Branded Compared with Generic Latanoprost in Glaucoma Therapy: Where Do We Stand?

In this literature review, branded and generic preserved latanoprost are compared with respect to comparative efficacy, tolerability, and physicochemical properties. Worldwide, latanoprost, a prostaglandin analogue, has evolved into the first-line medical treatment for patients with open-angle glaucoma or ocular hypertension. Following the launch of multiple latanoprost generic preparations, clinicians and patients face a dilemma between prescribing the original branded product or its more affordable generic counterparts. While, in theory, branded and generic latanoprost formulations share the same active and inactive ingredients, available studies comparing their efficacy have reported conflicting results. Further, published evidence has demonstrated several subtle and sometimes manifest differences in terms of active ingredient content, benzalkonium chloride (BAK) concentration, pH level, osmolality, particulate content, and drop size. Moreover, degradation of the active ingredient under adverse temperature conditions is reportedly more pronounced with generic latanoprost. Recorded differences may negatively affect long-term efficacy, tolerability, ocular surface health, and adherence. However, to what extent these differences play a role in glaucoma care over the long term remains to be determined. Until such information becomes available, latanoprost therapy should be individualized, and careful patient monitoring is recommended. We conclude that stricter regulatory oversight of antiglaucoma eyedrops should be sought to ensure the safety and consistency of action of all available generic formulations.