Data monitoring committees: Promoting best practices to address emerging challenges.

BACKGROUND AND PURPOSE: Data monitoring committees are responsible for safeguarding the interests of study participants and assuring the integrity and credibility of clinical trials. The independence of data monitoring committees from sponsors and investigators is essential in achieving this mission. Creative approaches are needed to address ongoing and emerging challenges that potentially threaten data monitoring committees' independence and effectiveness. METHODS: An expert panel of representatives from academia, industry and government sponsors, and regulatory agencies discussed these challenges and proposed best practices and operating principles for effective functioning of contemporary data monitoring committees. RESULTS AND CONCLUSIONS: Prospective data monitoring committee members need better training. Options could include didactic instruction as well as apprenticeships to provide real-world experience. Data monitoring committee members should be protected against legal liability arising from their service. While avoiding breaches in confidentiality of interim data remains a high priority, data monitoring committees should have access to unblinded efficacy and safety data throughout the trial to enable informed judgments about risks and benefits. Because overly rigid procedures can compromise their independence, data monitoring committees should have the flexibility necessary to best fulfill their responsibilities. Data monitoring committee charters should articulate principles that guide the data monitoring committee process rather than list a rigid set of requirements. Data monitoring committees should develop their recommendations by consensus rather than through voting processes. The format for the meetings of the data monitoring committee should maintain the committee's independence and clearly establish the leadership of the data monitoring committee chair. The independent statistical group at the Statistical Data Analysis Center should have sufficient depth of knowledge about the study at hand and experience with trials in general to ensure that the data monitoring committee has access to timely, reliable, and readily interpretable insights about emerging evidence in the clinical trial. Contracts engaging data monitoring committee members for industry-sponsored trials should have language customized to the unique responsibilities of data monitoring committee members rather than use language appropriate to consultants for product development. Regulatory scientists would benefit from experiencing data monitoring committee service that does not conflict with their regulatory responsibilities.

Understanding the functions and operations of data monitoring committees: Survey and focus group findings.

BACKGROUND: The use of data monitoring committees in the conduct of clinical trials has increased and evolved, but there is a lack of published information on when data monitoring committees are needed and utilized, the acceptable range of data monitoring committee practices, and appropriate qualifications of data monitoring committee members. METHODS: To gain a better understanding of data monitoring committee operations and areas for improvement, the Clinical Trials Transformation Initiative conducted a survey and set of focus groups. A total of 143 respondents completed the online survey: 76 data monitoring committee members, 52 sponsors involved with organization of data monitoring committees, and 15 statistical data analysis center representatives. There were 42 focus group participants, including data monitoring committee members; patients and/or patient advocate data monitoring committee members; institutional review board and US Food and Drug Administration representatives; industry, government, and non-profit sponsors; and statistical data analysis center representatives. RESULTS: Participants indicated that the primary responsibility of a data monitoring committee is to be an independent advisory body representing the interests of trial participants by assessing the risk and benefit ratio in ongoing trials. They noted that data monitoring committees must have access to unmasked data in order to perform this role. No clear consensus emerged regarding specific criteria for requiring a data monitoring committee for a given trial, and some participants felt data monitoring committees may be overused. Respondents offered suggestions for the data monitoring committee charter and communications with sponsors, institutional review boards, and regulators. Overall, data monitoring committee members reported that they are able to function independently and their recommendations are almost always accepted by the sponsor. Participants indicated that there are no standards or guidelines pertaining to qualifications of data monitoring committee members. Furthermore, only 8% (6/72) of data monitoring committee member survey respondents received any formal training, and 94% (68/72) were not aware of any training programs. CONCLUSION: Findings from the survey and focus groups provide a better understanding of contemporary data monitoring committee operations and insights regarding challenges and best practices. Overall, it was clear that increased training will be needed to prepare the next generation of qualified data monitoring committee members to meet the growing demand. These findings can be used by Clinical Trials Transformation Initiative and others to develop recommendations and tools to improve data monitoring committee operations and the overall quality of trial oversight.

Effects of sources of variability on sample sizes required for RCTs, applied to trials of lipid-altering therapies on carotid artery intima-media thickness.

OBJECTIVE: Studies measuring progression of carotid artery intima-media thickness (cIMT) have been used to estimate the effect of lipid-modifying therapies cardiovascular event risk. The likelihood that future cIMT clinical trials will detect a true treatment effect is estimated by leveraging results from prior studies. The present analyses assess the impact of between- and within-study variability based on currently published data from prior clinical studies on the likelihood that ongoing or future cIMT trials will detect the true treatment effect of lipid-modifying therapies. METHODS: Published data from six contemporary cIMT studies (ASAP, ARBITER 2, RADIANCE 1, RADIANCE 2, ENHANCE, and METEOR) including data from a total of 3563 patients were examined. Bayesian and frequentist methods were used to assess the impact of between study variability on the likelihood of detecting true treatment effects on 1-year cIMT progression/regression and to provide a sample size estimate that would specifically compensate for the effect of between-study variability. RESULTS: In addition to the well-described within-study variability, there is considerable between-study variability associated with the measurement of annualized change in cIMT. Accounting for the additional between-study variability decreases the power for existing study designs. In order to account for the added between-study variability, it is likely that future cIMT studies would require a large increase in sample size in order to provide substantial probability (> or =90%) to have 90% power of detecting a true treatment effect.Limitation Analyses are based on study level data. Future meta-analyses incorporating patient-level data would be useful for confirmation. CONCLUSION: Due to substantial within- and between-study variability in the measure of 1-year change of cIMT, as well as uncertainty about progression rates in contemporary populations, future study designs evaluating the effect of new lipid-modifying therapies on atherosclerotic disease progression are likely to be challenged by large sample sizes in order to demonstrate a true treatment effect.

Study design of the Medical Therapy of Prostatic Symptoms (MTOPS) trial.

Alpha-blockers and 5-alpha-reductase inhibitors are medical therapies that are being used as alternatives to surgical interventions to relieve symptoms of benign prostatic hyperplasia (BPH). Taken as monotherapy, alpha-blockers and 5-alpha-reductase inhibitors have each been shown to provide relief from BPH symptoms. Treatment with finasteride over 4 years has been shown to reduce both BPH symptoms and the likelihood of acute urinary retention and the need for surgery. Direct comparison of the alpha-blocker terazosin with finasteride has been done, but only for a period of 1 year. The Medical Therapy of Prostatic Symptoms (MTOPS) trial is a multicenter, randomized, placebo-controlled, double-masked clinical trial designed to evaluate the long-term efficacy of the alpha-blocker doxazosin and the 5-alpha-reductase inhibitor finasteride, whether taken as a monotherapy or in combination, in preventing or delaying the progression of BPH. We describe in this paper the design of the MTOPS trial, the concept of BPH progression, the definition and methods of determining the primary outcome events and the proposed statistical analysis methods. A unique feature of MTOPS is the inclusion of prostate biopsies on a subgroup of randomized participants. Volunteers among randomized participants are to undergo a biopsy of the prostate at predetermined time points during the trial. Studies that will be conducted using the tissue specimens collected in MTOPS can potentially provide information at the molecular level on the natural history of BPH among medically treated and untreated men with moderate to severe symptoms of BPH.