[Efficacy and safety of pristinamycin vs amoxicillin in community acquired pneumonia in adults]. / Essai comparatif de l'efficacité et de la tolérance de la pristinamycine vs amoxicilline dans le traitement des pneumonies aiguës communautaires de l'adulte.

STUDY OBJECTIVE: Evaluation of efficacy and safety of pristinamycin (PRI), compared with amoxicillin (AMX), both at 3 g daily for 7 to 10 days in adults with community-acquired pneumonia (CAP). PATIENTS AND METHODS: Multinational, randomized, double blind, double dummy clinical trial of non-inferiority was conducted in 399 patients with a CAP. RESULTS: At inclusion, the mean age was 47.8+/-18.3 years, 24.3% patients were 65 or older. The Fine score was < or =III in 85.4% patients. The bacterial etiology was documented in 34.8% of patients: Streptococcus pneumoniae (48.1%), Mycoplasma pneumoniae (18.6%), Haemophilus influenzae (14.7%), Chlamydia pneumoniae (13.2%), Legionella pneumophila (9.3%). In the clinical per-protocol population, the clinical success rate was 87.6% in each group: 149/170 patients (PRI) and 148/169 (AMX); The 95% confidence interval was [-6.61%; 7.23%]. In modified intend to treat population, the clinical success rate was 79.9% (151/189) in the PRI group and 83.0% (151/182) in the AMX group [CI 95% (-10.87%; 4.69%)]. A satisfactory bacteriological response was observed in 82.3% (51/62) of PRI patients and 88.1% (59/67) of AMX patients. Treatment related adverse events occurred similarly in both groups according to the expected tolerance profile of the two drugs. No serious adverse events in both groups were related to the study drugs. CONCLUSIONS: In this study, PRI 3 g daily was clinically as effective and well tolerated as AMX 3 g daily, for 7 to 10 days, in PPc, in the treatment of bacterial community-acquired pneumonia.

[Treatment of exacerbations of chronic obstructive pulmonary disease with pristinamycin]. / Traitement des exacerbations de broncho-pneumopathie chronique obstructive (BPCO) par la pristinamycine.

BACKGROUND: Pristinamycin is a bactericidal antibiotic whose spectrum covers the main respiratory pathogens including S. pneumoniae poorly sensitive to penicillin. It has not yet been evaluated in short course treatment of acute exacerbations of chronic obstructive bronchitis (AECB). METHODS: 476 patients suffering from an AECB were randomised to either a short course of pristinamycin, 3 G daily for 4 days, or conventional treatment with co-amoxiclav (AAC) 2G daily for 8 days. The duration of follow-up was 6 months. RESULTS: The clinical success rate at 21 days was the same in both groups at 87.2% and 87.9%, CI95% [-7.0%, 6.0%], in the protocol population (FEV1<80%). Among the 120 patients in whom a bacterial pathogen was isolated at the time of inclusion a satisfactory bacteriological response was obtained in 84.6% of the PRI patients against 78.2% of the AAC patients. The time to relapse was comparable with a relapse rate of 25% reached in 128 days in the PRI group and 125 days in the AAC group. Treatment related side effects occurred in 9.2% of the PRI group and in 10.6% of the AAC group. CONCLUSION: Pristinamycin 3 G daily for 4 days is as effective and well tolerated as co-amoxiclav 2G daily for 8 days in the treatment of AECB.

Comparison of lansoprazole with omeprazole on 24-hour intragastric pH, acid secretion and serum gastrin in healthy volunteers.

BACKGROUND: Lansoprazole and omeprazole are proton pump inhibitors which both strongly inhibit acid secretion, resulting in a significant increase in serum gastrin levels. However, no direct comparison of recommended doses (20 mg for omeprazole and 30 mg for lansoprazole) has been reported so far. Our aims were to compare the effects of omeprazole 20 mg/day and lansoprazole 30 mg/day on intragastric acidity and serum gastrin concentration in 12 healthy volunteers. METHODS: The study was double-blind, randomized and placebo-controlled with a cross-over design. On the seventh day of each period, 24-hour intragastric pH was measured using a combined glass electrode placed in the proximal stomach. The last morning dose of each regimen was taken at the end of 24-hour pH monitoring; acid output and serum gastrin concentrations were then studied in the fasting state and after stimulation with pentagastrin (maximal acid output) and a meal (post-prandial gastrin response). RESULTS: Compared to placebo, both drug regimens induced a sustained increase of 24-hour intragastric pH and significantly decreased basal and pentagastrin-stimulated acid secretion. Lansoprazole 30 mg was slightly more effective than omeprazole 20 mg in terms of time spent above pH 3 (P < 0.05). Accordingly postprandial gastrin concentrations rose slightly more after lansoprazole than after omeprazole. All other differences were insignificant. CONCLUSIONS: Both lansoprazole 30 mg and omeprazole 20 mg induce potent and long-lasting acid inhibition, with few minor differences when the two proton pump inhibitors are used at standard doses.

Single and multiple dose pharmacokinetics of lansoprazole in elderly subjects.

Plasma concentrations of lansoprazole and of its sulphone, sulphide and 5-hydroxylated metabolites were determined after oral administration of a single 30 mg dose and after 7 days of treatment with a daily 30 mg dose in 12 elderly subjects (mean age 83 years). Results after a single dose were compared with those from a historical control group of 18 young subjects (mean age 23 years). Mean values of AUC after single dose were 2668 ng ml(-1) h in the young subjects and 5216 ng ml(-1) h in the elderly (P < 0.05). Mean t 1/2z values in young and elderly subjects were 1.4 h and 2.9 h, respectively (P < 0.001). Plasma concentrations of the metabolites were similar in both groups. However, the hydroxylated metabolite of the sulphone was detected only in elderly subjects. Steady state plasma concentrations of lansoprazole were reached after 3 days of dosing with lansoprazole. The accumulation ratio was 1.31 in the elderly subjects.

Pharmacokinetics of lansoprazole in patients with renal or liver disease of varying severity.

The pharmacokinetics of lansoprazole (L) after a single oral dose of 30 mg was determined in 18 healthy volunteers, 17 renal failure patients and 24 hepatic failure patients; 8 hepatitis and 16 with compensated (CC) or uncompensated (UCC) cirrhosis. In renal failure, the absorption of L was unchanged, its half-life being similar to that in healthy subjects; a small change seen in mild renal failure patients (creatinine clearance between 40 and 60 ml/min) was attributed to the age of the patients. Urinary elimination, essentially as metabolites of lansoprazole, was decreased, in relation to the degree of renal impairment. In hepatitis patients, the AUC and t1/2 of L were doubled, without any change in Cmax. In cirrhotics tmax was prolonged, the AUC was increased (P < 0.001) and there was prolongation of t1/2 (6.1 h in CC and 7.2 h in UCC compared to 1.4 h in healthy subjects). These changes resulted from a decrease in the clearance of L. There was also an increase in its sulphone metabolite (Cmax, Rm) and a decrease in the hydroxylated metabolite (Cmax, Rm) in relation to the degree of liver disease, and reflecting a decrease in hydroxylation and biliary elimination. Thus, renal failure had no effect on the pharmacokinetics of L, but severe hepatic failure caused marked changes. A repeated dosing study would be necessary to evaluate the repercussions of the possible accumulation in cirrhotic patients.

Dose ranging study of lansoprazole, a new proton pump inhibitor, in patients with high gastric acid secretion.

The effects of single doses and of 7 days of lansoprazole 10, 20 and 30 mg PO versus placebo on gastric acid secretion have been evaluated in 8 patients with high gastric acid secretion. The double blind crossover period was followed by a simple blind 7 days on placebo to detect any rebound phenomenon. After the first dose lansoprazole did not modify basal acid output (BAO) but it significantly and dose dependently inhibited peak acid output (PAO) and increased the time during which nocturnal intragastric pH was greater than 3. After 7 days of treatment the same significant, dose-dependent suppression of gastric acid was found, but BAO was also blocked. One week after cessation of lansoprazole administration no rebound increase in gastric acid-secretion was observed. The plasma gastrin concentration remained unchanged throughout the study.

Enhancement of propoxyphene bioavailability by ethanol. Relation to psychomotor and cognitive function in healthy volunteers.

The interaction between a single oral dose of 130 mg propoxyphene and 0.5 g/kg body weight ethanol was investigated in 12 healthy male volunteers by 9 objective performance tests, 8 visual analogue self-rating scales and the measurement of plasma propoxyphene, norpropoxyphene and ethanol concentrations, using a double-blind threeway crossover design. Volunteers were each given one of three treatments, propoxyphene + ethanol, placebo + ethanol and propoxyphene alone, separated by a two week interval. The performance tests were completed before and 1.25 and 4 h after drug intake, and the self-rating scales before and 1.25, 4 and 10 h after it. Ethanol was shown to enhance the bioavailability of propoxyphene by 25% probably by reducing its first-pass metabolism. However, despite this pharmacokinetic effect no pharmacodynamic interaction was found. Subjective ratings disclosed that the effect of ethanol on physical and mental sedation predominated over the effects of propoxyphene.

The effect of food and antacids on lansoprazole absorption and disposition.

Bioavailability of lansoprazole, a new gastric proton pump inhibitor, was investigated in 12 healthy subjects. Each subject received in random order, lansoprazole (30 mg) alone or associated with standard meal or with antacids (aluminium and magnesium hydroxides) or one hour later than antacids. Lansoprazole and metabolite (sulfone (AG 1813), sulfide (AG 1777) and hydroxylated (AG 1908) metabolites) plasma concentrations were determined using a specific high pressure liquid chromatographic assay procedure, with a limit of detection of 2 ng/ml. The time to peak was significantly later with food (p less than 0.001) and its magnitude was significantly decreased (600 +/- 330 ng/ml vs 1151 +/- 344 ng/ml, p less than 0.001). The bioavailability of lansoprazole was significantly decreased by food, about 27%, (p less than 0.05) and slightly decreased by concomitant administration of antacids (NS), the effect was more pronounced in male subjects (p less than 0.05). Lansoprazole is presented as an enteric-coated granules, the concomitant administration of antacids, increasing the gastric pH, increased the absorption rate of lansoprazole. When antacids were administered one hour before lansoprazole, no effect was observed on lansoprazole bioavailability. This study showed that lansoprazole must be administered in fasting state and not simultaneously with antacids.