Health economic impact of olopatadine compared to branded and generic sodium cromoglycate in the treatment of seasonal allergic conjunctivitis in the UK

Objective: This study estimated the health economic impact of olopatadine (Opatanol*) compared to branded cromoglycate (Opticrom dagger) and generic sodium cromoglycate in the treatment of seasonal allergic conjunctivitis (SAC) in the UK. Design and setting: This was a modelling study performed from the perspective of the UK's National Health Service (NHS). Methods: A decision model was constructed depicting the management of SAC sufferers who are 4 years of age or above over a typical allergy season of 4 months and considers the decision by a GP to initially treat a patient with olopatadine, branded or generic cromoglycate. The analysis assumed both drugs to be equally effective. Consequently, a cost-minimisation analysis was performed to identify the least costly alternative. Main outcome measures and results: Starting treatment with olopatadine is expected to lead to a healthcare cost of 92 pound (95% CI: 46; pound 150) pound over 4 months compared to 109 pound (95% CI: 65; pound 166) pound with branded cromoglycate and 95 pound (95% CI: 51; pound 152) pound with generic cromoglycate, resulting in a 16% and 3% reduction in healthcare costs respectively over 4 months of treatment. This cost-difference is primarily due to fewer GP visits among olopatadine-treated patients. Conclusion: Use of olopatadine instead of branded or generic cromoglycate affords an economic benefit to the NHS. Hence, within the limitations of the model, olopatadine is the preferred first-line treatment for use in SAC sufferers, since it is expected to lead to fewer GP visits, thereby releasing healthcare resources for alternative use.