Testing of parenteral drug products for visible particles: comparison of the Ph. Eur. method with an alternative method using polarised light.

OBJECTIVES: Parenteral drug products should be essentially free from visible particulate contamination. To ensure this, every batch produced must be subject to a 100% visual inspection. Monograph 2.9.20 of the European Pharmacopoeia (Ph. Eur.) describes a method for visual inspection of parenteral drug units in front of a black and white panel using a white light source. Nevertheless, several Dutch compounding pharmacies rely on an alternative method for visual inspection by means of polarised light. The objective of this study was to compare the performance of both methods. METHODS: Trained technicians in three different hospitals inspected a predetermined set of samples using both methods for visual inspection of parenteral drugs. RESULTS: The results of this study show that the alternative method for visual inspection yields a higher recovery than the Ph. Eur. method, while no significant difference in false positive results was found. CONCLUSIONS: Based on these findings, it can be concluded that the alternative method for visual inspection by means of polarised light can very well replace the Ph. Eur. method in pharmacy practice, provided that local validation of the alternative method is performed.

Safety assessment and pharmacokinetics of intrathecal methylprednisolone acetate in dogs.

BACKGROUND: Intrathecal methylprednisolone acetate (MPA) has been used in patients with chronic pain syndromes. Its safety has been debated after reports of adverse events. No systematic preclinical evaluation of MPA has been reported. In the current study, the acute and long-term effects of intrathecal MPA on dog spinal tissue was studied with the injectate reformulated to include minimal adjuvants. METHODS: Seventeen dogs were implanted with intrathecal catheters and randomized to three groups: vehicle (lidocaine; 4 dogs), MPA 20 mg/ml (human dose; 7 dogs), and MPA 80 mg/ml (maximum deliverable dose; 6 dogs). In parallel with the human protocols, dogs received four injections at 7-day intervals. Clinical observations and plasma methylprednisolone measurements were done before and at intervals after intrathecal delivery. One week (acute) or 6 weeks (long-term) after the last injection, animals were sacrificed and spinal tissues harvested for histopathology. RESULTS: Other than a brief motor block, no adverse clinical event occurred in any animal. Group A (vehicle) showed minimal histologic changes (median histology-score; acute: 1.3, long-term: 1.0). Group B (MPA 20 mg/ml) had a diffuse inflammatory reaction (acute: 2.0, long-term: 3.0), group C (MPA 80 mg/ml) a severe inflammatory response, with large inflammatory masses (acute: 4.0, long-term: 7.0) The severity of the inflammatory reaction increased significantly with increasing dose at long-term sacrifice (acute P = 0.167, long-term P = 0.014). No neuronal injury, demyelination, or gliosis was seen in any animal. CONCLUSION: These results, showing dose-dependent intrathecal inflammatory reactions at MPA doses and injectate concentrations comparable to those used in humans, indicate that the continued use of this modality in humans is not recommended.