Interchangeability Issues with Glaucoma Medicines Using Latanoprost as an Example

Abstract

The possible interchangeability of eye drops was analyzed using glaucoma medicines containing latanoprost as examples. It was shown that the reference and generic drugs could be identical with respect to composition of active ingredients when manufactured from the same pharmaceutical substance but could differ in the excipient composition, in particular, have a different buffer and osmolality that could produce differences in their clinical effects. An analysis of the literature showed that the therapeutic efficacy and safety could vary for pharmaceutically equivalent drugs. The lack of therapeutic equivalence on the background of pharmaceutical equivalence could be caused by the use of different packaging and different dosing systems. Therefore, results from clinical trials must be compared to confirm the interchangeability of eye drops.