Avtor/Urednik		O'Quigley, J; Hughes, MD; Fenton, T
Naslov		Dose-finding designs for HIV studies
Tip		članek
Vir		Biometrics
Vol. in št.		Letnik 57, št. 4
Leto izdaje		2001
Obseg		str. 1018-29
Jezik		eng
Abstrakt		We present a class of simple designs that can be used in early dose-finding studies in HIV. Such designs, in contrast with Phase I designs in cancer, have a lot of the Phase II flavor about them. Information on efficacy is obtained during the trial and is as important as that relating to toxicity. The designs proposed here sequentially incorporate the information obtained on viral reduction. Initial doses are given from some fixed range of dose regimens. The doses are ordered in terms of their toxic potential. At any dose, a patient can have one of three outcomes: inability to take the treatment (toxicity), ability to take the treatment but insufficient reduction in viral load (viral failure), and ability to take the treatment as well as a sufficient reduction of viral load (success). A clear goal for some class of designs would be the identification of the dose leading to the greatest percentage of successes. Under certain assumptions, which we identify and discuss, we can obtain efficient designs for this task. Under weaker, sometimes more realistic assumptions, we can still obtain designs that have good operating characteristics in identifying a level, if such a level exists, having some given or greater success rate. In the absence of such a level, the designs will come to an early closure, indicating the ineffectiveness of the new treatment.
Deskriptorji		ANTI-HIV AGENTS HIV INFECTIONS CHILD CLINICAL TRIALS, PHASE I CLINICAL TRIALS, PHASE II MODELS, STATISTICAL