There is a need to discern predictive biomarkers in order to better identify patients at risk of developing VTE, to decipher the mechanisms by which myeloma treatments interfere and in fine to choose an adequate thromboprophylaxis. In this context, it is important to document the precise expression of coagulation factors and to profile point-of-care tests for coagulation monitoring in newly diagnosed MM patients, before and during treatment. In addition, thromboprophylaxis is systematically included in therapeutic MM strategies, especially direct oral anticoagulants, without knowing whether potential drug interactions are occurring. This study aims at evaluating and validating predictive biomarkers of VTE in MM, and at identifying patients whose thromboprophylaxis is required and may potentially be adjusted because of drug interactions.