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Despite both the increase in basic biologic knowledge and the fact that many new agents have reached various stages of development during the last 10 years, the number of new treatments that have been approved for patients has not increased as expected. We propose the multi-arm, multi-stage trial design as a way to evaluate treatments faster and more efficiently than current standard trial designs. By using intermediate outcomes and testing a number of new agents (and combinations) simultaneously, the new design requires fewer patients. Three trials using this methodology are presented.

Background: Clusterin is a cytoprotective chaperone protein that promotes cell survival and confers broad-spectrum treatment resistance. OGX-011 is a 2'-methoxyethyl modified phosphorothioate antisense oligonucleotide that is complementary to clusterin mRNA and has been reported to inhibit clusterin expression and enhance drug efficacy in xenograft models. The primary objective of this clinical study was to determine a biologically effective dose of OGX-011 that would inhibit clusterin expression in human cancer. Methods: Subjects (n = 25) with localized prostate cancer with high-risk features who were candidates for prostatectomy were treated with OGX-011 by 2-hour intravenous infusion on days 1, 3, and 5 and then weekly from days 8-29 combined with androgen blockade starting on day 1; prostatectomy was performed on days 30-36. Six different doses were tested, from 40 to 640 mg. OGX-011 plasma and prostate tissue concentrations were measured by an enzyme-linked immunosorbent assay method, and the pharmacokinetics of OGX-011 were determined from these data. Prostate cancer tissue, lymph nodes, and serial samples of peripheral blood mononuclear cells were assessed for clusterin expression using quantitative real-time polymerase chain reaction and immunohistochemistry. All statistical tests were two-sided. Results: Only grade 1 and 2 toxicities were observed. The plasma half-life of OGX-011 was approximately 2-3 hours, and the area under the concentration versus time curve and [C.sub.MAX] (peak plasma concentration) increased proportionally with dose ([P.sub.trend]

Background: New targeted, non-cytotoxic anticancer agents, such as small-molecule kinase inhibitors, pose challenges to the current phase I paradigm of dose selection based on toxicity. Moreover, increasing the drug dose to toxicity may be unnecessary for drug effect, making the use of maximum tolerated dose as a surrogate of effective dose inappropriate in the phase I setting. Because little is known about the optimal methods of recommended phase II dose selection of targeted, non-cytotoxic therapies, we reviewed the strategies that were used in completed phase I studies of these drugs. Methods: We retrieved 60 publications of phase I studies involving 31 single agents representative of the most common targets of interest in the oncology literature. For each publication, we abstracted data regarding patient population, starting dose, methods of dose escalation and determination of recommended phase II dose, and inclusion of correlative studies in study conduct. Results: Of the 60 completed phase I studies, 36 used toxicity and eight used pharmacokinetic data as endpoints for selection of the recommended phase II dose. Nontraditional endpoints, such as measures of molecular drug effects in tumor or surrogate tissue or functional imaging studies, were not routinely incorporated into the study design and rarely formed the primary basis for dose selection. Conclusions: To date, phase I studies of targeted anticancer agents have generally used traditional endpoints for selection of the recommended phase II dose. More research is needed to define suitable molecular measures of drug effect and the means to incorporate them in the early drug development process. [J Natl Cancer Inst 2004;96:990-7]

Anticancer cytotoxic agents go through a process by which their antitumor activity--on the basis of the amount of tumor shrinkage they could generate--has been investigated. In the late 1970s, the International Union Against Cancer and the World Health Organization introduced specific criteria for the codification of tumor response evaluation. In 1994, several organizations involved in clinical research combined forces to tackle the review of these criteria on the basis of the experience and knowledge acquired since then. After several years of intensive discussions, a new set of guidelines is ready that will supersede the former criteria. In parallel to this initiative, one of the participating groups developed a model by which response rates could be derived from unidimensional measurement of tumor lesions instead of the usual bidimensional approach. This new concept has been largely validated by the Response Evaluation Criteria in Solid Tumors Group and integrated into the present guidelines. This special article also provides some philosophic background to clarify the various purposes of response evaluation. It proposes a model by which a combined assessment of all existing lesions, characterized by target lesions (to be measured) and nontarget lesions, is used to extrapolate an overall response to treatment. Methods of assessing tumor lesions are better codified, briefly within the guidelines and in more detail in Appendix I. All other aspects of response evaluation have been discussed, reviewed, and amended whenever appropriate. [J Natl Cancer Inst 2000; 92:205-16]

Background: Tumor shrinkage is a common end point used in screening new cytotoxic agents. The standard World Health Organization criterion for partial response is a 50% or more decrease in the sum of the products of two measurements (the maximum diameter of a tumor and the largest diameter perpendicular to this maximum diameter) of individual tumors. However, theoretically, the simple sum of the maximum diameters of individual tumors is more linearly related to cell kill than is the sum of the bidimensional products. It has been hypothesized that the calculation of bidimensional products is unnecessary, and a 30% decrease in the sum of maximum diameters of individual tumors (assuming spherical shape and equivalence to a 50% reduction in the sum of the bidimensional products) was proposed as a new criterion. We have applied the standard response and the new response criteria to the same data to determine whether the same number of responses in the same patients would result. Methods: Data from 569 patients included in eight studies of a variety of cancers were reanalyzed. The two response criteria were separately applied, and the results were compared using the K statistic. The importance of confirmatory measurements and the frequency of nonspherical tumors were also examined. In addition, for a subset of 128 patients, a unidimensional criterion for disease progression (30% increase in the sum of maximum diameters) was applied and compared with the standard definition of a 25% increase in the sum of the bidimensional products. Results: Agreement between the unidimensional and bidimensional criteria was generally found to be good. The K statistic for concordance for overall response was 0.95. Conclusion: We conclude that one dimensional measurement of tumor maximum diameter may be sufficient to assess change in solid tumors. [J Natl Cancer Inst 1999; 91:523-8]