Preference for and acceptability of two formulations of a dietary supplement containing calcium plus vitamin D-3: A randomized, open-label, crossover trial in adult patients with calcium and vitamin D deficiencies

Background: Preference for and acceptability of a drug are crucial for compliance and hence optimal treatment of diseases that require long-term management (eg, osteoporosis). The preference for and acceptability of a chewable tablet containing calcium and vitamin D-3 and a dose-comparable effervescent powder were assessed in a Phase 4, randomized, open-label, crossover trial in 5 European countries (Sweden, Finland, Belgium, the Netherlands, and Greece). Objective: The aim of the present analysis was to compare the preference for and acceptability, including tolerability, of these 2 formulations based on the Belgian results of the previously mentioned study. Methods: Patients were recruited from 3 osteoporosis units and university hospitals in Brussels, Liege, and Ghent, Belgium. Adult patients at risk for calcium and vitamin D deficiencies were enrolled. The study drugs included 2 formulations of a dietary supplement containing a combination of calcium plus vitamin D-3: chewable tablets (calcium carbonate, 1250 mg; vitamin D-3, 400 IU) (A) and effervescent powder (calcium carbonate, 1250 mg; vitamin D-3, 440 IU) (B). Patients were randomly assigned to receive 1 of 2 treatment sequences: AB or BA. Both formulations were given PO BID for 14 days, with a switch to the alternate formulation occurring on day 15 of the study. Preference and acceptability were assessed using 2 questionnaires: one assessed 5 variables of acceptability using 11-point scales, and the other assessed preference using yes/no questions. Compliance and tolerability were recorded throughout the study, with unused dose counts and recording of adverse events (AEs), respectively. Results: The study comprised 200 patients, 199 of whom received at least 1 dose of study medication and were included in the intent-to-treat analysis (174 women, 25 men; mean age, 66 years [range, 30-87 years]). Preference data were available in 178 patients, 129 of whom (72.5%) preferred the chewable tablet compared with 34 (19.1%) who preferred the effervescent powder and 15 (8.4%) who had no preference (both, P < 0.001 vs tablet). The preference for the tablet was based on consistently and significantly higher mean scores on all 5 variables of acceptability (all, P < 0.001). The most common AEs were gastrointestinal (tablet, 27/192 patients [14.1%]; powder, 31/190 patients [16.3%]). Eighteen patients (9.0%) discontinued the trial due to >= 1 AE (12 receiving the tablet and 6 receiving the powder). Conclusions: In this study of preference for and acceptability of 2 formulations (chewable tablet and effervescent powder) of a dietary supplement containing a combination of calcium plus vitamin D-3 in Belgian adults at risk for calcium and vitamin D deficiencies, the chewable tablet was preferred by a significant majority. Based on 5 variables, the tablet was found to be significantly more acceptable than the powder. Tolerability was similar between the 2 formulations. Copyright (c) 2005 Excerpta Medica, Inc.