Aim

Comparative permeability analysis of the 3 following Latanoprost formulations intended for ophthalmic use: Xaloptic (Pol¬pharma S.A.), Xalatan (Pfizer Europe MA EEIG) and Monoprost (Thea Pharma S.A.) across human corneal epithelium (HCE-T culture model) in vitro.

Material and methods

Permeability analysis was performed under conditions suitable for latanoprost API (active pharmaceutical ingredient). Statistical analysis of permeability and drug quantity after passing across a cellular membrane was performed using ANOVA test and Tukey’s multiple comparison test (GraphPad Prism 6.00 for Windows, GraphPad Software, La Jolla California, USA).

Results

The following differences in permeability were noted between the analyzed drugs: The permeability rates for Xaloptic and Xalatan were 5.49 ± 1.64 x 10-6 cm/s and 4.66 ± 1.13 x 10-6 cm/s, respectively. Xaloptic showed the highest permeability through human corneal epithelium (23.70 ± 1.71 x 10-6 cm/s) and the highest conversion rate (28.13 ± 5.85%). As compared to Xaloptic, Xalatan slight, yet statistically significant differences with the permeability rate of 21.21 ± 1.29 x 10-6 cm/s and a conversion rate of 18.41 ± 2.96%). Monoprost demonstrated the lowest permeability (0.39 ± 0.07 x 10-6 cm/s) and the lowest conversion rate (0.34 ± 0.16%).

Conclusions

The differences in permeability and bioavailability between the 3 ophthalmic latanoprost formulations are attributable to the differences in their composition. They are also related to the content of preservative in each preparation.