Daily costs of prostaglandin analogues as monotherapy or in fixed combinations with timolol, in Denmark, Finland, Germany and Sweden

Abstract

Anders Bergström1, Frédérique Maurel2, Claude Le Pen3, Emilie Lamure2, Michael Kent4, Isabelle Bardoulat2, Gilles Berdeaux5,61Lund Hospital, Lund, Sweden; 2IMS France, Puteaux, France; 3Université Paris-Dauphine, Paris, France; 4Alcon Inc, Fort Worth, Texas, USA; 5Alcon France SA, Rueil-Malmaison, France; 6Conservatoire National des Arts et Métiers, Paris, FranceBackground: To compare the daily costs of 3 prostaglandin analogues (bimatoprost, latanoprost, travoprost), alone, and associated with timolol in 4 European countries (Denmark, Finland, Germany, and Sweden).Methods: Six glaucoma products were sampled by buying 5 bottles from 1 suburban pharmacy in each of the 4 countries. Drops were weighed by a single operator at 1 site according to standardized procedures. Residual drops were then counted. Unit bottle costs were estimated from tariff lists. Eye-drop weights were entered into a nested analysis of variance comprising drug, instillation day, country, the interaction, and a sample factor nested within the country factor. Effectiveness was represented by treatment failure rates estimated from a meta-analysis and a general practitioner survey.Results: Every drug bottle contained sufficient drops to treat 1 patient for 28/31 days. Drop-size heterogeneity between countries was observed for bimatoprost and bimatoprost/timolol. Mean travoprost and travoprost/timolol drop-sizes were the smallest, and drop-counts per bottle were the lowest for latanoprost, or latanoprost/timolol. In all 4 countries annual costs were least for travoprost and travoprost/timolol.Conclusions: On taking into account drug costs and effectiveness, travoprost and travoprost/timolol were cheaper and more effective than latanoprost and latanoprost/timolol and were cheaper than bimatoprost and bimatoprost/timolol.Keywords: prostaglandin analogue, economics, daily cost