues analyzed 79 Janus kinase 2 inhibitor-naïve patients with MF (median age, 67 years; 54% men). They calculated drug survival from time of initiation of momelotinib to time of treatment discontinuation.

Multivariable analysis showed that the absence of CALR-1 mutation (hazard ratio [HR], 3.5; 95% CI, 1.2-10.5; P=.03) and the presence of high molecular risk (ASXL1/SRSF2) mutations (HR, 2.3; 95% CI, 1.1-4.6; P=02) were independent predictors of inferior survival. Overall, the findings showed that the absence of CALR-1 mutation (HR, 2.9; 95% CI, 1.02-8.1), age ≥63 years (HR, 3.0; 95% CI, 1.5-6.0), and the absence of spleen response (HR, 2.6; 95% CI, 1.5-4.5) were the most notable predictors of inferior transplant-censored survival.

“Such information might help identify MF patients who might benefit from treatment with momelotinib and in whom [allogeneic] HSCT might be deferred or not,” the researchers concluded.

Reference

Tefferi A, Pardanani A, Begna K, et al. Type 1/like Calr mutation in momelotinib-treated patients with myelofibrosis is the most prominent predictor of drug survival and longevity without transplant. Abstract #4555. Presented at the 65th ASH Annual Meeting & Exposition; December 9-12, 2023; San Diego, California.