‘Fast but not so Furious’: Short observation time after subcutaneous Daratumumab administration is both a safe and cost-effective strategy

Subcutaneous daratumumab has less infusion related reactions (IRR) than the intravenous formulation, but requires post-injection observation. The study sought to demonstrate safety and costs benefits associated with differing observation periods of subcutaneous daratumumab. A total of 66 patients were included. Short post-injection observation was safe and resulted in reduced infusion chair time as well as administration related cost and resources. Daratumumab, an anti-CD38 monoclonal antibody, is a key component in the treatment paradigms of multiple myeloma and AL amyloidosis in both the newly diagnosed and relapsed and/or refractory setting. Intravenous (IV) daratumumab administration requires extended infusion times and is associated with higher rates of infusion related reactions (IRRs) when compared to the subcutaneous (SC) formulation. We report real world safety outcomes and infusion chair time savings associated with SC administration in daratumumab naïve patients. We retrospectively analyzed medical records at our institution for the incidence and severity of IRRs following differing observation periods post SC daratumumab administration. Infusion chair time was calculated to quantify chair time savings with SC administration. Sixty-six daratumumab naïve patients were included. Nine percent of patients developed IRRs with SC daratumumab with all reactions occurring within six hours of the first dose. All reactions were grade ≤ 2 in severity and were reversible with supportive care. Over the 18 month study period, a total of 904 SC doses were administered, amounting to a potential 1785 hours of infusion chair time savings when compared to IV administration. SC daratumumab may be given safely with a short initial observation period and without observation for subsequent doses, resulting in reduced infusion chair time as well as administration related cost and resources.