It can take up to 10 years to develop a new medication. During this process plenty of information to learn if and how a new medication works need to be gathered before doctors are allowed to prescribe it. This information is collected in clinical research studies (also known as clinical trials) that test investigational medications (also known as study drugs) in humans. Each study follows a plan (or “protocol”) that has been reviewed and approved by various groups of people, including health authorities, like the Food and Drug Administration (FDA) in the United States, as well as scientists, doctors, lawyers, and members of the public.

Clinical trial participants can play a more active role in their health care, gain access to new research treatments before they are widely available and help others by contributing to medical research.

There are four phases of clinical trials. The trials at each phase have a different purpose and help answer different questions.

• Phase I – test a new drug or treatment in a small group of people for the first time in order to evaluate the treatment’s safety, how much can be given safely, and to identify possible side effects from the treatment.
• Phase II – typically test the treatment in a larger group of people in order to see if the treatment is effective and to further evaluate the safety of the treatment. Patients are usually given either active medication or placebo without knowing which one they are taking.
• Phase III – typically test the treatment in a large group of people to confirm that the treatment is effective, monitor side effects, compare the treatment to other commonly used treatments, and collect additional information which should help allow safe use of the treatment. Again, patients are usually given either active medication or placebo without knowing which one they are taking.
• Phase IV – are usually studies that are conducted once a drug is on the market and establish additional information about the treatment’s risks, benefits, and best use of the treatment.

The number of people included in each stage of a trial increases from one stage to the next, with the total number in a given trial depends on the type of disease the trial is addressing. For example, a clinical trial for a rare disease like PFIC would enroll far fewer patients than a clinical trial for a common condition that impacts millions of people, such as heart disease or diabetes.

An investigational medication is a drug that is not approved for marketing by the health authorities. It is generally only available for use in clinical research studies to determine its safety and effectiveness.

Approximately 3,000 people in the United States and 5,000 people in Europe are affected by PFIC. Approximately 60% of PFIC patients are estimated to be PFIC2.

There is currently no therapy approved for PFIC and available medical approaches have limited efficacy. Under current standard of care, patients often require a liver transplant and are at higher risk of many serious health issues.

Mirum Pharmaceuticals Inc. is a clinical-stage therapeutics company developing a novel approach for treating liver diseases, with an immediate focus on rare pediatric conditions. The company’s lead product candidate, maralixibat, is an investigational orally-administered drug with an established safety profile and efficacy data in several indications, including Alagille syndrome (ALGS) and progressive familial intrahepatic cholestasis (PFIC). Mirum is dedicated to bringing innovative medicines to patients as quickly and efficiently as possible. For more information, visit www.mirumpharma.com.