Thromboprophylaxis in multiple myeloma: is the evidence there?

Antithrombotic utilization, adverse events, and associations with treatment outcomes in multiple myeloma: pooled analysis of three clinical trials

Background

Patients with multiple myeloma (MM) are at risk of venous thromboembolism (VTE), worsened by immunomodulatory drugs. Although antithrombotics are recommended for prophylaxis, existing guidelines are suboptimal and treatment outcomes remain unclear.

Objectives

This study aimed to investigate adverse events, antithrombotic utilization, and their associations with survival outcomes in patients with MM initiating multi-drug immunomodulatory combinations.

Design

A posthoc analysis of individual-participant level data (IPD).

Methods

IPD from three daratumumab clinical trials (MAIA, POLLUX, and CASTOR) were pooled. Adverse events incidence and antithrombotic utilization were assessed. Logistic and Cox regression were utilized to examine associations between antithrombotics use with adverse events and survival outcomes at the baseline and 6-month landmark.

Results

Among 1804 patients, VTE occurred in 10%, bleeding in 14%, ischemic heart disease in 4%, and stroke in 2%. Patients with these adverse events demonstrated elevated rates of any grade ⩾3 events. Antiplatelet (primarily aspirin) and anticoagulant (primarily LMWH and direct oral anticoagulants) prescriptions have seen an increase from baseline (25% and 14%, respectively) to 6 months (35% and 31%). The primary indication for their use was prophylaxis. Anticoagulant use within 6 months was associated with reduced VTE (OR (95% CI) = 0.45 (0.26-0.77), p = 0.004), while antiplatelet use showed no associations with any evaluated adverse events. Antithrombotics and survival outcomes had no significant associations.

Conclusion

This study underscores the complexities of antithrombotic therapy and adverse events in MM and highlights the need for vigilant and proactive management due to increased grade ⩾3 adverse events. While anticoagulant use was associated with reduced VTE risk, further research is needed to optimize thromboprophylaxis guidelines and explore antithrombotic efficacy and safety in patients with MM.

Trial registration

MAIA (NCT02252172), POLLUX (NCT02076009), CASTOR (NCT02136134).

Development and validation of a new risk assessment model for immunomodulatory drug-associated venous thrombosis among Chinese patients with multiple myeloma

BACKGROUND

Individuals with multiple myeloma (MM) receiving immunomodulatory drugs (IMiDs) are at risk of developing venous thromboembolism (VTE), a serious complication. There is no established clinical model for predicting VTE in the Chinese population. We develop a new risk assessment model (RAM) for IMiD-associated VTE in Chinese MM patients.

METHODS

We retrospectively selected 1334 consecutive MM patients receiving IMiDs from 16 medical centers in China and classified them randomly into the derivation and validation cohorts. A multivariate Cox regression model was used for analysis.

RESULTS

The overall incidence of IMiD-related VTE in Chinese MM patients was 6.1%. Independent predictive factors of VTE (diabetes, ECOG performance status, erythropoietin-stimulating agent use, dexamethasone use, and VTE history or family history of thrombosis) were identified and merged to develop the RAM. The model identified approximately 30% of the patients in each cohort at high risk for VTE. The hazard ratios (HRs) were 6.08 (P < 0.001) and 6.23 (P < 0.001) for the high-risk subcohort and the low-risk subcohort, respectively, within both the derivation and validation cohorts. The RAM achieved satisfactory discrimination with a C statistic of 0.64. The stratification approach of the IMWG guidelines yielded respective HRs of 1.77 (P = 0.053) and 1.81 (P = 0.063). The stratification approach of the SAVED score resulted in HRs of 3.23 (P = 0.248) and 1.65 (P = 0.622), respectively. The IMWG guideline and the SAVED score-based method yielded C statistics of 0.58 and 0.51, respectively.

CONCLUSIONS

The new RAM outperformed the IMWG guidelines and the SAVED score and could potentially guide the VTE prophylaxis strategy for Chinese MM patients.

Comparison of three risk assessment models for thromboembolism in multiple myeloma patients receiving immunomodulators: a Brazilian historical cohort

Venous thromboembolism (VTE) is among the complications of Multiple Myeloma (MM) and may occur in up to 10% of this patient population. However, medications used in MM therapy such as immunomodulators (IMID) may raise these rates. Thus, risk prediction models have been developed to quantify the risk of VTE in MM patients. The aim of this study is to compare the performance of three risk assessment models for VTE in newly diagnosed MM (NDMM) patients using immunomodulatory agents. A historical cohort study during a 10-year period in a Brazilian metropolis with NDMM treated with IMID. Data were collected from patient's medical charts for the period of one year to calculate the scores using IMPEDE VTE, SAVED, and International Myeloma Working Group (IMWG) guidelines. The area under the curve (AUC) of the Receiver Operating Characteristic curve analysis was calculated to assess the discriminative power of three risk assessment models. We included 131 patients (9 in the VTE group versus 122 in the non VTE group). According to IMPEDE, 19.1, 62.6, and 18.3% of patients were considered low, intermediate, and high risk, respectively. SAVED classified 32.1% as high risk and 64.9% had ≥2 risk factors based on IMWG guidelines. The AUC of the IMPEDE VTE score was 0.80 (95% CI 0.66-0.95, p = 0.002), of the SAVED score was 0.69 (95% CI 0.49-0.89, p = 0.057), and of the IMWG risk score was 0.68 (95% CI 0.48-0.88, p = 0.075). IMPEDE VTE was the most accurate in predicting the development of VTE in Brazilian patients on IMID therapy. The SAVED score and the IMWG guidelines did not show discriminative ability in predicting VTE based on the population involved in this study.

Real-life practices for preventing venous thromboembolism in multiple myeloma patients: a cohort study from the French health insurance database

PURPOSE

The risk of venous thromboembolic event (VTE) in multiple myeloma is particularly increased. Current guidelines recommend systematic VTE prophylaxis with vitamin K antagonists (VKA) or low weight molecular heparin (LWMH) or unfractionated heparin (UFH) in high-risk patients, based on treatment received [e.g. use of IMiDs (thalidomide, lenalidomide and pomalidomide), alkylating agents or erythropoietin] and individual risk factors (e.g. history of VTE). The aim of this study was to describe strategy of VTE prophylaxis and prescribing of other antithrombotic agents during the first 6 months of multiple myeloma therapy, with stratification on IMiD-based regimens and drug and disease-related risk factors.

METHODS

A retrospective cohort study of French beneficiaries from the health insurance database (SNIIRAM, Système National d'Information Inter-Régime de l'Assurance Maladie) was designed in the Midi-Pyrénées area (South West France). Patients starting a treatment for multiple myeloma in the period 2011-2014 were identified through hospital and chronic disease diagnoses.

RESULTS

Among the 236 incident multiple myeloma patients, 56% male (n = 133), 67% >65 years (n = 159) and 47% (n = 110) patients received an IMiD-based regimen. In these patients, 63% (n = 69) were identified as high-risk patients with indication for low molecular weight heparin or equivalent, and 37% (n = 41) were identified as low-risk with aspirin recommended. Among the high-risk IMiDs patients, 43% (30/69) currently received a VTE prophylaxis after starting their first regimen: 70% LWMH (21/30), 40% VKA (12/30), 10% UFH (3/30) and 13% (4/30) other drugs (rivaroxaban and fondaparinux); 33% of the patients (23/69) received an antiplatelet drug only, and 23% (16/69) did not receive any antithrombotic drug.

CONCLUSIONS

These results revealed lack of implementation of VTE prophylaxis in one out of high-risk multiple myeloma patients with IMiD. Copyright © 2017 John Wiley & Sons, Ltd.