Randomized, Crossover and Single-Dose Bioquivalence Study of Two Oral Desogestrel Formulations (Film-Coated Tablets of 75 µg) in Healthy Female Volunteers.

Despite the increase in the substitution of branded medicinal product with generic drugs, this is a controversial issue for some pharmacological groups (such as contraceptives).The aim of the present clinical trial was to assess the bioequivalence and tolerability of two oral formulations of desogestrel.Thirty-three healthy female volunteers participated in this randomized and two-way crossover study. During two separate experimental periods, with at least four weeks of washout period, women received a single oral dose of 75 µg of desogestrel from each of the formulations (test formulation and reference formulation). Desogestrel bioavailability was determined by the measurement of 3-ketodesogestrel plasma concentration.Pharmacokinetic parameters were comparable and the 90% CI for the ratio of C(max) (96.14-114.53%) and AUC(0-t) (105.73-123.83%) values for the test and reference formulations fell within the established regulatory interval (80-125%). Both formulations were also comparable in terms of tolerability.From the results of this study it can be concluded that test formulation (desogestrel 75 µg, Cyndea PHARMA S.L.) is bioequivalent to the reference formulation (Cerazet® 75 µg, Organon Española S.A.).

The Effect of Food and an Antacid on the Bioavailability of Dexketoprofen Trometamol.

This randomized three-way, crossover pharmacokinetic study was performed to determine whether food or an antacid alters the bioavailability of dexketoprofen trometamol. A total of 24 healthy volunteers received three single 25 mg doses of dexketoprofen trometamol administered either in fasting condition, after an antacid (Maalox® ), or after a high-fat breakfast. Each volunteer received the three treatments in a randomized order, with a 7-day washout period between treatments. Blood samples were taken at regular intervals up to 24 h after dose. Plasma dexketoprofen concentrations were determined by HPLC and the main outcome measures were area under curve of concentration vs. time (AUC0-∞ ), maximal plasma concentration (Cmax .), and time to reach maximal concentration (tmax ). Administration of an antacid 10 min before dexketoprofen trometamol had no clinically relevant effect on any of the pharmacokinetic parameters. Food did not alter the extent of absorption of dexketoprofen trometamol, but tmax was significantly increased and Cmax significantly decreased compared with the fasting state. In conclusion, we can state that neither antacid nor food has a significant effect on the overall bioavailability of dexketoprofen trometamol.

Antinociceptive Effects of S(+)-Ketoprofen and Other Analgesic Drugs in a Rat Model of Pain Induced Uric Acid.

We investigated the antinociceptive properties of dexketoprofen trometamol (S(+)-ketoprofen tromethamine salt; SKP), a new analgesic, antiinflammatory drug, using the pain-induced functional impairment model in the rat (PIFIR), an animal model of arthritic pain. SKP was compared with racemic ketoprofen tromethamine salt (rac-KP), R(-)-ketoprofen tromethamine salt (RKP), ketorolac (KET), and morphine (MOR). We also assessed the effects of flurbiprofen (rac-FB) and its enantiomers (SFB and RFB) in the same model. Groups of six rats received either vehicle or analgesic drug and antinociception was evaluated by evaluating the dose-response curves over time. SKP was an effective antinociceptive drug in this model and was almost equally potent by either oral or intracerebroventricular administration. The oral potency of SKP was similar to that of oral KET and greater than that of oral MOR. No significant differences were observed between racemic ketoprofen and its enantiomers when administered orally. In the rat, significant bioinversion of RKP to SKP occurs when RKP is given orally. After oral administration of RKP, SKP was detectable in 30 min and surpassed the concentration of RKP after 3 h. Nevertheless, when the compounds were given intracerebroventricularly, some stereoselectivity in favor of SKP was observed. Stereoselectivity was observed with flurbiprofen, an analogue of ketoprofen that does not undergo significant metabolic inversion. Whereas SFB was an effective antinociceptive, RFB had no antinociceptive effect at the doses tested when given either orally or intracerebroventricularly.

Bioavailability of S(+)-Ketoprofen After Oral Administration of Different Mixtures of Ketoprofen Enantiomers to Dogs.

Recent reports have disagreed on whether the bioavailability of S(+)-ketoprofen is affected by the presence of R(-)-ketoprofen. To examine this directly, we designed a randomized crossover study in beagle dogs. [14 C]- S(+)-ketoprofen trometamol and R(-)-ketoprofen trometamol were administered in the following percentage ratios: A, 99:1; B, 95:5; C, 90:10; D, 70:30; E, 50:50. Treatments were administered as a single oral dose of 1 mg/kg trometamol salt. Each of eight dogs received all five combinations in random order with a 1-week washout period between doses. Blood samples were taken before drug administration and at regular intervals for 240 min after dosing. A progressive increase in the plasma concentration of [14 C]-S(+)-ketoprofen was observed on going from treatment E (lowest dose of S-enantiomer) to treatments containing the highest doses of (14 C]-S(+)-ketoprofen. When the pharmacokinetic calculations were normalized to the dose of (14 C]-S(+)-ketoprofen, we found no statistically significant differences among the normalized AUC and Cmax values of the five treatments. Therefore, S(+)-ketoprofen absorption was linear and was not influenced by the presence of R(-)-ketoprofen. Furthermore, there were no significant differences in tmax values among treatments, indicating that the rate of S(+)-ketoprofen absorption was also unaffected by the presence of R(-)-ketoprofen.

Pharmacokinetics of Dexketoprofen Trometamol in Healthy Volunteers After Single and Repeated Oral Doses.

The pharmacokinetics of dexketoprofen trometamol were evaluated in two studies using healthy volunteers. In the first study, the relative bioavailability of a single oral capsule of dexketoprofen free acid 25 mg or dexketoprofen trometamol 25 mg (given as 37 mg of the trometamol salt) was compared to ketoprofen 50 mg in 18 healthy volunteers. In the second study, the pharmacokinetics and tolerability of oral dexketoprofen trometamol in tablet form were evaluated after either a single 25 mg dose (24 volunteers) or a repeated dose of 25 mg twice daily for 7 days (12 volunteers). The absorption of dexketoprofen from dexketoprofen trometamol capsules was bioequivalent to that of ketoprofen. On the other hand, the extent of absorption of dexketoprofen free acid was significantly lower than that for ketoprofen. Dexketoprofen trometamol showed the most rapid absorption rate, with highest Cmax and shortest tmax values, whereas dexketoprofen free acid had the slowest absorption rate, and ketoprofen had an intermediate absorption rate. After repeated-dose administration of dexketoprofen trometamol, the pharmacokinetic parameters were similar to those obtained after single doses, indicating that no drug accumulation occurred. Dexketoprofen trometamol was well tolerated, with no clinically relevant adverse events reported.