Clinical Trial Experimental Arm

AKA: Clinical Trial Treatment Arm.
Example(s):
- In a Single-Arm Clinical Trial, there is only an experimental arm (i.e. there is only a clinical trial arm which is the one receiving the experimental treatment).
- In a Two-Arm Clinical Trial, there is an experimental arm (clinical trial arm receiving the experimental treatment) while the other clinical arm is a control arm (a placebo comparator arm or an active (non-experimental treatment) comparator arm.
- In a Three-Arm Clinical Trial, there can be an experimental arm (clinical trial arm receiving the experimental treatment) and control arms (a placebo comparator arm and an active (non-experimental treatment) comparator arm.
- In a Multi-Arm Clinical Trial such as NCT01910259:MS-SMART there can be 3 experimental arms (the fluoxetine, riluzole, and amiloride arms) and a placebo comparator arm.
- …
Counter-Example(s):
- a Control Arm,
- an Active Comparator Arm,
- a Placebo Comparator Arm,
- a Sham Comparator Arm,
- a No-Intervention Arm.
See: Single-Arm Clinical Trial, Multi-Arm Clinical Trial, Placebo-Controlled Clinical Trial, Exploratory Clinical Trial, Confirmatory Clinical Trial, Parallel Clinical Trial, Crossover Clinical Trial.

References

↑ Pushpakom SP, Taylor C, Kolamunnage-Dona R, Spowart C, Vora J, García-Fiñana M, et al. Telmisartan and insulin resistance in HIV (TAILoR): protocol for a dose-ranging phase II randomised open-labelled trial of telmisartan as a strategy for the reduction of insulin resistance in HIV-positive individuals on combination antiretroviral therapy. BMJ Open. 2015; 5:e009566.
↑ Magirr D, Jaki T, Whitehead J. A generalized Dunnett test for multi-arm multi-stage clinical studies with treatment selection. Biometrika. 2012; 99:494–501.

(Cohen et al., 2015) ⇒ Dena R. Cohen, Susan Todd, Walter M. Gregory, and Julia M. Brown (2015). "Adding a treatment arm to an ongoing clinical trial: a review of methodology and practice.". In: Trials, 16(179).
- QUOTE: This review investigates the addition of a new treatment arm to an ongoing trial within the following scope: the trial has already begun recruitment and the randomisation is still open when the new treatment is added, the trial has a confirmatory primary objective, the trial is designed using frequentist methodology (due to the differences in assumptions and considerations with Bayesian methodology), and the entire treatment arm is new rather than an amendment to an existing arm.

(Evans, 2010) ⇒ Scott R. Evans (2010). "Clinical trial structures". In: Journal of experimental stroke & translational medicine, 3(1), 8.
- QUOTE: The simplest trial design is a single-arm trial. In this design, a sample of individuals with the targeted medical condition is given the experimental therapy and then followed over time to observe their response. This design is employed when the objective of the trial is to obtain preliminary evidence of the efficacy of the treatment and to collect additional safety data, but is not generally used as confirmation of efficacy. The design may be desirable when the available patient pool is limited and thus it is not optimal to randomize many participants to a control arm.