Mitigating the risk of venous thromboembolism in patients with multiple myeloma receiving immunomodulatory-based therapy

Patients with multiple myeloma (MM) have up to a 20-fold increased risk of venous thromboembolism (VTE) compared with the general population, with most events occurring within the first 6 months of diagnosis. Treatment with immunomodulatory drugs (IMiDs) is a strong risk factor for VTE in MM. In a meta-analysis of 2 large, randomized trials comparing anticoagulant thromboprophylaxis vs placebo in ambulatory patients with cancer at high risk of VTE based on a validated risk score, the risk of VTE decreased without increasing the risk of major bleeding. However, few patients with MM participated in these trials (1.1%). Initial guidance for risk-stratifying patients with MM resulted in persistent rates of VTE >10% and highlighted the need for improved VTE risk stratification in patients with MM. Three validated risk scores are now available to quantify risk of VTE in patients with MM: SAVED, IMPEDE VTE, and PRISM scores. Using best available data, thromboprophylaxis should be strongly considered in patients with MM assessed as high risk for VTE, especially newly diagnosed patients receiving IMiD-based combination therapies. However, prospective studies are needed to further validate available models and identify the optimal thromboprophylactic agent for each VTE risk category.