Drug*placebo interaction effect may bias clinical trials interpretation: hybrid balanced placebo and randomized placebo-controlled design.

Background: Conventional randomized placebo-controlled study design assumes the absence of drug*placebo interaction. We hypothesized the presence of such an interaction and that conventionally estimated drug effect might be biased. The objectives of the study were to determine the drug*placebo interaction effect (main) and compare conventionally estimated and interaction model-estimated drug effects (secondary).

Patients' perceived purpose of clinical informed consent: Mill's individual autonomy model is preferred.

Background: Although informed consent is an integral part of clinical practice, its current doctrine remains mostly a matter of law and mainstream ethics rather than empirical research. There are scarce empirical data on patients' perceived purpose of informed consent, which may include administrative routine/courtesy gesture, simple honest permission, informed permission, patient-clinician shared decision-making, and enabling patient's self decision-making. Different purposes require different processes.

Consenting options for posthumous organ donation: presumed consent and incentives are not favored.

Background: Posthumous organ procurement is hindered by the consenting process. Several consenting systems have been proposed. There is limited information on public relative attitudes towards various consenting systems, especially in Middle Eastern/Islamic countries.

Interaction between drug and placebo effects: a cross-over balanced placebo design trial.

Background: The total effect of a medication is the sum of its drug effect, placebo effect (meaning response), and their possible interaction. Current interpretation of clinical trials' results assumes no interaction. Demonstrating such an interaction has been difficult due to lack of an appropriate study design.

Bioequivalence study of two metformin formulations.

A randomized single-dose cross-over study was conducted on 24 healthy male volunteers to compare the bioavailability of two metformin (CAS 657-24-9) tablet formulations, Emiphage (test) and a commercially available original preparation (reference). A dose of 850 mg was administered after an overnight fast with a washout period of seven days. Eighteen blood samples were collected over 32 h.

Bioequivalence evaluation of two rosiglitazone tablet formulations.

A randomized, two-period, two-sequence, crossover study was conducted on 28 healthy male volunteers to compare the bioavailability of two rosiglita-zone (CAS 122320-73-4) tablet formulations, a test and a commercially available original preparation (reference), under fasting conditions. The two preparations were given in a dose of 8 mg with a 7-day washout period between the two preparations. Eighteen blood samples were collected over 24 h, plasma rosiglitazone concentrations were determined by locally validated high performance liquid chromatography (HPLC) assay, and pharmacokinetic parameters were analyzed by the standard non-compartmental method.

Bioequivalence study of two amoxicillin formulations.

A randomized single-dose crossover study was conducted in 24 healthy male volunteers to compare the bioavailability of two amoxicillin (CAS 26787-78-0) formulations, Glomox tablet (test) and a commercially available original preparation, amoxicillin capsule (reference). One thousand milligram of each formulation were administered after an overnight fast with a washout period of three days. Sixteen blood samples were collected over 10 h, amoxicillin concentrations in deproteinized serum were determined by a high performance liquid chromatographic (HPLC) assay, and pharmacokinetic parameters were analyzed by the standard non-compartmental method.

Bioequivalence evaluation of two formulations of fluconazole 150 mg capsule in healthy Arab men.

A randomized crossover study was conducted on 26 healthy Arab males to compare the bioavailability of two formulations of fluconazole 150 mg capsules, Fluconazole (test) and Diflucan (reference). The formulations were administered after an overnight fast with a washout period of 2 weeks. Twenty blood samples (per period) were collected over 168 h, plasma fluconazole concentrations were determined by locally validated high performance liquid chromatography (HPLC) assay and pharmacokinetic parameters were analysed by the standard non-compartmental method.

Bioequivalence of two oral formulations of nizatidine capsules in healthy male volunteers.

Purpose: The purpose of this randomized, crossover study was to compare the bioavailability of a generic and an innovator formulation of nizatidine 300 mg capsules under fasting conditions.

Methods: Twenty blood samples per period were collected from 20 healthy, Arab male volunteers over 16 h, plasma nizatidine concentrations were determined by HPLC assay, and pharmacokinetic parameters were determined by the non-compartmental method.

Results: Mean+/-SD C(max), T(max), AUC(0-->t), AUC(0-->infinity), and t1/2 were 2.