Sex and Food Influence on Intestinal Absorption of Ketoprofen Gastroresistant Formulation.

Sixteen healthy volunteers (8 women and 8 men) participated in a 2-period, 2-treatment crossover study. A delayed-release gastroresistant formulation of ketoprofen was administered under fasting and fed conditions. Cmax , AUC, Cmax /AUC, and kel obtained after food coadministration did not differ from those calculated under fasting administration. Ninety-five percent confidence intervals for fed/fasting geometric mean ratio of Cmax /AUC and AUC were 0.80-1.14 and 0.80-1.23, respectively. A significant difference (P < .01) was found between lag-time medians (T0 ), with a longer T0 after food intake (5.5 vs 2.5 hours). Also, a significant difference between the medians of Tmax was found (P < .01), being 7.0 hours after food coadministration and 4.0 hours under fasting administration, but this difference disappeared once T0 was subtracted from Tmax . Cmax /AUC, which is related to drug absorption rate, showed significant differences between sexes. Men showed higher (P =.006) Cmax /AUC means (0.468 ± 0.094 vs 0.361 ± 0.087 h(-1) . Tmax was also significantly different (P < .05), being 4.0 (3.0-5.0) hours for men and 8.0 (5.0-10.0) hours for women. In conclusion, men showed a faster intestinal absorption rate with earlier time-to-peak plasma concentration of ketoprofen. Food coadministration extended the gastric residence time of formulation but exerted no effect on its intestinal absorption pattern.