Comparative bioavailability of a novel timed release and powder-filled glucosamine sulfate formulation--a multi-dose, randomized, crossover study.

Objective: The absorption of 2 different formulations of glucosamine sulfate were studied in a randomized, multi-dose, two-way, crossover study.

Materials And Method: In this study, a novel timed release pellet-filled hard gelatin shell capsule (TimeOsamine) was compared with a powder-filled hard gelatin shell capsule. The timed release capsule was used in a double dose with an interval of 12 h whereas the powder-filled hard gelatin capsule was used in a triple dose schedule with an interval of 8 h after 10 h pre-dose fasting. Twelve healthy male subjects were administered a 1,000 mg (2 x 500 mg) dose of timed release glucosamine sulfate (TimeOsamine) or a 1,500 mg (3 x 500 mg) dose of the powder-filled glucosamine sulfate formulation. The concentration of glucosamine was measured over the next 24 h. Pharmacokinetics properties including area under the curve (AUC), maximum concentration in plasma (C(max)), time to maximum plasma concentration (t(max)) were measured.

Results: The C(max) of the powder-filled and timed release formulation (TimeOsamine) was 543.12 ng/ml and 520.98 ng/ml, respectively. The t(max) of TimeOsamine was delayed by 4.13 h, whereas the powder-filled preparation was 1.00 h. The AUC0-24 of the 2 doses of TimeOsamine (2 x 500 mg = 1,000 mg) and the 3 doses of the powder-filled formulation (3 x 500 mg = 1,500 mg) was 6,263.32 ng x h/ml and 6,499.55 ng x h/ml, respectively.

Conclusion: After reduction in the dose by 33%, the AUC0-24 of TimeOsamine is 96.37% with respect to the powder-filled formulation AUC0-24, which is comparable.