Tolerability and Efficacy of Daratumumab in Patients with Plasma Cell Disorder with Poor Performance Status or Good Performance Status with CKD and/or CHF

Context: Daratumumab is an anti-CD38 monoclonal antibody used to treat plasma cell disorders. However, in clinical trials, patients with poor Eastern Cooperative Group performance status (ECOG-PS), poor renal and cardiac functions were excluded. The tolerability and efficacy of daratumumab in such populations is unknown. Objective: To determine the tolerability and efficacy of daratumumab in patients with poor ECOG-PS, poor renal or cardiac functions. Setting, Design, and Patients: We conducted a retrospective study on patients with MM and AL amyloidosis, who had ECOG-PS of 3-4, or ECOG-PS 1-2 with CrCl of Results: Median age of the patients was 69 years with female predominance (56%). Majority of the patients were Caucasian (72%). Twenty-nine (81%) patients had MM and 7 (19%) had AL amyloidosis. The median duration of therapy was 9.0 months (range, 1.5-25 months), and median number of cycles of daratumumab received by each patient was 9 (range, 1-27). Average duration of therapy was 12.7 months, 10.9 months, 7.1 months, and 6.3 months for ECOG-PS 1, 2, 3, and 4, respectively. Average number of cycles of daratumumab therapy was 14, 12, 8, and 6 for ECOG-PS 1, 2, 3, and 4, respectively. Overall response rate was 64%. Ten (28%) patients had stable disease, and 3 (8%) had disease progression. Therapy was discontinued due to disease progression in 13 (81%), death of 2 (13%), and to have transplant in 1 (6%) patients. Daratumumab was not discontinued in any patient for intolerance. Fourteen (39%) patients required hospitalization while on daratumumab therapy, due to infection (24%), dehydration and electrolyte imbalance (12%), and syncope/fall (8%). Conclusion: Our study, although had a small sample size and heterogeneous patient population, showed that daratumumab-based therapy is relatively safe, effective, and well tolerated by patients with poor PS, advanced kidney disease, and poor cardiac function.