Physicochemical stability of daratumumab SC (DARZALEX® 1800 mg injection solution) in plastic syringes over a period of 28 days stored refrigerated or at room temperature
University Medical Center Mainz, Germany
In multiple myeloma patients, the subcutaneous (SC) formulation of daratumumab (DARZALEX® 1800 mg injection solution) is increasingly used instead of the intravenous (IV) form due to practicability issues (fixed dose, short application time), safety, and efficacy. Only recently, the manufacturer (Janssen-Cilag International NV) specified the physicochemical stability of Daratumumab SC withdrawn into plastic syringes for 24 hours at 2-8°C protected from light and another 12 hours at room temperature (15-25°C) at ambient light for the prepared syringe . The aim of the study was to determine the prolonged physicochemical stability of ready-to-administer DARZALEX® 1800 mg injection solution in different types of syringes over a 28-day period.
Daratumumab (DARZALEX® 1800 mg injection solution) was withdrawn from vials and transferred to disposable 3-piece Luer-lock syringes (BD Plastipak Luer-Lock-Spritzen 20 mL, Original-Perfusor®-Spritzen 50 mL B. Braun). The syringes were capped with combi-stoppers (Combi-Stopper B. Braun) and stored at 2-8°C or at room temperature (22 2°C) over a maximum period of 28 days protected from light. Samples were taken immediately after preparation (0) and after 2, 7, 14, 21 and 28 days. Physicochemical stability was determined by size-exclusion and ion-exchange chromatography (SEC, IEC) with UV detection, pH measurement, and visual inspection for particles or colour changes.
In the SEC assay, neither the formation of aggregates nor of fragments was detected independent from syringe type or storage temperature. Daratumumab concentrations declined less than 5% over the entire test period under all storage conditions. The IEC peak areas remained constant and showed no significant changes of charge variants over time. pH values of all samples remained constant (5.6-5.7). All samples remained clear, no colour changes or visible particles could be detected.
Daratumumab SC (DARZALEX® 1800 mg injection solution) is physicochemically stable in capped plastic syringes (BD Plastipak Luer-Lock-Spritzen 20 mL, Original-Perfusor®-Spritzen 50 mL B. Braun) for at least 28 days when stored at 2-8°C or at room temperature (22 2°C) protected from light. For microbiological reasons storage under refrigeration is recommended.
 Darzalex Summary of product characteristics. https://www.ema.europa.eu/en/documents/product-information/darzalex-epar-product-information_en.pdf