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K Bragman

Publications and source records attributed to K Bragman.

12 recordsLinked to original sources

Ethics and pharmaceutical medicine -- the full report of the Ethical Issues Committee of the Faculty of Pharmaceutical Medicine of the Royal Colleges of Physicians of the UK.

The practice of pharmaceutical medicine brings with it ethical challenges and dilemmas often very different from those encountered in the practice of clinical medicine. Having established a framework of guiding ethical principles, this report aims to look in some detail at specific areas of possible ethical concern to pharmaceutical physicians, offering practical advice and guidance on good practice. The report covers issues related to pharmaceutical research, including dissemination of research findings, communication with other health professionals and patients and involvement of pharmaceutical physicians and companies in the provision of patient services. The primacy of the interests of patients and the wider public is emphasised, and the possible impact of new developments in pharmaceutical technology is explored. It is hoped that the report will help those working in pharmaceutical medicine and act as a stimulus for wider discussion and debate.

Biomedical Research↗

Guiding Principles for Pharmaceutical Physicians from the Ethical Issues Committee of the Faculty of Pharmaceutical Medicine of the Royal Colleges of Physicians of the UK.

Medical practitioners practising in the field of pharmaceutical medicine, whether in industry, regulatory bodies or an academic environment, are bound by the same ethical standards which apply to all doctors. Their work, however, leads to some very specific ethical considerations which may not be fully explored in ethical codes based in clinical medicine. This document aims to establish some guiding principles which should underpin a working ethical framework for pharmaceutical physicians. It clearly places the protection of patients (and research subjects) and the doctor's duties to wider society ahead of responsibilities to an individual employer while emphasising the importance of adherence to high standards of research, including dissemination of findings. These principles form the basis of a fuller report which offers more specific practical advice on possible ethical conflicts or dilemmas.

Clinical Trials as Topic↗

Emergence of resistant variants of HIV in vivo during monotherapy with the proteinase inhibitor saquinavir.

We examined the phenotypic and genotypic properties of virus from the peripheral blood mononuclear cells (PBMC) and plasma of eight HIV-1-infected asymptomatic patients before and during monotherapy with the proteinase inhibitor saquinavir. Susceptibility of primary isolates to drug was assessed in PBMC culture by deriving IC50 and IC90 values. The observed increases in IC50 and IC90 after approximately one year of therapy with a dosage of 600 mg tds suggests the presence of virus resistant to saquinavir in vivo. The magnitude of this altered susceptibility ranged from three-fold to in one case 100-fold. In two patients a greater than eight-fold decrease in susceptibility to saquinavir was observed. Sequencing of the proteinase genes in viral RNA obtained from patient plasma and/or PBMC was carried out by PCR in parallel with sensitivity testing. In each case between nine and 12 clones were analysed. In the two patients from whom virus had greater than eight-fold reduction in susceptibility, a point mutation was observed in the viral proteinase (Leu90--> Met/Ile). Further mutations were observed at residues 36, 71 and 84 in these subjects. In a third patient, in whom an eight-fold increase in HIV IC50 of saquinavir was observed, no mutations were detected in the proteinase; sequencing of proteinase cleavage sites in viral gag-pol revealed no significant mutations. In no patient was a Gly48-->Val mutation observed, although this has been associated with resistance in vitro. The Leu90-->Met mutation was observed in five subjects, but a greater than eight-fold phenotypic change in antiviral susceptibility was seen in only two of these. Hence, in vivo, the Leu90-->Met but not the Gly48-->Val mutation is necessary, but not sufficient, for phenotypic resistance to saquinavir in HIV.

Adult↗

A randomized controlled trial of a protease inhibitor (saquinavir) in combination with zidovudine in previously untreated patients with advanced HIV infection.

This study assessed the activity and tolerability of an HIV-protease inhibitor, saquinavir, alone or in combination with zidovudine. A total of 92 previously untreated HIV-infected patients with CD4 cell counts < 300 cells/mm3 participated in a parallel, randomized double-blind study. Patients were randomized to receive one of five treatments, each three times a day: 600 mg of saquinavir; 200 mg of zidovudine; 75, 200 or 600 mg of saquinavir in combination with 200 mg of zidovudine. The primary treatment period was 16 weeks, with monthly extensions in patients who did not show major disease progression or toxicity. The main measures of the efficacy of therapy used were changes in CD4 cell counts and in the concentration of HIV-1 RNA in the plasma (as determined by quantitative polymerase chain reaction). The 600 mg dose of saquinavir in combination with zidovudine induced a 1.6 log (after 4 weeks) and a 0.7 log (after 16 weeks) median reduction in plasma RNA concentration; this reduction was greater than those seen in the other four treatment groups. The combination of 600 mg of saquinavir with zidovudine also resulted in a larger and more sustained improvement in the CD4 cell count than either saquinavir or zidovudine monotherapy or the other combination therapies. In the group receiving 200 mg of saquinavir in combination with zidovudine, the maximal median change in CD4 cell count occurred at week 2 (85 cells/mm3), and by week 16 had fallen to 15 cells/mm3. In the group receiving 600 mg of saquinavir plus zidovudine, the median change in CD4 cell count remained high for the 16-week period (median change of 48 cells/mm3 at week 2 and 61 cells/mm3 at week 16). Saquinavir was safe and very well tolerated, either alone or in combination with zidovudine. The incidence of adverse events was greater in the four groups receiving zidovudine therapy, and all the most commonly reported adverse events have previously been associated with zidovudine therapy. Few changes in laboratory values occurred during the study, except for known zidovudine-associated toxicities. The most frequent abnormalities were raised aspartate aminotransferase and alanine aminotransferase levels, depressed calcium levels, and abnormally high or low phosphate levels. Despite the low oral bioavailability of saquinavir, combined virological and immunological data show definite antiviral activity in vivo for the combination of saquinavir at 600 mg plus zidovudine at 200 mg (each three times daily). The combination of drugs with different mechanisms of action represents an advance in the treatment of HIV infection.

Adult↗

Safety and activity of saquinavir in HIV infection.

We evaluated saquinavir, an orally active, selective inhibitor of HIV proteinase, in a randomised, double-blind, dose-ranging study in 49 zidovudine-naive HIV-positive patients with few or no symptoms and CD4 cell counts of 500 or less. The study was designed to assess the antiviral activity and tolerability of saquinavir. Patients were randomised to receive 25, 75, 200, or 600 mg of saquinavir three times daily for 16 weeks. No serious adverse events occurred. CD4 cell counts showed a trend indicative of a dose response in favour of the 600 mg dosage, the maximum increase being seen around week 4. In none of the 8 patients with positive plasma viraemia at baseline did cultures become negative after treatment; peripheral blood mononuclear cell and plasma-viral load by culture and DNA and RNA PCR all showed a trend towards reduction at higher doses of saquinovir. Saquinavir was well tolerated in this group of previously untreated patients with few or no symptoms; this study shows that an HIV-proteinase inhibitor is active in HIV-infected patients.

CD4 Lymphocyte Count↗

Randomized trial in advanced ovarian cancer comparing cisplatin and carboplatin.

The aim of this multicenter randomized trial was to compare carboplatin (400 mg/m2) and cisplatin (100 mg/m2) in patients with untreated advanced epithelial ovarian cancer. Toxicity and treatment efficacy assessed by pathological response rate, progression-free survival, and survival were the endpoints of the study. One hundred seventy-three patients with advanced epithelial ovarian cancer, F.I.G.O. (International Federation of Gynecology and Obstetrics) stage III and IV were accrued in the trial. The median follow-up time was 15 months (maximum, 34); three patients in each treatment arm were not eligible (four, nonepithelial ovarian cancer type; one, no data, and one, stage II). Patient characteristics were similar in the two groups. In the carboplatin-treatment arm, the overall pathological response rate was 57.3% and the complete pathological response rate was 26.8%. In the cisplatin-treatment arm, the overall pathological response rate was 71.6% and the complete pathological response rate was 24.7%. There was no statistical difference in the two arms in survival or progression-free survival. Cisplatin was more nephrotoxic while carboplatin induced a higher degree of myelosuppression, especially thrombocytopenia; however, severe hematological toxicity was seldom observed. Carboplatin is a cisplatin analog with definite activity in ovarian cancer, but it is more active than the parent compound. Because of less nonhematological toxicity, carboplatin is undoubtedly a useful substitute in patients who cannot be given cisplatin. Further experience is needed to indicate whether or not carboplatin should completely displace cisplatin in the clinical treatment of ovarian cancer.

Adult↗

Clinical status of carboplatin.

Carboplatin, a cisplatin derivative, shows promise of being an effective weapon against ovarian, cervical, and small-cell lung cancer, as well as epidermoid cancer of the head and neck, with fewer toxic effects than cisplatin. It has successfully completed phase III investigation and clinical trials continue.

Animals↗

Treatment of acute leukaemia with m-AMSA in combination with cytosine arabinoside.

A series of 46 patients with acute leukaemia were treated with amsacrine (m-AMSA) and cytosine arabinoside (ara-C). Complete remission (CR) was achieved in 15 of 38 (40%) patients with acute myelogenous leukaemia (AML) and 4 of 8 (50%) patients with acute lymphoblastic leukaemia (ALL). The CR rate was significantly higher (P less than 0.05) for the younger, previously treated patients with AML (9/16) than for the older previously untreated ones (6/22), because of higher treatment mortality in the latter group. Myelosuppression was prolonged and profound. Major nonhaematological toxicity affected the gastrointestinal tract (nausea, vomiting, mucositis, bleeding and ileus associated with severe diarrhoea). Many patients also developed reversible hepatic dysfunction and two elderly patients died of cardiac arrhythmia. Further trials of this combination are justified in patients with relapsed or resistant leukaemia, but for older patients dose reduction is recommended.

Aged↗

New methodology for liposome targeting to specific cells.

The specificity of liposomes for different cell types was achieved by conjugation to monoclonal antibodies directed against various cell surface antigens. L929 mouse fibroblast cells were targeted with liposomes conjugated to anti-H2Kk. K562 cells, a human line derived from chronic myelogenous leukemia, were targeted with antiglycophorin. One murine T-lymphoma, AKR/J SL2, was targeted with anti-thy 1.1; another, R1.1, was targeted with anti-H2Kk. The following important parameters were established concerning efficacy of antibody-directed liposomes as a drug delivery system. (1) Targeted liposomes containing methotrexate-gamma-aspartate were 20-40 times more cytotoxic than the free drug or nonspecific liposomes. (2) The use of drugs such as methotrexate-gamma-aspartate, which are unable to enter cells without a carrier, eliminates the nonspecific effects of drug that may leak from the liposomes. (3) Liposomes conjugated to antibody have a higher valency than the soluble antibody and bind to cells with up to 1000-fold higher affinity constant. (4) Liposomes that interact with more than one type of ligand on the cell surface show marked resistance to inhibition of cell association by soluble ligands. (5) The optimal liposome size appears to vary from 0.05 to 0.1 mu, depending on target cell type.

Animals↗