Phases of Clinical Research


  • Phases of clinical research are the steps taken to gather evidence to determine whether a novel intervention or treatment is safe and effective for clinical use
  • primarily refers to the process of clinical drug development, which begins with the process of drug design and discovery, but is applied more widely to other medical interventions
  • for drugs, the entire process may take 10-20 years and cost over $1 billion
  • published studies may not adhere strictly to the phase designations


  • in vitro and in vivo animal studies
  • assess efficacy, toxicity and pharmacokinetics in non-human models
  • “proof of concept” and hypothesis generating from the point of view of the practicing clinician


  • “first in human” studies
  • administration of single sub-therapeutic doses of the study drug to a small number of subjects (<20)
  • gather preliminary data on pharmacodynamics and pharmacokinetics in humans
  • may also refer to exploratory trials and pilot studies for Phase 1 trials


  • test a new biomedical intervention for the first time in a small group of people (e.g. 20-100)
  • evaluate safety (e.g. determine a safe dosage range and identify side effects)
  • usually involves healthy volunteers


  • study an intervention in a larger group of people (several hundred)
  • determine dose requirements and efficacy (whether it works as intended)
  • further evaluate safety
  • involves healthy volunteers and/or patients
  • may be case series or randomised controlled trials


  • study the efficacy of an intervention in large groups of trial participants (from several hundred to several thousand)
  • compare the intervention to other standard or experimental interventions (or to non-interventional standard care)
  • monitor adverse effects and collect information that will allow the intervention to be used safely


  • post-marketing surveillance studies
  • monitor the effectiveness of the approved intervention in the general population
  • collect information about rare adverse effects associated with widespread use over longer periods of time
  • may or may not be mandated by regulatory bodies

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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