Phase I clinical study to select a novel oral formulation for ibandronate containing the excipient sodium N-[8-(2-hydroxybenzoyl) amino] caprylate (SNAC)

The aim of this study was to select a novel oral formulation for ibandronate (IBN, CAS number: 13892619). In four cohorts of 28, 21, 19 and 29 healthy volunteers, the impact of the carrier molecule sodium N-[8-(2-hydroxybenzoyl) amino] caprylate (SNAC, CAS number: 203787-91-1) on the bioavailability of IBN was investigated. Within each cohort different oral formulations with one dose of ibandronate (30 mg) and three different ratios of IBN:SNAC (1:5, 1:10 and 1:20) were compared to the approved oral IBN tablet formulations (150 and 50 mg IBN) in a 4-way cross-over design and a one week washout between the administrations. The highest mean IBN exposure was achieved with a capsule formulation containing drug-coated beadlets and an IBN:SNAC ratio of 1:5. AUClast and Cmax of IBN were approximately 1.3- and 2.2-fold higher compared to the reference treatment (150 mg IBN without SNAC). Increasing the post-dose fasting duration from 15 to 30 min resulted in a more than 2-fold increase in AUClast, while superimposable IBN serum concentration-time profiles were achieved after a 30 and 60 min fast. The tolerability of the IBN/SNAC treatments in all cohorts was similar to that in the IBN reference groups and most adverse events (AEs) were of mild to moderate intensity.