Why aren't participants randomized to doses in Phase I clinical trials?
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| Conversely, new approaches are needed to guide development of drug combinations since both standard phase II approaches and phase II-III randomized trials have a high risk of misleading. SummaryTraditional randomized clinical trials approaches are often inefficient, wasteful, and unreliable. | |
33 Citations | It is suggested that although the usual methods for choosing starting doses and dose-escalation schemes for phase I studies are safe, they are overly conservative and delay opportunities for therapeutic benefit in phase I and subsequent phase II trials. |
| Acute care randomized clinical trials are more vulnerable to premature discontinuation than nonacute care randomized clinical trials and have an approximately four-fold higher risk of discontinuation due to slow recruitment. | |
126 Citations | Participants in phase I clinical trial have high expectations regarding the success of experimental therapy and discount potential toxicity. |
16 Citations | This may help improving the ability of phase I trials of targeted agents to predict doses that will eventually be registered—as this ability has been reported to be poorer for targeted agents than for phase I trials evaluating conventional cytotoxic chemotherapies [8]. |
10 Citations | However, the lack of reproducibility is more likely due to small sample sizes for phase I trials and differences between patients enrolled on phase I trials and those enrolled on phase II and II trials. |
Open access 01 Jul 1993 11 Citations | Randomized clinical trials would gain from incorporating a concern for timing as well as dosing in all three stages of clinical trials (Phase I, II and III focusing on toxicity, efficacy and a comparison with the current best treatment, respectively) and could be cost-effectively preceded by 'Phase 0' trials so as to detect, sooner and with smaller sample sizes, desired or undesired effects that may otherwise be missed. |
35 Citations | This may be feasible when trial participants are in a controlled environment such as in early phase clinical trials, however it becomes problematic in trials where patients are in an out-patient clinic setting such as in late phase drug development. |
8 Citations | Randomized phase II clinical trials can be an efficient means of evaluating several potential new treatments prior to a comparative phase III clinical trial. |
55 Citations | Randomized phase II/III trials use an adaptive trial design that combines these two types of trials in one, with potential gains in time and reduced numbers of patients required to be treated. |
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