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Clinical Trial Types

A clinical trial or clinical study is carefully designed and conducted as observational studies in human volunteers to answer precise health questions.


  • Interventional trials determine whether experimental treatments or new ways of using known therapies are safe and effective under controlled environments
  • Observational trials monitor the health of large groups of volunteers through their normal activities over a set timeframe without an investigational therapy being administered
  • Screening trials test the best way to detect certain diseases or health conditions.
  • Quality of Life trials (or Supportive Care trials) explore ways to improve comfort and the quality of life for individuals with a chronic illness
  • Expanded Access is the use of an investigational new drug or IND outside of a clinical trial for patients managing serious diseases or conditions.

Clinical trials are the backbone of medical innovation and are considered one of the fastest and safest ways to realize new treatments that improve health and save lives.



Clinical trials are conducted in phases as defined by the FDA. The trials at each phase have a different purpose and help scientists answer different questions:

  • Phase I trials test an experimental drug, vaccine or device in a small group of people (20-80) to evaluate safety, determine safe dosage ranges, and identify side effects.
  • Phase II trials involve larger groups of people (100-300) and further gauge safety and efficacy.
  • Phase III trials are usually large studies (1,000-3,000) comparing the experimental drug or vaccine to a placebo or standard treatment. This is done in order to confirm effectiveness, how best to use, and further monitor side effects.
  • Phase IV trials also known as Post Market Studies (PMS) are done to provide additional information about the best use of the drug.

What are the benefits and risks for participants in a clinical trial?


  • Receive cutting edge treatments not normally delivered as “standard of care”
  • Receive new treatments or care at no cost
  • Access new treatments to combat the most challenging of conditions
  • Access to new treatment pipelines not readily available to the public
  • Possess greater control over healthcare options and decisions
  • Help others and save lives by being an integral part of medical research and innovation


  • The treatment may not be effective for the participant.
  • Potential side effect may occur that can be unpleasant, serious or even life-threatening
  • Maybe assigned to control group and/or receive placebo in blinded studies
  • Trials may demand more of a patient’s time and attention in comparison to conventional clinics or physicians. Examples of this include but are not limited to:
    • Multiple trips to the study site
    • Additional treatments
    • Hospital stays
    • Complex dosage requirements
    • Daily/Weekly/Monthly journal charting
    • Use of remote monitoring devices (i.e. wearable)

Why offer clinical trials to your patients?

Benefits to the physician and/or practice:

  • Patient Care – Provide additional care options to include treatments not readily available to conventional practitioners or practices
  • Medical Innovation – Take part in advancing healthcare innovation by supporting the R&D phase
  • Drug pricing – Contribute to lowering drug prices, as efficient sourcing of patients will yield savings of up to 40% (GS report) in clinical trial costs.
  • Expanded Access — Have relationships to source and access IND’s for the rare patients in need of life saving treatments

How is the safety of the participant protected?

The primary role of the research investigator is to ensure the safety of the participants. In addition, the independent institutional review board that monitors the study has a primary role in protecting the safety of study participants. The ethical and legal codes that govern medical practice also apply to clinical trials. In addition, most clinical research is federally regulated with built in safeguards to protect the participants.

What should potential participants consider before enrolling in a trial?

Prospective patients and their providers should know as much as possible about the trial in question and feel comfortable asking the trial’s administrators about:

  • trial endpoints
  • measurable outcome
  • expected interventions
  • potential healthcare needs during or after the closing of the trial
  • trial flow or event timeline
  • potential associated costs, if any

Information can be found in the protocol forms and/or the informed consent document/s. However, additional questions may arise, and info for the following should be obtained before electing to join a trial or advise a patient to do so:

  • What is the purpose of the study?
  • Who is going to be in the study?
  • Why do researchers believe the new treatment being tested may be effective?
  • Has it been tested before?
  • What kinds of tests and treatments are involved?
  • How do the possible risks, side effects, and benefits in the study compare with my current treatment?
  • How might this trial affect my daily life?
  • How long will the trial last?
  • Will hospitalization be required?
  • Who will pay for the treatment?
  • Will I be reimbursed for other expenses?
  • What type of long-term follow up care is part of this study?
  • How will I know that the treatment is working?
  • Will results of the trials be provided to me?
  • Who will be in charge of care?

Can a participant continue to work with a primary health care provider while in a trial?

Yes, and is even encouraged to do so! Most clinical trials provide short-term treatments related to a designated illness or condition, but do not provide extended or complete primary health care. In addition, by having the health care provider work with the research team, the participant can ensure that other medications or treatments will not conflict with the protocol or cause adverse reactions to the patient.

Can a participant leave a clinical trial after it has begun?

A participant can leave a clinical trial, at any time. When withdrawing from the trial, the participant should let the research team know about it, and the reasons for leaving the study.

Who sponsors clinical trials?

A sponsor is a company, institution, organization, or person who oversees or pays for the administration, data collection, and analysis of a clinical trial. Examples of sponsors include but are not limited to:

  • individuals such as physicians
  • medical institutions
  • foundations
  • volunteer or community groups
  • private companies such as:
    • pharmaceutical
    • biotechnology
    • or medical device companies
  • federal agencies such as:
    • the National Institutes of Health (NIH)
    • Department of Defense (DOD)
    • the Department of Veteran’s Affairs (VA)

Do clinical trial participants need health insurance?

Clinical trial sponsorships cover all costs including for the treatment and care of participating patients, so no need for insurance at all! In fact, most studies even pay a modest amount to the patients for their time and willingness to volunteer.