Interim DSMB Named for National Lung Screening Trial
An interim Data and Safety Monitoring Board (DSMB) has been appointed for the 50,000-participant National Lung Screening Trial (NLST), following the resignation of the trial's original DSMB on March 26. The DSMB Chair, Dr. Sylvan Green, Arizona Cancer Center, explained that the board was resigning because individual members do not have liability insurance coverage as part of the professional services contract under which they were secured for the trial.
In response, officials from NCI (which is sponsoring the trial) and the National Institutes of Health (NIH) are working together to resolve this issue and quickly appointed an interim DSMB. The interim board is composed of NIH scientists with appropriate clinical and research expertise.
NCI policies require that all clinical trials that the institute sponsors have a DSMB. The activities of DSMBs are distinct from those performed by IRBs, which review and approve research protocols for clinical trials prior to their launch. Both IRBs and DSMBs, however, play critical roles in ensuring patient safety.
A DSMB is intimately familiar with a trial's protocol and its plans for monitoring patient safety and data collection. The board's central function is to review interim analyses of outcome data and cumulative toxicity data summaries. Based on these reviews, the board determines whether the trial should continue as originally designed, be amended, or possibly even be terminated. The board may also recommend other actions based on these reviews.
For example, as recently reported (NCI Cancer Bulletin, March 16), the DSMB of a phase III clinical trial comparing five years of adjuvant chemotherapy for breast cancer using either tamoxifen alone or switching after several years to the aromatase inhibitor exemestane recommended that results data be released before the trial was complete because of the significant benefit seen in overall survival in patients treated with exemestane. The need for liability indemnification for such consultation and advice is a question that is now being addressed.
Launched in 2002, NLST is the largest trial of CT screening for lung cancer. A randomized, controlled trial, NLST is comparing spiral computed tomography and standard chest X-ray for the early detection of lung cancer. Nearly 50,000 current or former smokers have enrolled in NLST at more than 30 study sites across the country. As of February 2004, the trial reached full enrollment in record time and is closed to further enrollment. Nothing affecting patients, patient safety, or data collection has changed; the focus of the trial and its outcome have not been altered.
Further details on this development will be reported as they become available. For more information on NCI and NIH policies on data and safety monitoring of clinical trials, visit http://deainfo.nci.nih.gov/grantspolicies/datasafety.htm (NCI) and http://grants.nih.gov/grants/guide/notice-files/not98-084.html (NIH).