Pharmacokinetics and relative bioavailability of a new chewable, buffered acetylsalicylic acid tablet formulation in comparison to a conventional plain tablet.

The pharmacokinetics of acetylsalicylic acid (ASA) and its main metabolite salicylic acid (SA) following single dose administration of a new chewable, buffered ASA tablet formulation and a conventional plain ASA tablet formulation were investigated in 12 healthy male subjects. The volunteers received in a randomized, crossover design two pharmaceutical units of both formulations containing 500 mg ASA each after an overnight fast on an empty stomach. ASA and SA in the collected plasma and urine samples were determined using an internally standardized validated HPLC method. Regarding the normalized extent parameters for ASA, an increase of about 114% for the maximum concentration (Cmax,norm) and about 16% for the area under the curve (AUC0----infinity,norm) was found for the new chewable, buffered tablet formulation as compared to the plain tablet. Comparing the corresponding parameters for the main metabolite, both formulations were statistically equivalent. The quotient of normalized areas (QAUC0-20min, norm/AUC0----infinity,norm) for ASA was higher by about 124% for the new formulation, indicating an increased and faster absorption during the first 20 min after administration. The time of the concentration maximum did not differ statistically. These data indicate that the new chewable, buffered ASA tablet formulation shows a significant benefit as compared to the plain ASA tablet. The new tablet produced higher plasma ASA concentrations in a shorter time, which is clinically important since higher ASA concentrations are assumed to be related to an improved analgesic efficacy.