The aim of this study is to evaluate the efficacy and safety of aspirin and rivaroxaban in thromboprophylaxis in Chinese MM patients at high risk for MM-associated VTE.

Venous thromboembolism (VTE) is one of the most common and dangerous complications of Multiple Myeloma (MM). The occurrence of VTE can disrupt treatment plans, compromise patients' quality of life, and even threaten their lives, presenting significant challenges in clinical management. Although several guidelines recommend risk-stratified thromboprophylaxis, there is a deficiency in prospective validation, and most initial studies were conducted in Western cohorts. This prospective, multicenter, open-label, randomized study aims to compare the efficacy and safety of aspirin or rivaroxaban in preventing VTE in Chinese MM patients who are at high risk for VTE.

Inclusion Criteria:

1. Newly diagnosed multiple myeloma (according to Guidelines for the diagnosis and management of multiple myeloma in China (2022 revision))
2. High risk of VTE (according to Expert consensus on the prevention and treatment of multiple myeloma related venous thromboembolism in China (2022))
3. Life expectancy exceeding 12 months
4. Gender: not specified, Age: 18-90 years
5. Serum HIV antigen or antibody negative
6. HCV antibody negative, or HCV antibody positive with HCV RNA negative
7. Echocardiogram shows a left ventricular ejection fraction of ≥50%
8. Ability to sign an informed consent form

Exclusion Criteria:

1. Pregnant women or women who are breastfeeding
2. Active gastrointestinal ulceration
3. Active bleeding
4. When initiating treatment, platelet count below 50 G/L, or with PT prolonged by more than 3 seconds, and APTT prolonged by more than 10 seconds.
5. Abnormal liver function (ALT or AST greater than 3 times the upper limit of normal, or total bilirubin greater than 2 times the upper limit of normal)
6. Abnormal renal function (creatinine clearance < 30 mL/min)
7. Unable to cooperate in completing the clinical trial
8. Already enrolled in other clinical studies
9. Diagnosed with smoldering multiple myeloma or plasma cell leukemia
10. Patients already on antiplatelet therapy for other cardiovascular or cerebrovascular diseases.