Efficiency of glaucoma drug regulation in 5 European countries: a 1995-2006 longitudinal prescription analysis.

Purpose: To compare the evolution of prostaglandin analog (PGA) and β-blocker (BB) prescriptions across 5 European countries.

Methods: Data were extracted from various sources: (1) IMS data for France, Germany, Italy, Spain, and the United Kingdom, (2) glaucoma-treated patients from the United Kingdom General Practice Research Database (UK-GPRD), (3) prescriptions delivered by the territorial pharmaceutical service of Monselice of the Padova region (Italy). Drugs were grouped into 3 classes: PGAs, BBs, and other drugs. Yearly market shares were calculated. Treatment persistence survival curves were estimated for Italian and UK data, and the 3 drug groups were compared using the Cochran Mantel Haenszel test.

Results: According to Padova data, BBs decreased in market share, whereas PGAs increased. A linear extrapolation of these market shares, based on 1998 to 2003 data, predicted that the 2 curves should cross in 2005, a prediction reinforced by the European Medicines Agency authorization (2002) of PGAs as first-line glaucoma treatments. That this did not occur may be explained by Italy's refusal to reimburse PGAs as first-line therapy. IMS data identified Italy and Germany as 2 countries in which BBs are still more frequently prescribed than PGAs. Treatment persistence with PGAs as monotherapy, in PGA-naive patients, was longer than for BBs according to both Padova and UK-GPRD data. This held true for both first-line and second-line PGA prescriptions (UK-GPRD); the persistence of second-line PGA equalled first-line BB treatment.

Conclusion: Health care regulations impacted upon glaucoma prescribing and may be one of the reasons for different annual evolution rates of PGA and BB prescriptions.