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Measuring Placebo Effect by Elimination and Investigating Mechanism of Action
This study is currently recruiting participants.
Verified by King Faisal Specialist Hospital & Research Center, September 2007
Sponsors and Collaborators: King Faisal Specialist Hospital & Research Center
King Abdulaziz City for Science & Technology (KACST)
Information provided by: King Faisal Specialist Hospital & Research Center
ClinicalTrials.gov Identifier: NCT00426010
  Purpose

We propose to measure the effect of placebo by elimination as well as by a "balanced placebo" design, determine its interaction with active drug, and explore whether placebo exerts part of its effect at the pharmacokinetics level.


Condition Intervention
Placebo Effect
Placebo Mechanisms of Action
Drug: caffeine/placebo

MedlinePlus related topics: Caffeine
Drug Information available for: 3,7-Dihydro-1,3,7-trimethyl-1H-purine-2,6-dione Caffeine citrate
U.S. FDA Resources
Study Type: Interventional
Study Design: Treatment, Randomized, Double-Blind, Placebo Control, Crossover Assignment, Pharmacokinetics/Dynamics Study
Official Title: Measuring Placebo Effect by Elimination and Investigating Its Mechanism of Action

Further study details as provided by King Faisal Specialist Hospital & Research Center:

Primary Outcome Measures:
  • 4 hours area under the curve (AUC) of peripheral systolic blood pressure
  • 4 hours area under the curve (AUC) of energy level measured by Visual Analogue Scales.
  • 4 hours area under the curve (AUC) of alertness level measured by Visual Analogue Scales.
  • 4 hours area under the curve (AUC) of nausea measured by Visual Analogue Scales.

Secondary Outcome Measures:
  • Cmax of serum caffeine (in a subgroup)
  • Tmax of serum caffeine (in a subgroup)
  • t1/2 of serum caffeine (in a subgroup)
  • AUC of serum caffeine (in a subgroup)

Estimated Enrollment: 180
Study Start Date: January 2007
Detailed Description:

Placebos have been in use for centuries in medical practice. However, there is continued controversy regarding their effectiveness and mechanisms of action.

The results of the study are expected to further our understanding of a widely used medical intervention, i.e., placebo, and of how to maximize its potential beneficial effect. It will also help assess the appropriateness of measuring the placebo effect by elimination, which has important ethical implications in relation to the design of randomized clinical trials.

Comparison: caffeine vs placebo. Dependent variables:4 hours area under the curve (AUC) of pharmacodynamics endpoints as well as pharmacokinetics endpoints in a subgroup.

  Eligibility

Ages Eligible for Study:   18 Years to 40 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Males and nonpregnant females 18 and 40 years of age with at least high school education.

Exclusion criteria:

  • Include evidence of clinically relevant deviation from normal health (such that it may affect the endpoints, make the ingestion of caffeine dangerous, or affect the pharmacokinetics/pharmacodynamics of caffeine),
  • Pregnancy,
  • Poor venous access,
  • Hypertension (more than 140/90),
  • Heart disease,
  • History of panic attacks,
  • Average daily caffeine consumption of more than 300 or less than 100 mg,
  • Smoking,
  • Alcohol abuse,
  • Taking any medication other than birth control bills (including over-the-counter drugs) within one week from starting the study,
  • Hypersensitivity to caffeine or related compounds,
  • Hemoglobin of less than 13 gm/L, and recent (one week) acute illness
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00426010

Contacts
Contact: Muhammad M Hammami, MD, PhD 966 1 4424527 muhammad@kfshrc.edu.sa

Locations
Saudi Arabia
Center for Clinical Studies & Empirical Ethics, KFSH & RC Recruiting
Riyadh, Saudi Arabia, 11211
Principal Investigator: Muhammad M Hammami, MD, PhD            
Sponsors and Collaborators
King Faisal Specialist Hospital & Research Center
King Abdulaziz City for Science & Technology (KACST)
Investigators
Principal Investigator: Muhammad M Hammami, MD, PhD KFSH & RC, Riyadh
  More Information

Study ID Numbers: RAC# 2051072, KACST:ARP-26-45
Study First Received: January 23, 2007
Last Updated: September 17, 2007
ClinicalTrials.gov Identifier: NCT00426010  
Health Authority: Saudi Arabia: Research Advisory Council, KFSH & RC;   Saudi Arabia: King Abdulaziz City for Science & Technology (KACST)

Keywords provided by King Faisal Specialist Hospital & Research Center:
Placebo effect
Caffeine
Systolic BP
VAS

Study placed in the following topic categories:
Caffeine citrate
Caffeine

Additional relevant MeSH terms:
Phosphodiesterase Inhibitors
Molecular Mechanisms of Pharmacological Action
Therapeutic Uses
Physiological Effects of Drugs
Central Nervous System Stimulants
Enzyme Inhibitors
Central Nervous System Agents
Pharmacologic Actions

ClinicalTrials.gov processed this record on January 13, 2009