OBJECTIVES: For decades, hydroxyurea was the only FDA-approved disease-modifying treatment (DMT) for sickle cell disease (SCD). Endari (L-glutamine, approved in 07/2017), Adakveo (crizanlizumab-tmca, approved in 11/2019), and Oxbryta (voxelotor, approved in 11/2019) are newly approved DMTs. This study aimed to describe the prescribing trends of all available DMTs for SCD treatment.

METHODS: This retrospective study used the 2016-2021 Meartive™ MarketScan Commercial Database. Subjects were included if they had ≥1 inpatient or ≥2 outpatient visits on separate dates with an SCD diagnosis and pharmacy coverage during the study period. Patients with a cancer diagnosis were excluded. The eligible ages for hydroxyurea, Endari, Adakveo, and Oxbryta were 2-64, 5-64, 16-64, and 12-64 years, respectively. The monthly dispensing rate for each medication was calculated by dividing the number of patients who had at least one prescription each month by the number of monthly enrollees who met the inclusion criteria and the eligible age limits.

RESULTS: The included subjects for hydroxyurea, Endari, Adakveo, and Oxbryta were 12,378 (mean [SD] age=29.5[16.4], 59.3% female), 11,879 (mean age=30.7[15.7], 59.6% female), 9,819 (mean age=35.4[13.1], 61.9% female), and 10,611 (mean age=33.6[14.0], 60.9% female), respectively. During the study period, 3,051, 221, 101, and 196 patients filled ≥1 prescription for each medication in the order listed above. Monthly dispensing rates in December 2021 were 10.81%, 0.46%, 0.78%, 1.94%, and 13.24%, respectively. Endari dispensing rates increased slightly after approval but declined a bit after the newer medications became available; Adakveo dispensing rates remained stable after a slight increase following approval; and Oxbryta dispensing rates have gradually increased since approval. The dispensing rate for hydroxyurea remains stable from 2016 to 2021, with a 1-2% fluctuation.

CONCLUSIONS: Between 2016 and 2021, the dispensing rates for DMTs increased slightly, especially after the approval of Adakveo and Oxbryta. However, the overall dispensing rates of newly approved DMTs remained low.