Inter-Company Collaboration Combination Trials. Clinical Trial Subcommittee of the Inter-Company Collaboration for AIDS Drug Development.

The Inter-Company Collaboration for AIDS Drug Development (ICC) represents a collaborative effort among member companies to facilitate the conduct of clinical trials on AIDS drugs. One of the goals of the ICC is to expedite the development of combination antiretroviral therapy through data and compound sharing. Recently, the ICC formed a consensus master protocol to evaluate rapidly the safety and efficacy of triple-drug combinations of antiretroviral therapy for treatment of HIV-infected patients. This concept builds upon historical work with combination chemotherapy that resulted in treatments to successfully control chronic immunosuppressive, infectious or malignant diseases, such as tuberculosis, leprosy, childhood acute lymphoblastic leukemia, and Hodgkin's lymphoma. Because of limitations on potency and the continuing emergence of drug resistance seen with use of currently available antiretroviral agents in monotherapy and two-drug combination regimens, triple-combination regimens should represent a more promising approach to maximize antiviral activity, maintain long-term efficacy, and reduce the incidence of drug resistance. The ICC master protocol is a randomized, controlled, double-blind study with a treatment duration of 52 weeks. Patients eligible to enroll in this study must have documented HIV infection, with CD4 counts between 200 and 500 cells/mm3, and no history of antiretroviral therapy. The first four triple-drug combinations will be evaluated in two trials. These regimens have been selected based on encouraging data from laboratory and clinical studies. Each ICC trial will consist of three arms, with 75 patients per arm. Protocol ICC 001 will include AZT + zalcitabine (ddC) + saquinavir, AZT + ddC + nevirapine, and AZT + ddC as the control arm.(ABSTRACT TRUNCATED AT 250 WORDS)

Zalcitabine compared with zidovudine in patients with advanced HIV-1 infection who received previous zidovudine therapy.

OBJECTIVE: To evaluate the safety and efficacy of zalcitabine (also known as dideoxycytidine [ddC]) in patients with advanced human immunodeficiency virus (HIV) infection. DESIGN: Open-label, randomized study. SETTING: AIDS Clinical Trials Units, university-affiliated medical centers, and private practice groups. PATIENTS: Patients with the acquired immunodeficiency syndrome (AIDS) or advanced AIDS-related complex who had tolerated zidovudine for 48 weeks or more. INTERVENTION: Fifty-nine patients received zidovudine (500 to 1200 mg/d) and 52 patients received zalcitabine (2.25 mg/d). MEASUREMENTS: The primary end points were survival and time to an AIDS-defining event or death. RESULTS: Because significantly more patients withdrew from zidovudine therapy, the median duration of treatment was greater in the zalcitabine group than in the zidovudine group (279.0 days compared with 174.5 days; P = 0.001). The estimated 12-month, event-free probabilities were 53% for the zalcitabine group and 57% for the zidovudine group (relative risk, 1.02; 95% CI, 0.5 to 2.2). The estimated 12-month survival rates were 81% for the zalcitabine group and 75% for the zidovudine group (relative risk, 1.39; CI, 0.5 to 3.8). The rate of decline in CD4 lymphocyte counts was significantly slower in the zalcitabine group than in the zidovudine group (-0.08 cells/day compared with -0.17 cells/day). Patients in the zalcitabine group had gained an average of 0.5 kg at week 20 and 0.4 kg at week 24, whereas patients in the zidovudine group had lost an average of 1.8 kg at week 20 and 2.4 kg at week 24 (P = 0.04 and P = 0.05, respectively). Moderate to severe peripheral neuropathy and ulcerative stomatitis occurred in 10 and 9 patients, respectively, in the zalcitabine group. CONCLUSIONS: The sample size for this study was smaller than planned, and no differences in survival and clinical end points were found. Slower rates of decline in CD4 lymphocyte counts and weight, however, were noted for the zalcitabine group.

The effect of trimoprostil (trimethyldesoxy prostaglandin E2) on the intrauterine pressure in women.

Prostaglandin E2 is uterotonic. Trimoprostil, a prostaglandin E2 analog, is a gastric antisecretory and cytoprotective agent. The effects of single doses of 0, 0.125, 0.75, and 3.0 mg trimoprostil on intrauterine pressure were measured in a double-blind, crossover study in eight surgically sterile women. The 3 mg dose was not tolerated because of abdominal cramps. The other doses caused a dose-related increase in resting uterine tone and peak pressure with peak effect occurring between 30 and 60 minutes after administration with a duration of about 120 minutes. No effects on the frequency of uterine contractions occurred. Peak mean tone increased from 11.0 to 71.2 mm Hg (p less than 0.01) and peak pressure from 24.6 to 125.1 mm Hg (p less than 0.01) after placebo compared with the 1.5 mg dose. Adverse reactions included abdominal pain that correlated with an increase in intrauterine pressure and tone.

Changes in lipid metabolism in diet-induced obesity.

Mature male Sprague-Dawley rats fed a powdered Purina Chow diet containing corn oil and condensed milk (CM) were compared to rats fed a Purina Chow diet (control). CM rats gained more weight and consumed more calories over a 73-day period than the control rats. The increased weight gain and body fat in CM rats was accompanied by increased cell number in retroperitoneal and inguinal but not epididymal fat pads while cell size was unchanged in all three pads. After obesity had developed there was an increase in insulin levels, lipolysis, hepatic fatty acid synthesis, and fatty acid oxidation. While CM rats demonstrated hyperinsulinemia and hyperglycerolemia, they maintained normal glucagon and glucose levels. They demonstrated higher rates of fatty acid synthesis in isolated hepatocytes but not in vivo, suggesting that a greater potential for fatty acid synthesis in CM rats was masked in vivo by the inhibitory action of dietary lipids. Beta-oxidation of (1-14C) palmitate in vivo and in vitro, and in vivo ketogenesis were greater in CM than in chow fed rats. These studies demonstrate that, after the development of obesity, CM rats, like genetically obese Zucker rats, are hyperinsulinemic and have elevated levels of fatty acid synthesis. However, unlike obese Zucker rats, CM rats displayed an increase in beta-oxidation. These studies suggest that increased insulin levels and hepatic fatty acid synthesis may contribute to dietary obesity (as they do to genetic obesity), whereas increased fatty acid oxidation in dietary obesity may be a compensatory response to maintain a lower body weight.