Summary
Over a period of 14 years, 7,960 patients were treated in 228 phase I trials. In these patients, there were 75 complete and 432 partial responses for an overall objective response rate of 6%. Complete responses lasted a median of six months (range 1–18), while partial responses lasted a median of three months (range 1–17). Of note is that no drug has made it to the market which has not had a response in phase I trials. Responses were noted in very diverse histologic types of tumors. Although there were responses at doses which were as low as 3–5% of the recommended dose for phase II trials, the majority of responses did occur at 80–120% of the dose recommended for phase II trials. Although the response rate in phase I trials is indeed low, responses do occur. This response rate information should help the clinician provide facts for the patient considering a phase I trial with new anticancer agents. These findings also emphasize that although phase I trials are characteristically dose-finding studies, if no responses are noted in phase I studies, it is unlikely the drug will be used routinely in the clinic.
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Estey F, Hoth D, Leyland-Jones B, et al.: Therapeutic results in phase I studies. Proc Am Soc Clin Oncol 3:35, 1984
Staquet MJ, Byar DP, Green SB, Rozencweig M: Clinical predictivity of transplantable tumor systems in the selection of new drugs for solid tumors: Rationale for a three-stage strategy. Cancer Treat Rep 67:753–765, 1983
Vendetti JM: The National Cancer Institute Antitumor Drug Discovery Program, current and future perspectives: A commentary. Cancer Treat Rep 67:767–772, 1983
Salmon SE, Hamburger AW, Soehnlen B, Durie BGM, Alberts DS, Moon TE: Quantitation of differential sensitivity of human tumor stem cells to anti-cancer drugs. N Engl J Med 298:1321–1327, 1978
Alberts DS, Mackel C, Pocelinko R, Salmon SE: Phase I investigation of 9,10-anthracenedicarboxaldelydbis [4,5-dihydro-lH-imidazidfe-2-yl)hydrazone]dihydrochloride with correlative in vitro human tumor clonogenic assay. Cancer Res 42:1170–1175, 1982
Von Hoff DD, Coltman Jr CA, Forseth B: Activity of mitoxantrone in a human tumor cloning system. Cancer Res 41:1853–1855, 1981
Moertel CG, Hanley JA: The effect of measuring error on the results of therapeutic trials in advanced cancer. Cancer 38:388–394, 1976
Pazdur R, Samson M, Haas C, Schilches P, Baker L: Correlation of murine antitumor models in predicting clinical drug activity in non-small cell lung cancer: A six-year experience. Proc Am Soc Clin Oncol 3:219, 1984