Adverse Hematological and Non-Hematological Events in Patients With Relapsed/Refractory Multiple Myeloma That Are Responsive to Daratumumab, Pomalidomide and Dexamethasone.

Background: Daratumumab, pomalidomide, and dexamethasone (DPd) is an effective option for treatment of patients with relapsed/refractory multiple myeloma (RRMM). In this study, we sought to analyze the risk of hematological and non-hematological toxicities in patients who responded to DPd treatment.

Methods: We analyzed 97 patients with RRMM who were treated with DPd between January 2015 and June 2022. The patients and disease characteristics, as well as safety and efficacy outcomes were summarized as descriptive analysis.

Results: The overall response rate for the entire group was 74% (n = 72). The most common grade III/IV hematological toxicities in those who responded to treatment were neutropenia (79%), leukopenia (65%), lymphopenia (56%), anemia (18%), and thrombocytopenia (8%). The most common grade III/IV non-hematological toxicities were pneumonia (17%) and peripheral neuropathy (8%). The incidence of dose reduction/interruption was 76% (55/72), which was due to hematological toxicity in 73% of the cases. The most common reason for discontinuing treatment was disease progression in 61% (44 out of 72 patients).

Conclusions: Our study revealed that patients who respond to DPd are at high risk of dose reduction or treatment interruption because of hematological toxicity, typically due to neutropenia and leukopenia leading to increased risk of hospitalization and pneumonia.