Analysis of real-world (RW) pomalidomide (pom) dosing patterns in patients (pts) with multiple myeloma (MM) from the Flatiron database.

Abstract

e19508 Background: Pom is an immunomodulatory drug commonly used in combination with other antimyeloma therapies for the treatment (tx) of pts with MM. However, there is a paucity of data on RW dosing patterns with pom and associated tx outcomes. We report RW pom dosing patterns and effectiveness using RW data to inform potential pom dosing strategies as part of combination tx regimens. Methods: RW pom data in pts with MM were derived from the US Flatiron Health deidentified electronic health record (EHR) database (Jan 2011–Nov 2021). Pom starting dose (1, 2, 3, or 4 mg) and line of therapy (LOT) were identified from EHRs. Tx patterns were captured per LOT; pts could receive >1 pom-containing tx regimen/LOT. Pts receiving pom were followed until Dec 2023 for outcome analysis. Overall survival (OS) and time to next tx (TTNT) were estimated using the Kaplan-Meier method and analyzed by log-rank testing. Results: Of 15,378 pts with MM, 2,034 had an order for pom, of whom 1,344 received pom and 880 had LOT data. The most common initial pom dose was 4 mg (50%), followed by 2 mg (30%), 3 mg (16%), and 1 mg (4%). The most common pom-containing tx regimens were: daratumumab + pom + dexamethasone (d; 29%), pom + d (18%), and carfilzomib + pom + d (14%); 6% of pts received pom monotherapy. Retreatment with pom was infrequent, with 84% of pts receiving only 1 pom-containing LOT. Most pts (n=652, 74%) remained on the initial pom dose received; of these, 367 pts remained on an initial dose of 4 mg. Among pts who changed dose (n=227, 26%), 36% changed from 2 mg and 36% changed from 4 mg. Of pts who received an initial dose of 4 mg and changed dose (n=81), 43%, 51%, and 6% reduced to 3, 2, and 1 mg, respectively. Of pts who received an initial dose of 2 mg and changed dose (n=82), 17% reduced to 1 mg. Among pts who received an initial dose of <4 mg and changed dose, dose escalation was common (67% of pts with a 3 mg initial dose increased to 4 mg; 33% and 50% of pts with a 2 mg initial dose increased to 3 and 4 mg, respectively). Outcome analysis of pts with LOT and available follow-up data suggest that initial pom dose had no impact on OS and TTNT (Table). Log-rank analysis of OS and TTNT between the initial doses of 2 and 4 mg showed no significant difference among all pts ( P=0.32) or in pts who changed dose ( P=0.29). Conclusions: RW analyses show that most pts remain on the initial pom dose received, but some pts changed doses. Pom, most commonly used in combination regimens, can be used across an initial dose range with no impact on efficacy in pts with MM. Optimal pom dosing may vary across pts and combination regimens; pom dosing should be tailored to pt needs per disease and tx factors. [Table: see text]