Stability of dabigatran etexilate (Pradaxa) capsules in dose administration aids

Abstract Background Recent studies produced conflicting results on the suitability of repackaging dabigatran etexilate (Pradaxa) capsules in dose administration aids (DAAs). Aim To determine the stability of Pradaxa capsules in climate zones II (25°C and 60% relative humidity [RH]) and IVa (30°C and 65% RH). Method Pradaxa 110 mg capsules were subjected to two storage conditions (25°C/60% RH and 30°C/65% RH) in both the original packaging and after repackaging into Webster packs. Content assay, appearance, pH, and dissolution profile of capsules were determined at baseline, and 2 and 4 weeks after storage. Ethics approval was not required for this research article as it was a stability study and did not contain human participants or human data. Results Dabigatran etexilate content (± standard deviation) decreased significantly after 4 weeks of storage in DAAs at 30°C/65% RH (87.7% ± 4.4%). In addition, the amount of dabigatran etexilate released from the capsules at 45 min was significantly lower for capsules repackaged in DAAs and stored at 30°C/65% RH at both time points. Considerable changes in the appearance of capsule content were also observed following storage at 30°C/65% RH for 4 weeks in DAAs. There were no significant changes to dissolution profile or drug content of capsules repackaged and stored at 25°C/60% RH. No significant changes in the pH of dabigatran etexilate solutions were observed. Conclusion Repackaging impacts the chemical stability of dabigatran etexilate if the DAAs are exposed to climate zone IVa conditions. Although repackaged dabigatran etexilate stored at 25°C/60% RH appears to be stable, caution should be exercised if these DAAs are to be stored at ambient room conditions due to the inability to guarantee humidity levels.