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Objective BETA was designed to evaluate the overall effectiveness of aripiprazole in patients with schizophrenia or schizoaffective disorder treated in a general psychiatry outpatient practice setting. Methods In this 8-week, multicenter, open-label study, 1599 outpatients with schizophrenia or schizoaffective disorder were randomly assigned to receive either aripiprazole (n = 1295) or another antipsychotic medication (safety control [SC] group; n = 304). Aripiprazole was initiated at 15 mg/d with the option to adjust between 10–30 mg/d. The SC medication was specifically selected for each patient by the clinician and dosed according to prescribing guidelines for that medication. The primary effectiveness measure was the Clinical Global Impression–Improvement (CGI–I) score of the aripiprazole group at study end point. Secondary measures included response rates and preference of medicine (POM) ratings by patients and caregivers. Results Sixty-five percent of aripiprazole patients completed the study. The mean aripiprazole dose at end point was 19.9 mg/d, with approximately 39% of patients starting and remaining at 15 mg/d. At end point, the mean CGI–I score of 2.77 demonstrated that aripiprazole was minimally to moderately effective; the mean CGI–I score for the SC group was 3.59 indicating minimally effective to no change. Fifty-three percent of aripiprazole patients responded to treatment (CGI–I score of 1 or 2; last-observation-carried-forward [LOCF]), and approximately 71% of patients and caregivers rated aripiprazole as better than the prestudy medication on the POM (LOCF). Incidence and severity of adverse events (AEs) were similar to those reported in double-blind, randomized, placebo-controlled aripiprazole clinical trials. The most frequent AE in the aripiprazole group was insomnia (24%). Conclusions Aripiprazole was effective for the treatment of schizophrenia and schizoaffective disorder in a general psychiatry outpatient practice setting. Overall, aripiprazole was found to be effective by the treating clinician and well accepted by patients and caregivers over the 8-week treatment course.

Glibenclamide is an antagonist of the ATP-modulated K+ channel in cardiac tissue. This study showed glibenclamide to bind to high (0.2 nM) and low (40 nM) affinity binding sites in canine ventricular membranes. Gpp [NH]p significantly altered the binding characteristics of the low affinity site, while those of the high affinity site were unchanged. This indicates independence of the two sites and suggests the low affinity site may be coupled to a G-binding protein. Although we have identified two [3H]glibenclamide binding sites, the importance of these sites to the cardiac effects of glibenclamide remains to be determined.

The existence of a single or of multiple populations of glibenclamide binding sites is a subject of controversy. In the present study, radioligand binding techniques were employed to determine whether multiple populations of [3H]glibenclamide binding sites exist in pancreatic tumor (insulinoma) cells. Additional studies were performed to further characterize the binding of [3H]glibenclamide to insulinoma and cardiac membranes. [3H]Glibenclamide bound to high (0.1 nM) and low (240 nM) affinity binding sites in insulinoma membranes. The physiological relevance of multiple populations of sites is unknown. The binding of glibenclamide to insulinoma and cardiac membranes was altered by guanine nucleotides and not adenine nucleotides. This suggests glibenclamide binding can be modulated by G-proteins. Glibenclamide binding was also modulated by divalent cations. The divalent cations, Ca2+ and Zn2+, stimulated specific glibenclamide binding to cardiac and insulinoma membranes, while Mg2+ and Mn2+ enhanced cardiac binding only. Moreover, the lowering of pH from 7.4 to 6.5 was found to enhance specific glibenclamide binding. Interestingly, the magnitude of this effect was much larger in cardiac membranes. The specific nature of the regulation of glibenclamide binding by guanine nucleotides, divalent cations and pH remains to be explored.