Biosimilar of the monoclonal antibody immunoglobulin G1κ daratumumab in treatment regimens for multiple myeloma patients

Abstract

Objeсtive : To evaluate the direct medical costs of treating multiple myeloma (MM) patients with daratumumab and its Russian biosimilar using subcutaneous (SC) and intravenous (IV) administration routes, while considering the patients’ body weights. Material and methods. The targeted patient population and their weight characteristics were determined according to the MM patients registry at the Hematology Center of Moscow Botkin Multidisciplinary Scientific and Clinical Center. As of February 16, 2026, it included 329 patients treated with daratumumab or its combinations. The costs of a year-long course of therapy were calculated, including the following treatment strategies: daratumumab alone (both SC and IV), a biosimilar alone, or a combination of the two, depending on the patient's weight. Furthermore, cost-minimization and budget impact analyses were conducted within a 1-year timeframe for the considered treatment strategies. These analyses evaluated the direct medical costs of daratumumab therapy based on the dosing regimens outlined in the clinical guidelines and the summary of product characteristics. Results . The cost-minimization analysis revealed that treatment strategies for MM patients using daratumumab biosimilar alone or in combination (for patients weighing less than 88 kg) with the SC route of the original drug (for patients weighing 88 kg or more) are the most cost-effective. The estimated costs are 4.28 and 4.18 million rubles, respectively, in the first year of treatment and 2.43 and 2.37 million rubles in the second and subsequent years. Meanwhile, solely IV or solely SC administration of the original daratumumab results in a 14.2% and 19.1% increase in costs, respectively, reaching 5.10 and 4.89 million rubles in the first year of therapy and 2.90 and 2.78 million rubles in the second and subsequent years. Also, combining IV and SC forms of the original drug increases costs by 7.8%, reaching 4.62 million rubles in the first year of therapy and 2.62 million rubles in subsequent years. The budget impact analysis revealed that using a daratumumab biosimilar for all patients who received treatment in 2025 would result in total annual savings for the healthcare system of between 701.32 and 1,714.83 million rubles. Conclusion . Expanding the use of the daratumumab biosimilar is cost-effective, compared not only to the IV form of the original drug but also to the SC form, as well as their combination.