Daratumumab Split First Versus Single Dosing Schedule Among Patients With Multiple Myeloma Treated in a US Community Oncology Setting: A Retrospective Observational Study

Abstract

Purpose: Daratumumab was initially approved by the US Food and Drug Administration to be given intravenously over the course of several hours during each administration. Because the duration of the first dose can exceed 7 h, the US Oncology Network developed a split first dose schedule to administer the first administration (dose) over 2 consecutive days.

Methods: This trial was a retrospective cohort study of adult multiple myeloma (MM) patients who initiated daratumumab within the US Oncology Network between November 1, 2015, and June 30, 2017. Descriptive analyses were conducted to compare split dose versus single-dose groups, and a multivariable linear regression model was developed to identify factors associated with total administration time.

Findings: In total, 622 patients were included in the analysis (364 split first dose patients and 258 single-dose patients). Infusion reactions to the first administration were documented for 47.8% of split first dose patients and 48.3% of single-dose patients. Among the total study population, the most common reactions were lower respiratory tract-related reactions (26.1%), upper respiratory tract-related reactions (17.2%), and gastrointestinal adverse events (12.5%), with no statistically significant differences between groups. The median infusion duration was 4.5 h for day 1 of the split first dose and 6.5 h for the single dose (P < 0.0001); the total median infusion time was 8.7 h for the split first dose. In multivariable regression, the only factor associated with infusion time was dosing schedule.

Implications: These results provide real-world evidence regarding the safety and infusion time of the first infusion of daratumumab. Although the total administration time was longer among patients receiving a split first dose, the shorter day 1 infusion for this dosing schedule without increased infusion reactions may be an option for community oncology clinics.

Keywords: community oncology; electronic healthcare records; monoclonal antibody; myeloma and other plasma cell dyscrasias; retrospective observational research.