Clinical factors associated with venous thromboembolism in multiple myeloma patients treated with daratumumab.

Background: Venous thromboembolism (VTE) is a common cause of morbidity and mortality in patients with multiple myeloma (MM). There has been little evidence investigating the factors associated with VTE during therapy with daratumumab-containing regimens. Objectives: Our study examined the association of different clinical, medication- and procedure-related factors on the development of VTE events. Methods: We performed a retrospective chart review of multiple myeloma patients treated at our institution with daratumumab-containing regimens and who developed VTE within 12 months of starting daratumumab. We collected the information on clinical factors, cancer therapy, antithrombotic medications, and central venous access procedures during the observation period. A univariate logistic regression was done first to identify variables associated with VTE, after which those variables were entered into a multivariate analysis. Results: Among patients with MM who received a daratumumab-containing regimen, the incidence of VTE was 9.6% at 12 months from the initiation of daratumumab. We found that the number of PICC line insertions and the presence of multiple medical comorbidities were associated with VTE development. Conclusions: We conclude that VTE is frequent during therapy for MM, particularly in the presence of certain risk factors such as use of multiple PICC line insertions and recent infections. Our observations do not imply causality and limited by the retrospective design, small number of VTE events and lack of time-to-event analysis in the study.