The Department of Biostatistics at the University of Texas MD Anderson Cancer Center works on developing innovative designs for clinical trials and biological experiments, analysis of complex data, and consulting and collaborating with clinical and biological investigators. Thousands of clinical trials are conducted at MD Anderson Cancer Center each year. Most of them are phase I/II trials, and a small number are phase III trials organized by biopharmaceutical companies. A large fraction of these phase I/II trials are initiated by MD Anderson investigators. Faculty members in the Department of Biostatistics are responsible for the statistical designs of these trials.
Although many statistical designs have been developed for phase I/II trials, most were not developed specifically for oncology clinical trials. Oncology trials usually have a small sample size due to the heterogeneity of patients, the large number of competing trials, and the fact that each particular subtype of cancer is a rare disease. Oncology trials need to consider multiple end points, such as tumor response, patient survival, and toxicity. To accommodate the special needs of oncology trials, the biostatisticians develop innovative adaptive designs to maximize the benefits of both patients participating in the trial and future patients, to make the most efficient use of patients as a valuable resource for competing trials, and to accelerate the drug development, discovery, and testing processes.
STATISTICAL RESEARCH ON CLINICAL TRIAL DESIGN
Faculty in the Department of Biostatistics advocate adaptive clinical trial designs (1,2,3,4,5,6,7) and other innovative early-phase designs (8,9,10,11,12,13,14,15). Some examples of adaptive designs are discussed next. We developed a statistical design for phase II clinical trials that better selects drug candidates for phase III trials (11). Currently, most phase II oncology trials use complete remission (CR) of the cancer as the primary end point. Drugs associated with higher CR rates are evaluated in subsequent phase III trials, which are usually required to demonstrate that the drug increases the patient’s survival time. Although achieving CR is necessary to prolong survival, it is not a sufficient measurement because patients may experience cancer relapse shortly after achieving CR. This discrepancy is one of the major reasons for the high failure rates (60%) of phase III trials (15). Thus, it is desirable to evaluate survival outcomes in phase II trials. Based on these considerations, our phase II design uses information on both CR and survival. There are several innovative features of this design. It makes full use of the information that accumulates in all stages of the trial and thus saves valuable patient resources. Interim stopping rules for toxicity, futility, and efficacy are defined. To evaluate the efficacy of treatments, patients are assigned to therapy in a randomized adaptive fashion. This means that patients in ...