The Multi-Institutional Phase I Study: Disadvantages Without Advantages?

Abstract

The famous Dutch soccer player Johan Cruijf, who now is a commentator for Dutch television, introduced the saying that “Every advantage has its disadvantage” (or vice versa). Does this also apply to the multi-institutional phase I study? Phase I studies are the core of drug development. Among many other aims, they are essential for the identification of safety risks and for the selection of a drug dose that can be used for further development. Drug development is a highly competitive field, and therefore, time is of the essence. This means that every phase I study should provide information as quickly as possible; with the highest possible certainty; and, preferably, with the fewest possible patients, given the limited chance for actual patient benefit. With the assumption that adding more centers would be the optimal strategy to speed patient accrual, pharmaceutical industries in particular are currently pursuing the model of large, multicenter, phase I studies in a continuous drive to further expand these numbers. In addition to this, end points also are changing—from the usual and well-defined maximum-tolerated dose (MTD) to the more obscure and undefined optimal biologic dose (OBD)— because of the shifting focus of mechanism of action of anticancer drugs. In the current issue of theJournalofClinicalOncology, Dowlati et al 1 present an interesting literature review that involves 463 phase I studies that were published during 8 years in two major oncology journals: JCO and Clinical Cancer Research. This selection presents a possible limitation of the analysis, because both journals, although international, are based in the United States. The analysis, therefore, seems to present some publication imbalance, as 70% of the reviewed studies were performed in North America. Although this may cause the performance of phase I studies performed in the rest of the world to be overlooked, it is likely a minor issue when assessing the results of the study. Nearly 60% of the reported studies were pharmaceutical industry–sponsored, which reflects new drug development that largely is—and will likely remain—a pharmaceutical industry–related initiative. Interestingly, only 30% of the studies reported the accrual time. If we first look at the number of sites involved, 55% of phase I studies were performed at a single institution, whereas other studies were performed in two to 16 sites. The large numbers at the upper boundary are surprising, because it is a real challenge to keep all sites informed on a real-time basis about safety issues observed in patients. Although the authors indicated that there was no significant change over time in the proportion of studies that involved multiple institutions, it is notable that 17.3% of the 249 trials reported until 2003 involved three or more sites, whereas 27% of the 214 trials reported in 2003 and beyond involved three or more sites. This is consistent with the collective experience and the concerns of numerous investigators in phase I trials, and it probably indicates that we indeed are involving more and more centers in phase I trials. There was no correlation between the number of participating sites and the mechanism of drug action. One would have expected that, in studies with potentially difficult accrual because of limitations (such as the presence of a specific and infrequently expressed molecular target), more centers would have been required. Apparently, the trend is not to limit the involvement of larger numbers of centers to only such studies but rather to pursue the expansion of the number of participating centers in all phase I studies. In the analysis of Dowlati et al, 1 chemoradiotherapy and gene therapy phase I studies often involved three or more sites. Diseasespecific phase I studies also were more likely to be multi-institutional compared with general solid tumor studies. In contrast, there did not seem to be an association between the involved sponsor and the number of participating institutions. The possibility of bias in this observation may be related to the fact that the analysis basically involved only industry-initiated and NCI-related studies. Other independent organizations, such as the European Organisation for Research and Treatment of Cancer, have always minimized the numbers of sites in phase I studies but were not part of the analysis. Accrual time was not different when comparing trials that in