SAFETY AND EFFECTIVENESS OF REPLACING STANDARD DOXAZOSIN WITH DOXAZOSIN IN THE GASTROINTESTINAL THERAPEUTIC SYSTEM (GITS) FORMULATION IN ELDERLY HYPERTENSIVE PATIENTS

Abstract

SUMMARYThe objective of this paper is to evaluate the safety and effectiveness of using doxazosin standard formulation in elderly hypertensive patients who were either uncontrolled or newly diagnosed, and replacing standard doxazosin with doxazosin in the gastrointestinal therapeutic system (GITS) formulation. We designed a postmarketing surveillance, open‐label non‐comparative, multicentre, clinical study covering primary care patients aged 65 years or older diagnosed with essential uncontrolled arterial hypertension. The study covered a period of 6–9 months, divided into two phases. Phase I involved a minimum of three and maximum of six months in treatment with standard doxazosin; phase II began with the changeover from standard doxazosin to the GITS formulation and lasted 12 weeks. Of the 1705 patients initially enrolled, 1292 (75.8%) completed the study. Reduction in systolic blood pressure was 22.3 mmHg (13.7%) in phase I, and 3.9 mmHg (2.77%) in phase II; reduction in diastolic blood pressure was 12.4 mmHg (13.2%) in phase I, and 2.4 mmHg (2.9%) in phase II. The percentage of controlled patients was 40.5% (691/1705) by the end of phase I and 45.3% (776/1705) by the end of phase II. A total of 154 patients suffered adverse events (AE), 127 during phase I and 27 in phase II. We conclude that doxazosin in its two formulations is effective and safe for the purpose of lowering blood pressure in elderly patients.