Stimulation of cholecystokinin-A receptors with GI181771X does not cause weight loss in overweight or obese patients

Cholecystokinin (CCK) decreases meal size through activation of CCK-A receptors on vagal afferents. We tested the hypothesis that the selective CCK-A agonist GI181771X induces weight loss in obese patients. Patients with body mass index > or = 30 or > or = 27 kg/m2 with concomitant risk factors were randomized to 24-week, double-blind treatment with different GI181771X doses or matching placebo together with a hypocaloric diet. The primary efficacy end point was the absolute change in body weight. To monitor pancreatic and gallbladder effects, patients underwent abdominal ultrasound and magnetic resonance imaging before and after treatment. We randomized 701 patients to double-blind treatment. GI181771X did not reduce body weight and had no effect on waist circumference or other cardiometabolic risk markers. Gastrointestinal side effects were more common with GI181771X than with placebo treatment, whereas hepatobiliary or pancreatic abnormalities did not occur. CCK-A by itself does not have a central role in long-term energy balance.

Randomized trial showing efficacy and safety of twice-daily remogliflozin etabonate for the treatment of type 2 diabetes

We compared the efficacy of twice-daily doses of remogliflozin etabonate (RE) and once-daily pioglitazone with placebo for reduction in glycated haemoglobin (HbA1c) concentration. In this 12-week, double-blind, randomized, active- and placebo-controlled trial, 336 treatment-naïve subjects with type 2 diabetes and an HbA1c of 7.0-9.5% (53-80 mmol/mol) were randomized to RE (50, 100, 250, 500 or 1000 mg twice daily), matching placebo or 30 mg pioglitazone once daily. The primary endpoint was change in HbA1c from baseline. Other endpoints included changes in body weight, lipid levels, safety and tolerability. RE produced a decreasing dose response in HbA1c at week 12 (p < 0.001), with reductions in HbA1c versus placebo ranging from 0.64 to 1.07% (p < 0.001). Statistically significant reductions in body weight for RE compared with placebo were also observed. Twice-daily RE resulted in a dose-ordered improvement in glycaemic control and was generally well tolerated.

Randomized efficacy and safety trial of once-daily remogliflozin etabonate for the treatment of type 2 diabetes

The sodium-dependent glucose transporter 2 (SGLT2) inhibitor remogliflozin etabonate (RE) was evaluated in a 12-week, double-blind, randomized, placebo- and active-controlled, parallel-group study. A total of 252 newly diagnosed and drug-naïve people with type 2 diabetes and glycated haemoglobin (HbA1c) concentrations of 7.0-≤9.5% (53-80 mmol/mol) were recruited. Participants were randomized to RE (100, 250, 500 or 1000 mg once daily or 250 mg twice daily), placebo or 30 mg pioglitazone once daily. The primary endpoint was change in HbA1c concentration from baseline. Secondary endpoints included changes in fasting plasma glucose, body weight and lipid profiles, safety and tolerability. We observed a statistically significant trend in the RE dose-response relationship for change from baseline in HbA1c at week 12 (p < 0.047). RE was generally well tolerated and no effects on LDL cholesterol were observed.

The Safety of Ranitidine Bismuth Citrate in Controlled Clinical Studies

Ranitidine bismuth citrate (Pylorid, Tritec) is a novel drug which heals peptic ulcers and when co-prescribed with either clarithromycin or amoxycillin eradicatesHelicobacter pylori. In controlled clinical studies it was well-tolerated when given alone or when co-prescribed with either antibiotic. Data from 20 clinical studies are reported in this analysis of safety with almost 5000 patients having received ranitidine bismuth citrate (200, 400, or 800 mg twice daily). The incidence of adverse events reported with this new drug, either alone or with an antibiotic, was not different from or lower than in patients given placebo and was independent of the dose of ranitidine bismuth citrate tested. Most commonly reported events (>1% of patients) were upper respiratory tract infection, constipation, diarrhoea, nausea and vomiting, dizziness, and headache, the latter being the only event reported by >2% of patients who received ranitidine bismuth citrate alone. Adverse events considered by the clinical investigator to be adverse reactions occurred with a similar frequency amongst patients given ranitidine bismuth citrate (8%), ranitidine hydrochloride (6%), or placebo (6%). The incidence of adverse reactions was greater when co-prescribed with amoxycillin (11%) or clarithromycin (20%) although it was not different from that noted with the antibiotics alone. Serious adverse events were reported in similar proportions of patients given placebo, ranitidine bismuth citrate alone or with an antibiotic, and ranitidine hydrochloride (range: <1-2%). The safety profile of ranitidine bismuth citrate was thus comparable to that of ranitidine hydrochloride (Zantac), a drug with a well-established record of safety in clinical use.

GR122311X (ranitidine bismuth citrate), a new drug for the treatment of duodenal ulcer

BACKGROUND

Ranitidine bismuth citrate (GR122311X) is a new drug which offers potential benefits in healing duodenal ulcers and prevention of relapse.

METHODS

This randomized, multi-centre double-blind study of 1620 patients compared the effect of 4 weeks of treatment with GR122311X 200 mg b.d. (n = 401), 400 mg b.d. (n = 404) or 800 mg b.d. (n = 404) or ranitidine hydrochloride 150 mg b.d. (n = 411) on the rates of duodenal ulcer healing and of overall success (ulcers healed and remaining ulcer free in the 24-week follow-up phase).

RESULTS

All four treatments were equally effective at ulcer healing (79%, 85%, 84% and 81% of patients, respectively). GR122311X 400 mg b.d. (38%) and 800 mg b.d. (37%) were significantly more effective than ranitidine hydrochloride 150 mg b.d. (32%) with respect to overall success (P = 0.050 and P = 0.030, respectively) but there was no difference with GR122311X 200 mg b.d. (31%). GR122311X caused effective, dose-related suppression of H. pylori (47%, 61% and 74%); H. pylori eradication rates were 18%, 21% and 22%. GR122311X was safe and well tolerated, with an adverse event profile similar to that of ranitidine hydrochloride 150 mg b.d. Median week 4 trough plasma bismuth levels were 1.3 ng/mL, 2.3 ng/mL and 3.3 ng/mL with GR122311X 200 mg b.d., 400 mg b.d. and 800 mg b.d. respectively. No individual plasma bismuth concentrations were of clinical concern.

CONCLUSIONS

GR122311X is a safe and effective ulcer healing drug, and provides a platform on which anti-H. pylori therapy can be based.

Effects of single doses of the converting enzyme inhibitor cilazapril in normal volunteers

The new converting enzyme inhibitor cilazapril, or RO 31-2848, was evaluated in 14 healthy male volunteers. In a pilot study in two subjects, the inhibiting capacity of single oral doses of 5 and 10 mg on the pressure and heart rate response to exogenous angiotensin I was assessed. Both doses reduced the blood pressure response to angiotensin I to 10% of control within 45 min and for the 4 h tested. In the main study, 12 volunteers each received two single oral doses of cilazapril at a 2-week interval, and plasma converting enzyme and renin activity, blood angiotensin I, plasma immunoreactive angiotensin II and aldosterone were measured serially. Single doses of 1.25, 2.5, 5, and 10 mg of cilazapril were tested in groups of six subjects each. All doses inhibited plasma converting enzyme activity by 90% for at least 8 h and induced the expected pattern of changes of the renin-angiotensin-aldosterone system. Only slight dose-dependent variations in the effect were observed. Basic heart rate and blood pressure were not altered by any of the doses, which all were well tolerated. These data suggest that cilazapril is a very potent and long-acting new converting enzyme inhibitor.

Pharmacokinetics of the converting enzyme inhibitor cilazapril in normal volunteers and the relationship to enzyme inhibition: development of a mathematical model

The pharmacokinetics of the new converting enzyme inhibitor cilazapril were investigated in 12 healthy male volunteers. Single oral doses of 1.25, 2.5, 5, and 10 mg of cilazapril were tested in groups of six subjects, each of whom received two different doses. A 2-week interval was allowed between treatments. Plasma levels of cilazaprilat, the active form of cilazapril, were measured for up to 3 days after drug administration. Peak plasma levels and 24-h areas under the curve (AUCs) were almost directly proportional to dose, and the elimination half-life (t1/2) during the first 8 h after dosing was 1.5 h. From 24 h on, there was a prolonged terminal phase with a t1/2 of approximately 50 h, and there was only slight dose-dependency during this phase. These data suggest that the pharmacokinetics of cilazapril are nonlinear. A physiologically realistic model based on saturable binding to converting enzyme was developed to account both for the drug kinetics and for the relationship of the kinetics to the dynamics of plasma converting enzyme inhibition. A number of conclusions relevant to the therapeutic application of cilazapril in hypertension are drawn from the data and from the pharmacokinetic-pharmacodynamic model.

Repeated administration of the converting enzyme inhibitor cilazapril to normal volunteers

Cilazapril 1.25 and 5.0 mg p.o. q.d. was administered in double-blind fashion to two groups of six normal volunteers on 8 consecutive days. Blood pressure, heart rate, and plasma converting enzyme activity were measured each day prior to drug administration and up to 72 h after the last dose. Plasma renin activity, blood angiotensin I, plasma angiotensin II, and aldosterone as well as plasma cilazaprilat levels were determined on the first and the last day of active treatment at times 0, 4, and 24 h. The drug was very well tolerated by all volunteers. At 4 h postdrug, plasma converting enzyme activity was reduced in dose-dependent fashion on the first and the eighth day; plasma cilazaprilat levels were also clearly dose dependent. Nevertheless, 24 h postdrug cilazaprilat levels were similar on the first and last day of drug administration, and plasma converting enzyme activity was also stable throughout the 8 days. The various components of the renin-angiotensin system responded in the usual fashion. These results provide strong evidence that cilazapril is a very potent and highly effective converting enzyme inhibitor. Doses well below 5 mg/day will probably suffice for therapeutic efficacy. These data also confirm the hypothesis formulated in the preceding article, i.e., that there is no accumulation of the drug with repeated administration despite its long pharmacological half-life (t1/2).