Upper gastrointestinal tract transit times of tablet and drinkable solution formulations of alendronate: a bioequivalence and a quantitative, randomized study using video deglutition.

The bioequivalence and upper digestive tract transit time of a drinkable solution of 70 mg/100 mL alendronate was compared to reference tablets. A randomized, single- dose, two-way crossover study of the rate of urinary recovery of alendronate during 36 h (AE((0-36 h))) by HPLC, in 104 healthy young male volunteers, showed that AE((0-36 h)) and the maximum excretion rate (R (max)) were within the accepted range of bioequivalence 81.8-105.7 and 81.7-106.2, respectively. To characterize the oesophageal passage time of the two alendronate formulations, we performed a randomized, controlled study, in 24 healthy men and women (mean 52 years old), who took the formulations standing or lying down, by an X-ray video deglutition system. When taken in the standing position, both formulations had equal mean transit times from mouth to stomach and tablet disintegration but data dispersion was significantly smaller with the liquid form. When taken in lying position, drinkable alendronate had shorter and less variable median transit times compared to the tablets. These results show that the drinkable alendronate formulation is bioequivalent to the tablets and may be advantageous in patients in whom the transit or disintegration of the tablets is impaired.