Successful Conversion and Implementation to Subcutaneous Daratumumab in Patients with Multiple Myeloma (MM) and Light Chain (AL) Amyloidosis

• Published in: Blood 2021-11, Vol.138 (Supplement 1), p.1975-1975
• Main Authors: Hughes, David, Henshaw, Lynnette, Blevins, Frances, Edwards, Camille V, Lerner, Adam, Sloan, John Mark, Sanchorawala, Vaishali
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2021-147518

Introduction Intravenous (IV) daratumumab has become a standard in the treatment of MM and AL amyloidosis largely due to its significant clinical benefit. Due to the high risk of infusion-related reactions (IRRs) prolonged infusion times are required at time of treatment initiation. These lengthy administrations can limit clinic capacity, require split dose infusions, increase chair time, and decrease patient satisfaction. Fixed-dose subcutaneous (SC) formulation of daratumumab (daratumumab and hyaluronidase-fihj) was approved in 2020 for the treatment of MM and subsequently, AL amyloidosis in 2021. While landmark trials have demonstrated its efficacy, there is lack of consensus around the standardized pre-medications and post-injection monitoring times for SC daratumumab. We present real world evidence from a large academic center with adoption and standardization of SC formulation of daratumumab into clinical practice. Methods We evaluated all patients that received SC daratumumab for MM and/or AL amyloidosis at Boston Medical Center from June 1, 2020 to February 28, 2021. Baseline demographics were collected, including patient diagnosis, chemotherapy regimen, prior daratumumab administration details, and total doses of daratumumab received. Patients that were naïve to daratumumab, started their first dose as a SC injection. Patients were monitored for 30 minutes following the first SC dose and were pre-medicated with all oral agents: acetaminophen, dexamethasone, and diphenhydramine. Infusion chair time, improvement in clinic efficiency (using our standard infusion time of 90 minutes for IV daratumumab infusions after the 2nd dose), and safety were evaluated. Results A total of 41 patients were treated with SC daratumumab. Eighteen patients (44%) were switched from IV daratumumab to SC daratumumab. All other patients were naïve to SC daratumumab (n=23). All patients were monitored for 30 minutes after their first SC daratumumab dose only. In the absence of an ARR (administration-related reactions), patients were not monitored after subsequent injections. One patient had facial and neck swelling 2 days after administration of SC daratumumab (with no other symptoms) but resolved within 24 hours of an additional dose of dexamethasone and did not recur upon re-challenge of SC daratumumab. One patient experienced nausea following her first dose of SC daratumumab but it resolved without intervention. All patients received dexamethasone 20-40 mg (as anti-myelo