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Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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PubMedDate not supplied

Ethical considerations related to the inclusion of women in clinical trials.

Clinical trials are the primary way the most promising new preventive, diagnostic, therapeutic, and palliative measures move from the basic science laboratory to the bedside. Attracting participants to clinical trials occurs at a painstakingly slow pace, delaying the public's access to new care modalities. Additional ways are needed to increase the public's awareness and understanding of the important role of clinical trials. As key members of the health and social welfare promotion team, nurse-midwives/midwives are well positioned to help advance the public's access to clinical trials information. Generic ethical issues related to human subjects review processes, their specific application to clinical trials, and the impact of recent HIPAA legislation are discussed.

Clinical Trials as Topic↗
PubMed2003

Clinical trials: where are we now?

Clinical trials in transplantation have focused on improving outcomes and minimizing side effects associated with renal transplantation. Although immunologic tolerance, which means complete freedom from immunosuppressive drugs and maintenance of excellent long-term graft function, has seldom been achieved, in rare cases, this has been accomplished. Most current clinical trials focus on minimization of steroid use and calcineurin inhibitor use as a step toward tolerance, sometimes termed prope tolerance. Alternatively, new immunosuppressive agents are studied to assess their efficacy in preventing graft rejection with the anticipation of lesser toxicity. This review is organized in a case presentation style with actual cases from the University of Wisconsin kidney transplant experience presented as illustrations of actual scenarios in clinical trials. Lessons learned from these particular patients are then summarized with reference to the literature associated with the case. Using this format, some of the important lessons learned from clinical trials are outlined and directions for future study are noted. Clinical trials have permitted a dramatic improvement in graft survival and lowering of infectious and malignant side effects over the past 30-40 years. Nevertheless, we remain far from achieving true tolerance in patients for a variety of reasons.

Calcineurin↗
PubMed1997

Evaluation of monoclonal antibodies to human immunodeficiency virus type 1 primary isolates by neutralization assays: performance criteria for selecting candidate antibodies for clinical trials. AIDS Clinical Trials Group Antibody Selection Working Group.

A collaborative study was organized to identify monoclonal antibodies (MAbs) that may be broadly and potently neutralizing for a panel of human immunodeficiency virus type 1 (HIV-1) low-passaged adult and pediatric primary isolates in peripheral blood mononuclear cells. Five laboratories evaluated a coded panel of seven human MAbs to HIV-1 subtype B envelope V3, CD4 binding region, gp41, and other conformationally sensitive determinants. Each laboratory measured neutralizing activity of the MAbs against the laboratory isolate HIV(MN) and a panel of 9 subtype B primary isolates. Antibodies were classified as suitable candidates for future clinical studies if they could neutralize at least half of the 9 primary isolates at a concentration of < or = 25 microg/mL for 90% viral inhibition. The study identified three MAbs that met stated performance criteria: IgG1b12, 2G12, and 2F5. These results may provide a rationale for examining the clinical efficacy, either singly or in combination, of the three MAbs.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Phases of a clinical trial.

Clinical trials are commonly conducted at hospitals, clinics, physicians' offices, universities, and in many other areas. This article describes the four phases of a clinical trial for a new medication, device, or treatment. This article will assist nurses caring for patients in clinical trials.

Clinical Trials as Topic↗
PubMed1991

A decade of progress in statistical methodology for clinical trials.

Clinical trials played a dominant and expanding role in the evaluation of new treatments during the decade of the 1980s. There were major improvements in the quality of clinical trials in many medical fields. There were also important developments in the methodology of designing, monitoring, conducting, analysing, reporting and interpreting clinical trials. This paper attempts to review some of these developments. A comprehensive review is beyond the abilities of any one individual. Consequently, this paper attempts to offer a broad stroke description of this area and to highlight specific topics of importance based on my particular experience. An extensive, but non-comprehensive bibliography is included to provide entry points to the literature of methodologic developments for clinical trials in the 1980s.

Clinical Trials as Topic↗
PubMed1999

Barriers to informed consent in clinical trials.

Clinical trials are a type of scientific study conducted in human beings. They are designed to evaluate the safety and effectiveness of new drugs, procedures, or other means of treating, diagnosing, or preventing diseases. The ethical issues involved in clinical trials are nothing new, but because of the increased access to studies, they are steadily affecting more people. The sheer volume of clinical trials, as well as the number of patients and professionals involved in them, has increased in the past decade. Informed consent is a key element of clinical research. Meaningful informed consent requires that subjects weight the associated risks and benefits of an experimental intervention and then voluntarily give consent. One concern regarding informed consent in research is the confusion between therapeutic intervention and experimental treatment. This confusion could lead to barriers in informed consent. This column addresses this concern and includes a case study to illustrate the misunderstandings that might arise from the patient who is compelled to consent to clinical trials because of his sense of hopelessness from a chronic health condition and the traditional medical intervention he is receiving.

Adult↗
PubMed2001

Equivalence testing with dental clinical trials.

Clinical trials whose purpose are to show equivalence of two or more treatments have traditionally utilized methods for demonstrating superiority, and, if no statistical differences are found, the treatments are assumed to be equivalent. Methods for directly demonstrating equivalence have been developed by the pharmaceutical industry to establish the bioequivalence between drug formulations. This approach should have significant future implications for dental research. It is presently well-characterized in the statistical literature, but is virtually unknown within the dental literature and has had limited documented application with dental clinical trials. The purpose of this paper is to consider equivalence testing with dental clinical trials. Equivalence and superiority testing are contrasted, and comparisons between parallel and crossover designs with equivalence testing are discussed. To exemplify equivalency trial methodology for dental research application, several examples are proposed, including, in detail, an implant overdenture clinical trial to test the equivalence of treatment outcome between a two- and a four-implant overdenture treatment. Sample size calculations for otherwise-identical crossover and parallel equivalence studies are demonstrated. Results show that for a power of 0.90, a sample size of 24 is required for the crossover trial and over 150 subjects for the parallel design. For this dental research application, the equivalence/crossover design methodology is shown to be an efficient and appropriate approach.

Cross-Over Studies↗
PubMed2005

Study designs and outcomes in antidepressant clinical trials.

Clinical trials of antidepressants are difficult to design and conduct. In fact, more than half of all recent clinical trials of commonly used antidepressants failed to show statistical superiority for the drug over placebo. This is not necessarily because of the ineffectiveness of the antidepressant, but rather because of an increased response to placebo. Factors that may contribute to these findings remain elusive. Using data from U.S. Food and Drug Administration (FDA) Summary Basis of Approval (SBA) reports and from studies conducted by our group, we reviewed methodological factors used in clinical trials of antidepressants. The 2 most notable factors affecting positive trials are (1) the inclusion of patients with more severe depression, and (2) the use of a flexible-dose design; these may yield results identifying true antidepressant-placebo differences. Severely ill patients with depression respond well to antidepressants but poorly to placebo. Flexible dosing paradoxically reduces the response to placebo without augmenting the response to the antidepressant. All of these findings suggest that the use of placebo is mandatory when assessing new antidepressants.

Antidepressive Agents↗
PubMed1993

[The Italian contribution to the application of high-technology methods to clinical trials].

Clinical trials are important research tools currently used in assessing new drugs and therapeutic strategies, which are unable to produce large effects evaluable in small series of patients. We describe methodological principles of clinical trials and significant advantages in their implementation produced by using a computer network for long-distance modem transmission of echocardiographic images and clinical data. This network has been recently developed in Italy and is operative at the University of Bari and the Associazione per la Ricerca in Cardiologia. Several clinical participating centers of the CEDIM Study and PHASE Study are connected in real time to a data center via modem by a special telephone network (RFD) of the Italian State Telephone Company (SIP). We describe the configuration, main features and applicative potential of such a powerful research tool in modem clinical trial methodology.

Cardiology↗
PubMed2004

A quantitative definition of severe psoriasis for use in clinical trials.

Clinical trials of new agents for severe psoriasis require clear, well-characterized and objective measurement criteria to define the study population. The purpose of this paper is to offer parameters defining 'severe' psoriasis for use in clinical trials. If patients have at least 10% body surface area (BSA) involved and a psoriasis area and severity index (PASI) score > or =12, they have severe disease. While this definition assures inclusion of only patients with severe disease, a disadvantage is that some patients with truly severe disease (as defined by the impact of their disease on their quality of life) will be excluded. It is necessary to accept this trade off in order to have objective criteria, consistent across centers involved in clinical trials, for identifying patients affected by severe psoriasis.

Body Surface Area↗
PubMed2002

Assessment of different treatment failure criteria in a cohort of relapsing-remitting multiple sclerosis patients treated with interferon beta: implications for clinical trials.

Clinical trials with interferons in relapsing-remitting multiple sclerosis have shown a modest effect on disability using fixed definitions of treatment failure to measure disease progression. However, in the course of the disease, treatment failure may be influenced by interrater variability and frequent remissions. Thus, the purpose of this study was to assess the clinical usefulness of different treatment failure criteria in a cohort of relapsing-remitting multiple sclerosis patients treated with interferon beta. We studied 252 patients with a follow-up of more than 2 years. We used four different criteria of treatment failure with increasing stringency (1 Expanded Disability Status Scale [EDSS] point increase confirmed at 3 months, 1 EDSS point increase confirmed at 6 months, 1.5 EDSS points increase confirmed at 3 months, and 1.5 EDSS points increase confirmed at 6 months). We divided treatment failure into permanent treatment failure and transient treatment failure. We considered permanent treatment failure when treatment failure was confirmed on the last two scheduled visits and transient treatment failure when treatment failure was not confirmed on these visits at different time points (9, 12, 18, and 24 months). We calculated the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the different criteria of treatment failure to identify patients who achieved a high degree of disability after 4 years of follow-up. Regardless of the stringency of treatment failure definitions, a variable proportion of patients with treatment failure had transient treatment failure depending on the criterion applied. Patients with transient treatment failure had a significantly lower EDSS at entry compared with those with permanent treatment failure or no treatment failure. The number of relapses in patients with transient treatment failure did not differ from that of patients with permanent treatment failure. The criterion of confirmed 1 EDSS point increase at 6 months showed the best sensitivity (76.5%), with satisfactory specificity (89%). Our study shows that a large proportion of patients treated with interferon experience transient treatment failure that may affect outcome interpretation in clinical trials. Using a more strict criterion, as extending time to confirmation of EDSS deterioration, and longer follow-up may reduce this proportion of patients with transient treatment failure and improve the validity of the results attained in clinical trials.

Adjuvants, Immunologic↗
PubMed1987

Should the elderly hypertensive be treated? Evidence from clinical trials.

Clinical trials for over 15 years have addressed the therapeutic utility of treating elderly hypertensives. Many early trials showed no treatment effects. Because of the recent publication of new information, a review of available evidence concerning this issue was undertaken. Eight randomized clinical trials were assessed regarding trial design. The studies varied according to generalizability, diagnostic criteria, choice of therapy, outcome measures assessed, evaluation of compliance, methods of analysis, duration of follow-up, determination of side effects, and ability to exclude a type 2 error. While many of the earlier studies found no treatment effects, they lacked methodologic rigor; more recent studies demonstrated positive treatment effects. Pooling of results from similar trials supports a notable treatment effect in the prevention of stroke. There is also evidence that the elderly are not more susceptible to side effects of antihypertensive drugs, as is generally believed. The best evidence suggests the hypertensive elderly should be treated.

Aged↗
PubMed2001

Integration of trastuzumab into adjuvant systemic therapy of breast cancer: ongoing and planned clinical trials.

Clinical trials using the humanized version of the anti-HER2 murine monoclonal antibody 4D5, trastuzumab, have shown antitumor activity in patients with HER2-positive metastatic breast cancer. Improved response and survival rates have been shown when trastuzumab was added to first-line combination chemotherapy with anthracycline/cyclophosphamide or paclitaxel compared with the same chemotherapy alone. Because of the promising safety and efficacy profile of trastuzumab in the metastatic setting, this novel biologic has now entered adjuvant breast cancer trials in both the United States and Europe. Five clinical trials are discussed in this report, capturing the evolving role of trastuzumab as adjuvant therapy for breast cancer.

Antibodies, Monoclonal↗