A Prospective Open-Label Observational Study of a Buffered Soluble 70 mg Alendronate Effervescent Tableton Upper Gastrointestinal Safety and Medication Errors: The GastroPASS Study

Abstract

Upper gastrointestinal (GI) side effects are a main reason for discontinuing bisphosphonate treatment, an important therapeuticoption for osteoporosis patients. Consequently, the development of novel formulations with improved tolerability is warranted. Inthis multicenter prospective, observational, postauthorization safety study conducted in Italy and Spain, postmenopausal women(PMW) with osteoporosis (naïve to bisphosphonates) were treated weekly with a buffered soluble alendronate 70 mg effervescent(ALN-EFF) tablet (Binosto®) and followed for 12  3 months. Information was collected on adverse events (AEs), medication errors,persistence, and compliance using the Morisky-Green questionnaire. Patients (N = 1028) aged 67  9 years (mean  SD) receivedALN-EFF weekly. The cumulative incidence of upper GI AEs (oesophageal toxicity, gastritis, gastric ulcers, and duodenitis) relatedto ALN-EFF (primary endpoint) was 9.6% (95% condence interval [CI] 7.9–11.6%), the vast majority being of mild intensity. The mostfrequently occurring upper GI AEs related to ALN-EFF were dyspepsia (2.7%), gastroesophageal reux disease (2.4%), and nausea(2.2%). None of the relevant upper GI AEs listed in the primary endpoint and no serious AEs were reported. At least one medicationerror occurred in 29.9% (95% CI 27.1–32.8%) of patients. However, the majority of medication errors were associated with adminis-tration instructions applicable to any oral bisphosphonate and only seven medication errors were associated with the ALN-EFF for-mulation. ALN-EFF was discontinued in 209 of 1028 (20.3%) patients. The most frequent reasons for discontinuation were AEsrelated to ALN-EFF (46.9%) and patients’ decision (42.6%). Compliance with ALN-EFF was high, reected by a mean Morisky-Greenscore of 92.8  18.6. PMW with osteoporosis treated with ALN-EFF in a real-world setting experienced few upper GI AEs. In addition,they had a low discontinuation and high compliance compared with other formulations, suggesting that ALN-EFF may increasepatient satisfaction and therefore long-term adherence and efcacy