Background and importance Studies evaluating the effect of short temperature excursions on the quality of the unopened vial of Sandoz rituximab biosimilar (SDZ-RTX) stored in the original outer box at the caregiver level are lacking.

Aim and objectives This out-of-fridge (OOF) study simulated the impact of temperature excursion on the quality of SDZ-RTX.

Material and methods The OOF study was subsequently performed after 36 months of storage in long-term conditions (5±3°C) by exposing three batches of SDZ-RTX to two storage conditions: (i) 25±2°C/60±5% relative humidity (RH) and (ii) 30±2°C/65±5% RH, for up to 21 days. The impact of the temperature excursion was evaluated using the following parameters: purity (cation exchange chromatography (CEX), size exclusion chromatography (SEC) and non-reducing capillary electrophoresis-sodium dodecyl sulfate (nrCE-SDS)), identity (CEX and liquid chromatography-ultraviolet (LC-UV) peptide mapping) and also potency (complement-dependent cytotoxicity (CDC)-bioactivity). Other analyses are presented in the Results section.

Results No notable change was observed after 21 days at both OOF conditions (i) and (ii) for identity (charge and primary structure), pharmaceutical tests (clarity, visible and subvisible particles, container appearance, degree of colouration, pH, osmolality, extractable volume and container closure integrity testing), protein content by UV and microbiological parameters. After 21 days, slight changes were detected with SEC (decrease in purity of up to 0.4%), CEX (decrease in the main peak up to 0.8%, decrease in the sum of basic peaks up to 2.4% and an increase in the sum of acidic peaks up to 3.9%) and nrCE-SDS (decrease in purity up to 0.9%). For CDC-bioactivity, a notable change was observed in only one out of three tested batches; however, all results complied with the shelf-life specification at both OOF conditions (i) and (ii).

Conclusion and relevance The obtained stability data support the storage of SDZ-RTX for up to 21 days up to 30±2°C/65±5% RH. These results may be beneficial to avoid potential wastage of product and prevent distressing the patients regarding drug quality after short-term exposure to conditions outside the intended storage of 2–8°C.

References and/or acknowledgements Under the direction of the authors, Amit Koushik, MS, Novartis, provided editorial support.

Conflict of interest No conflict of interest