Effects of the concomitant administration of tamsulosin (0.8 mg) on the pharmacokinetic and safety profile of intravenous digoxin (Lanoxin) in normal healthy subjects: a placebo-controlled evaluation

A 20-day, nonrandomized, open-label, placebo-controlled study was performed to investigate whether concomitant administration of tamsulosin (0.8 mg) affects the pharmacokinetic and safety profile of intravenous digoxin (0.5 mg) in healthy subjects. Ten healthy subjects aged 21-39 years received a single oral dose of placebo on study days 1-8 and tamsulosin on days 9-18. Tamsulosin was initiated at 0.4 mg/day and the dose was increased to 0.8 mg/day from day 11. On days 2 and 15, subjects received a single intravenous dose of digoxin (0.5 mg). Safety monitoring was carried out throughout the study. Following digoxin administration, blood was drawn and urine collected over a 96-h period for pharmacokinetic determinations. Plasma tamsulosin concentrations were measured at regular intervals after dosing on day 15. The digoxin pharmacokinetic parameters with and without concomitant tamsulosin were compared. No significant difference was observed, and no irregularity was found in the plasma tamsulosin concentration data. Six subjects experienced adverse events while receiving placebo and seven while on tamsulosin. The most frequent adverse event was mild dizziness reported by four subjects. Moderate chest pain was reported in two subjects, but this was not considered to be related to the administration of the study medications. Some significant changes in vital signs were observed; however, none was accompanied by symptoms of medical concern. These changes were not temporally related to the administration of study drugs. Thus, concurrent administration of digoxin with tamsulosin did not produce any change in the pharmacokinetics of digoxin and the safety profile was acceptable. As reflected in the prescribing information for tamsulosin, no adjustment in tamsulosin dosing is required when it is administered concomitantly with digoxin.

Effects of the concomitant administration of tamsulosin (0.8 mg/day) on the pharmacokinetic and safety profile of theophylline (5 mg/kg): a placebo-controlled evaluation

We performed a single-blind, sequential-design study to investigate the effects of concomitant oral tamsulosin 0.8 mg/day on the pharmacokinetics and safety of intravenous theophylline 5 mg/kg in healthy subjects. Ten healthy volunteers aged 19-39 years received placebo on study days 0, 1, 2 and 10 and tamsulosin on days 3-9. Theophylline was administered intravenously on days 1 and 9. Theophylline and tamsulosin pharmacokinetic data were determined following administration of the drugs on days 1 and 9 and day 9, respectively. No differences were observed in theophylline pharmacokinetic parameters with and without concomitant tamsulosin, and there were no abnormalities in tamsulosin pharmacokinetic data. Some significant changes in vital signs and a number of mild adverse reactions were reported, but the overall safety profile of tamsulosin and theophylline was acceptable. The results of the study suggest that no dose adjustment in tamsulosin is necessary when it is administered concomitantly with theophylline.

Review of orthostatic tests on the safety of tamsulosin, a selective alpha1A-adrenergic receptor antagonist, shows lack of orthostatic hypotensive effects

Two phase III studies with tamsulosin, a selective alpha1A-adrenergic receptor antagonist, were conducted to evaluate the safety and efficacy of the standard treatment doses of 0.4 mg/day and 0.8 mg/day in patients with symptoms of benign prostatic hyperplasia (BPH). These large-scale clinical trials were the first to include extensive testing for possible drug-induced orthostatic hypotension (OH). The frequency of positive orthostatic tests and magnitude of vital sign changes were compared among tamsulosin and placebo-treated groups. The results indicate that tamsulosin up to 0.8 mg/day does not induce higher risk of OH than that of placebo. Data from post-marketing surveillance (PMS) studies of tamsulosin indicate that the incidence of hypotension and syncope is extremely low in community-dwelling elderly men treated for BPH. From the results of the phase III studies, PMS studies and an active-controlled clinical pharmacology study, we conclude that the orthostatic test is a useful and convenient method to evaluate the risk of OH and syncope during the investigational stage.

Efficacy and safety of a 10-day course of 400 or 600 milligrams of grepafloxacin once daily for treatment of acute bacterial exacerbations of chronic bronchitis: comparison with a 10-day course of 500 milligrams of ciprofloxacin twice daily

A randomized, prospective, double-blind, double-dummy, multicenter study investigated the efficacy and safety of 10 days of oral therapy with grepafloxacin at 400 mg once daily, grepafloxacin at 600 mg once daily, or ciprofloxacin at 500 mg twice daily in 624 patients with acute bacterial exacerbations of chronic bronchitis. At the end of treatment, clinical success (cure or improvement) was achieved for 93% (140 of 151), 88% (137 of 156), and 91% (145 of 160) of patients in the groups receiving grepafloxacin at 400 mg, grepafloxacin at 600 mg, and ciprofloxacin, respectively (clinically evaluable population). At follow-up (14 to 28 days posttreatment), the clinical success rates were 87% (124 of 143), 81% (122 of 151), and 80% (123 of 154) in the groups receiving grepafloxacin at 400 mg and 600 mg and ciprofloxacin, respectively. A total of 379 pathogens were isolated from 290 patients, with the most common isolates being Moraxella catarrhalis (21%), Staphylococcus aureus (20%), Haemophilus influenzae (18%), and Streptococcus pneumoniae (7%). For the evaluable population, successful bacteriologic response was obtained at the end of treatment for 96% (92 of 96), 98% (87 of 89), and 92% (82 of 90) of patients receiving grepafloxacin at 400 mg, grepafloxacin at 600 mg, and ciprofloxacin, respectively, and was maintained in 86% (82 of 95), 88% (78 of 89), and 82% (69 of 84) of patients, respectively, at follow-up. All pretreatment S. pneumoniae isolates were susceptible to grepafloxacin, but two strains were resistant to ciprofloxacin. All treatments were well tolerated, with the most frequently reported drug-related adverse events being nausea, taste perversion, and headache. All drug-related adverse events in the grepafloxacin groups were mild or moderate in severity. This study demonstrates that 10-day courses of grepafloxacin given at 400 or 600 mg once daily were as effective, clinically and bacteriologically, as ciprofloxacin given at 500 mg twice daily for the treatment of acute bacterial exacerbations of chronic bronchitis.

Efficacy and safety of grepafloxacin 600 mg daily for 10 days in patients with community-acquired pneumonia

The efficacy and safety of grepafloxacin in treating patients with community-acquired pneumonia (CAP) was assessed in an open-label, noncomparative study. Patients (N = 273) received grepafloxacin 600 mg QD for 10 days. A total of 237 patients (87%) completed the study. In assessable patients, the clinical success rate at follow-up (4 to 6 weeks after the last dose) was 89% (211/238 patients). In microbiologically assessable patients, the eradication rate at follow-up was 95% (86/91 isolates). Grepafloxacin was highly effective in the treatment of bacterial CAP caused by Streptococcus pneumoniae (irrespective of penicillin susceptibility), Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, and Staphylococcus aureus and in the therapy of atypical pneumonia caused by Mycoplasma pneumoniae and Legionella pneumophila. Grepafloxacin was well tolerated, with the most frequently reported drug-related adverse events being taste perversion and nausea. Grepafloxacin 600 mg QD for 10 days was highly effective and well tolerated in the treatment of patients with CAP.

Multiple-dose pharmacokinetics and toleration of intravenously administered cefoperazone and sulbactam when given as single agents or in combination

The multiple-dose pharmacokinetics and toleration of cefoperazone (3 g every 12 h) and sulbactam (1.5 g every 12 h) were studied when these antimicrobial agents were administered continuously over 7 days as a 15-min infusion of individual agents and as a 3/1.5-g cefoperazone-sulbactam combination. Fourteen male volunteers participated in an open, three-way crossover study of Latin Square design with a 1-week washout period between phases. On days 1 and 7 of each phase, serial serum samples and urine were collected for drug assay over a 12-h period. Hematological and clinical chemistry determinations were made within 10 days before the first antibiotic dose and for each treatment phase just before the first dose, on day 4 of treatment, and within 24 h of the last dose. For cefoperazone as a single agent on days 1 and 7, the average maximal concentration in serum (Cmax) was approximately 430 micrograms/ml, the terminal elimination half-life (t1/2) was 1.8 h, and the average percentage of dose excreted unchanged in the urine (%Ur) was 30%. For sulbactam as a single agent, the Cmax was approximately 90 micrograms/ml, the t1/2 was 1 h, and the %Ur was 89% on days 1 and 7. When comparing individual versus simultaneous drug administration, the only pharmacokinetic alteration observed was a statistically significant but minor (about 10%) decrease in sulbactam renal clearance, on both days 1 and 7, resulting in a similar decrease in total body clearance (CL). The area under the curve, apparent volume of distribution by the area method (V), t1/2, and Cmax were not significantly altered. Although cefoperazone pharmacokinetic parameters were not significantly altered when comparing single-agent to combination drug administration, the area under the curve was slightly lower and CL, nonrenal clearance, and V were modestly higher from day 1 to day 7. Because Cmax and t1/2 were unaffected, these minor day effects would not be of clinical significance. Intravenous administration of cefoperazone and sulbactam given as individual agents compared with the combination did not show pharmacokinetic differences that are likely to produce clinically relevant effects. The combination of cefoperazone and sulbactam was well tolerated, and the safety profile of the combination was similar to that either drug given alone under the conditions of this study.

[Vibravenös--a report of a multicenter trial (author's transl)]

A multicenter trial was conducted in Austria, Germany Holland and Switzerland. A total of 944 patients were included. They had a variety of diagnoses which required hospital admission and intravenous antibiotic therapy. The majority of patients (86.9 p.c.) started therapy with 200 mg doxycycline on the first day. All patients began therapy with an intravenous administration of doxycycline and most were later switched to an oral formulation. Various parameters of response were examined. Resolution of temperature as well as a decrease in associated pain was recorded. Side effects were usually mild and self limiting and were the reason to stop therapy in 1.2 p.c. of the patients. Early improvement was noted in the majority of the diagnostic categories. In 11 p.c. of the cases the response was not indicated or a poor response was noted but overall 89 p.c. of the patients responded to therapy. Doxycycline can be considered a truly useful hospital antibiotic in both its intravenous and oral forms.