European study on dose-response relationship of acarbose as a first-line drug in non-insulin-dependent diabetes mellitus: efficacy and safety of low and high doses

The aim of this double-blind, placebo-controlled, multinational, five-arm study was to investigate the dose-response relationship of acarbose as a first-line drug in the treatment of type 2 diabetes (non-insulin dependent) over a range of minimal and maximal doses according to the European recommendations. The study included 495 patients from 7 countries who were insufficiently controlled with diet alone (glycosylated haemoglobin HbA1C 6.5%-9%). Acarbose, 25, 50, 100 or 200 mg t.i.d., or placebo t.i.d. was given for 24 weeks. Even a low dosage of 25 mg t.i.d. acarbose reduced fasting and postprandial blood glucose levels (1 h postprandial -11.6%; 2 h postprandial -11.3%). Acarbose in a dosage of 200 mg t.i.d. had the greatest effect on these parameters. In the placebo group the mean 2 h postprandial area under the curve (AUC) value for blood glucose was 22.6 mmol/l after 24 weeks' therapy. The mean 2 h postprandial AUC values in the patients given acarbose at doses of 25, 50, 100 and 200 mg t.i.d. were found to be 21.2, 19.6, 20.3 and 18.5 mmol/l, respectively. The corresponding HbA1C values for the placebo and acarbose groups were 7.83%, 7.37%, 7.08%, 6.98% and 6.79%. Interestingly, there was a plateau of blood glucose level at a dosage of 50-100 mg t.i.d. The frequency of flatulence decreased with the duration of drug therapy, but we could not find a linear relationship between doses of acarbose and the gastrointestinal side effects. Less than 3% of patients stopped tablet intake due to adverse events.

[Stomach tolerance of acetylsalicylic acid by addition of calcium carbonate. A study of a 2-treatment/3-period cross-over design]

18 male volunteers (age 24 +/- 4 years; Broca index 0.94 +/- 0.08; mean +/- SD) underwent six upper endoscopies (three control and three test investigations) in a single blind two treatments-crossover designed study which evaluated the effect of buffering on aspirin-induced (one single oral dose of 0.5 g aspirin to fasted subjects) gastroduodenal mucosal injury. All subjects had a normal endoscopy prior to applications of 0.5 g plain aspirin (group A; swallowed) or 0.5 g aspirin + 0.3 g calcium carbonate (group B; chewed before swallowing). The sequence groups were A-B-B (n = 9) or B-A-A (n = 9). In advance fo the performed tests a washout period of six days was chosen. Endoscopies were performed two hours after ingestion of the respective tablets. The appearance of corpus, antrum, and duodenum was scored. Biopsies were taken for histological examinations. 15 volunteers experienced no gastrointestinal side effects. Three complained short-lasting gastric burning (two of group A, one of group B). In both treatment groups no significant lesions of the duodenum were found. Buffering significantly (p less than 0.0005) reduced mucosal injuries which occurred mainly as submucosal hemorrhage but without histological alterations of the mucosal architecture after aspirin ingestion. These findings suggest that oral administration of calcium carbonate buffered, chewable aspirin tablets is less harmful to the gastric mucosa than plain aspirin.

The effect of new alpha-glucosidase inhibitors (BAY m 1099 and BAY o 1248) on meal-stimulated increases in glucose and insulin levels in man

To confirm findings obtained from animal experiments demonstrating the metabolic effect of two new glucosidase inhibitors, 7 single blind cross-over studies with 42 healthy male volunteers were performed. In each group 6 subjects received 25, 50, 100 and 200 mg BAY m 1099 and 10, 20, and 40 mg BAY o 1248 or placebo with a standardized breakfast. Blood glucose and serum insulin were measured in venous blood before and 30, 60, 90, 120 and 180 min after each of 3 meals. ECG, blood pressure, body weight, monitor ECG and haematological and clinico-chemical parameters were also examined. The postprandial increase in blood glucose and serum insulin after breakfast were significantly and dose-dependently reduced by BAY m 1099. 10 and 20 mg BAY o 1248 not only reduced the increases in blood glucose and serum insulin after breakfast, but also after lunch (10 mg). 40 mg BAY o 1248 prevented the postprandial increase in both metabolic parameters after breakfast (p less than 0.05), an effect which was sustained after lunch. Intestinal problems occurred (flatulence, meteorism, diarrhoea) in 25 of 42 volunteers. Objective tolerability was good. The results of these first clinical pharmacological studies with two new glucosidase inhibitors justify studies on patients with diabetes mellitus.

Long-term treatment in diabetics with acarbose, a glucosidase inhibitor: efficacy, tolerability and effect on GI hormones

12 months therapy with acarbose in 143 type I and type II patients markedly improved the metabolic control, assessed by fasting and postprandial blood glucose determination. During 5 year acarbose treatment GIP levels were decreased and enteroglucagon levels were elevated. After withdrawal of the drug for one week GIP levels increased and enteroglucagon concentrations fell. Thus, GI-hormone changes were reversible after discontinuation of acarbose. Tolerability of acarbose was good and clinical chemistry and haematology parameters showed no changes after 1-5 years acarbose therapy. Approximately 60% of the patients had intestinal symptoms which subsided again for most patients after 1-4 weeks therapy with acarbose. Body weight remained unchanged. The glucosidase inhibitor acarbose is a new effective and safe therapeutic concept in the treatment of diabetes mellitus.

Evaluation of amitrole (aminotriazole) for potential carcinogenicity in orally dosed rats, mice, and golden hamsters

Amitrole was evaluated for carcinogenic potential in lifespan studies on Wistar rats, NMRI mice, and golden hamsters. At the start of the studies the animals were 6 weeks old. Amitrole was administered, mixed with pulverized chow, at dietary concentrations of 0, 1, 10, and 100 micrograms/g (ppm). Each treated group and control group consisted of 75 male and 75 female rats and mice and of 76 male and 76 female golden hamsters. Additional animals were used to evaluate the functional state of the thyroid. Somewhat lower body weights, slightly reduced survival times, and transient effects on thyroid function were observed in golden hamsters at 100 ppm. In mice, a slight increase in pituitary gland hyperemias was seen at 100 ppm; also an effect on thyroid function usually occurred at the same concentration. In rats, a very large number of cystic dilatations of follicles in the thyroid at 100 ppm and a dose-unrelated increase in hemorrhages and hyperemias in the pituitary gland were indicative of an effect of amitrole on these organs. The strongest effect of amitrole on thyroid function, as compared to golden hamsters and mice, was seen in rats at 100 ppm. At this concentration a highly increased number of thyroid and pituitary gland tumors was observed in rats. In golden hamsters and mice, no tumor induction was seen.

The effects of the alpha-glucosidase inhibitor BAY g 5421 (Acarbose) on postprandial blood glucose, serum insulin, and triglyceride levels: dose-time-response relationships in man

In a double-blind quadruple cross-over study the effect of a new alpha-glucosidase inhibitor (BAY g 5421) on postprandial blood glucose, serum insulin, and serum triglyceride increases was tested in 24 male healthy volunteers. They received before a standardized breakfast 50, 100, or 200 mg of BAY g 5421 or a placebo per os. The dose-time-response relationships were calculated and the drug tolerance was assessed. There was a statistically significant inhibition of the postprandial increases of the blood glucose, serum insulin, and triglyceride values. Further analysis showed no dose-dependent effect of the drug on the blood glucose values, whereas the serum insulin and triglyceride values were affected in a dose-dependent fashion. The maximal inhibitory effect on the serum insulin levels occurred 69 min after breakfast and on the serum triglyceride levels 104 min after breakfast. One hundred and 200 mg of BAY g 5421 were equally inhibitory-effective on the serum insulin levels, whereas the highest dose used was markedly more effective on serum triglyceride values than lower doses. Based on these results, a dosage of 100--200 mg of BAY g 5421/meal is recommended for clinical trials in metabolic diseases.

The effects of the alpha-glucosidase inhibitor BAY g 5421 (Acarbose) on meal-stimulated elevations of circulating glucose, insulin, and triglyceride levels in man

In blind studies the effects of a new alpha-glucosidase inhibitor (BAY g 5421) were tested in normal weight and overweight male volunteers after oral application of 75, 150, or 300 mg of BAY g 5421 or placebo per os before three standardized main meals of one day. Before and three hours after each meal blood glucose, serum insulin, and serum triglyceride levels were determined. In addition, safety studies were performed. BAY g 5421 induced a statistically significant, in part dose-dependent inhibition of the postprandial increase of blood glucose- and serum insulin levels. The reduction of the postprandial increase of serum triglyceride levels was variable. Routine blood chemistry and hematology tests have revealed no adverse side effects; but the application of the drug was frequently associated with intestinal effects, such as flatulence and diarrhea, which were substrate (carbohydrate) and, in part, dose-dependent.

Preliminary clinical trials with praziquantel in Schistosoma japonicum infections in the Philippines

Praziquantel, a new antischistosomal compound, was tested for tolerance and efficacy against placebo in two double-blind clinical trials in Philippine patients infected with Schistosoma japonicum.The compound was given orally at a dose of 3 x 20 mg/kg at intervals of 4 hours to a total of 82 patients-some without advanced disease and some with hepatosplenic involvement. A total of 43 patients received placebo. In a single-blind trial, 42 patients were given a single oral dose of 50 mg/kg. Monitoring of vital organ functions included comprehensive laboratory tests and serial electrocardiograms. In 38 patients with hepatosplenic involvement due to advanced stages of infection, serial electroencephalograms were additionally recorded. No toxic effects were observed in any of these examinations.Undesirable side effects occurred in 53% of the patients given 3 x 20 mg/kg and in 70% after a dose of 1 x 50 mg/kg. They consisted mainly of abdominal discomfort, fever, sweating, and occasionally giddiness, but in general were transient and mild. At 6 months post-treatment, 60 of 75 patients treated with 3 x 20 mg/kg and 29 of 41 treated with 1 x 50 mg/kg were completely negative for eggs. At 12 months post-treatment, 25 of 33 and 14 of 26 patients in the two treatment groups were cured. Thus the divided dosage gave a superior therapeutic result. Praziquantel proved to be free of major toxicity, and was well tolerated, highly effective, and easy to administer. Confirmation of results in extended trials may soon permit large-scale treatment.

Double-blind studies of tolerance to praziquantel in Japanese patients with Schistosoma japonicum infections

The first clinical trials of praziquantel against Schistosoma japonicum infections in Japan were planned to assess tolerance only. Three double-blind studies against placebo involving a total of 51 patients were conducted with dosages of praziquantel of 1 x 20 mg/kg body weight, 2 x 20 mg/kg, 3 x 20 mg/kg given on one day.The frequency of unwanted side effects was higher in the group of patients given praziquantel at a dose of 3 x 20 mg/kg than in all other drug- or placebo-treated patients. In general, the side effects, which included drowsiness, headache, lumbago, abdominal fullness, or epigastric discomfort, lasted for several hours but disappeared spontaneously. The results of laboratory tests showed no significant changes caused by treatment.The overall assessment showed excellent or good tolerance in all patients treated with praziquantel at the lower dose levels. In those given 3 x 20 mg/kg, tolerance was excellent in 1 of 12 patients, good in 9, and fair in 2, whereas the respective placebo-treated group showed excellent tolerance in 3 of 12, good in 7, and fair in 2.