Guide To Clinical Trials

What is a Clinical Trial?

Clinical trials are research studies performed in healthy volunteers or people with a specific illness or condition that are aimed at evaluating a new treatment or therapy. These studies are the primary way that researchers find out if a new treatment is safe and effective before it can be used to treat a specific disease or condition. Clinical trials are also used to learn if a new treatment is more effective or has less harmful side effects than the standard treatment.

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Understanding Clinical Trials

Clinical trials are conducted based on a protocol. A clinical trial protocol is a detailed plan for how the study will be conducted. It includes information about study treatment, eligibility criteria, rules to be followed, procedures, tests, schedule of activities and management of side effects.

Diversity in Clinical Trials

Inclusion is one of Gilead’s core values and encouraging diversity in our research programs helps us understand how our treatments affect all the populations who may benefit from the treatments we are studying. We believe that approach is especially important because the burden of many diseases often falls disproportionately on people from underrepresented and underserved communities. We are actively working to include a diverse group of participants, including underrepresented communities, across all our clinical trials.

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Types of Clinical Trials

If you decide to participate in a trial, it will be one of three kinds:

This is the experimental study that most likely comes to mind when you think about clinical trials. It is part of research needed before a treatment is approved for use by regulatory agencies. To test safety and effectiveness of the treatment, participants are assigned to a particular intervention (which may include placebo or other control) based on the protocol or research plan. An intervention could include drugs, vaccines, medical devices, medical procedures and/or behavioral interventions. A placebo looks like a treatment but does not have any medicine in it.

In this type of study, investigators observe participants throughout their existing, ongoing treatment or regular daily lives, and track their specific health outcomes over time. Unlike interventional trials, observational trial participants are not assigned to a specific group based on a research plan, such as being divided into treatment and placebo groups, but instead receive treatment as a part of their routine medical care. Observational study designs are used for reasons such as to better understanding a disease or potential associations for a disease that may be independent of any treatment (e.g., the effects of lifestyle on cardiac health, or ethical considerations).

This is a potential pathway for a patient with an immediately life-threatening condition or serious disease to gain access to an experimental treatment outside of clinical trials when no comparable or adequate alternative treatments are available. Expanded access is granted when a study is either ongoing or has completed, but before the drug is approved by a regulatory agency.

Clinical Trial Phases

Clinical trials typically go through a series of steps or phases. Each phase has a purpose. Before progressing to the next phase, regulatory agencies must approve both the safety and effectiveness of the medical intervention. The entire clinical trial process for an approved intervention takes an average of about 10 years, though some could take longer.

Phase 1

The main focus of Phase 1 studies is to examine an intervention’s safety and see how it interacts with the body. If the test is for a treatment, it can include different dosages.

  • Often includes less than 100 participants
  • Participants are healthy volunteers or patients with a specific condition
  • Analyzes how the intervention interacts with the body and any potential side effects
  • Takes on average about 2 years to complete, depending on the study design and outcomes

*Source: Informa Pharma Intelligence

Phase 2

Phase 2 studies focus on intervention effectiveness while also collecting data about safety and side effects.

  • Usually includes several hundred participants
  • Participants have a specific condition
  • Participants are sometimes given a placebo (inactive substance)
  • Helps better determine ideal dosage
  • Takes on average about 3 years to complete, depending on the study design and outcomes

*Source: Informa Pharma Intelligence

Phase 3

This is the last stage of research before an intervention can be submitted to regulatory authorities for review and approval for general public use. Phase 3 studies determine the effectiveness and safety of interventions compared to those already existing (if any).

  • Usually includes several hundred to several thousand participants
  • Participants have a specific condition
  • Can take several years to complete depending on the study design and outcomes

*Source: Informa Pharma Intelligence

Phase 4

Testing continues after an intervention is approved. Phase 4 studies determine the effectiveness and safety of interventions when used by the public in daily life, and collect additional data on benefits, risks, and quality of life.

  • Usually includes several thousand participants with a specific condition
  • Helps determine the optimal way to deliver the treatment
  • Can take many years to complete

*Source: Informa Pharma Intelligence

Clinical Trial Safety

It is understandable to be apprehensive about joining a clinical trial. However, we are dedicated to ensuring studies are designed and conducted following all regulatory and legal obligations for your safety. We value all individuals who elect to enroll in our clinical trials and work with clinicians to closely monitor the health of all participants throughout each study. Some measures that are in place to protect study participants include:

  • Informed Consent: A document given to those considering enrolling in a clinical trial by the research team. It describes the rights of a study participant and provides details about the trial, such as its purpose, duration, required procedures and key contacts. Risks and potential benefits are explained in the informed consent document.

  • Institutional Review Board/Ethics Committee (IRB/EC): A committee at hospitals and medical institutions whose purpose is to protect the rights and welfare of study participants recruited to take part in research activities at their locations. In accordance with the Food and Drug Administration (FDA) & the European Medicines Agency (EMA) regulations, an IRB/EC has the authority to approve, require modifications to or disapprove research trials.

  • Data Safety Monitoring Board: A group of qualified individuals that monitor the clinical study to ensure the safety of trial participants, as well as the validity and integrity of the study data.

Signing up for a clinical trial is completely voluntary, and you can withdraw any time if you change your mind. Following are some key things to keep in mind when considering enrolling in a study.

  • You cannot choose the intervention you receive, including the dosage level, whether you get a placebo, or whether you receive standard of care treatment as a comparator.

  • The experimental intervention might not be better than an available intervention or could have worse side effects.

  • Taking part in a trial may require more doctor visits than usual.