Vitiligo is personal.

If you’re exploring your treatment options, we invite you to learn more about the Tranquillo 2 clinical trial. 

For people with vitiligo, skin care can mean a lot of different things. However you support your skin and whatever your relationship is with it, we want to meet you there.  

By participating in the Tranquillo 2 clinical trial, you will help us learn if a once-daily investigational pill is effective in treating vitiligo. Currently, there are no approved oral medications for nonsegmental vitiligo. That's why we're working to advance a potential medicine for people with vitiligo across the globe. 

Who may participate

Joining a clinical trial is an important and personal decision. We thank you for considering participation as an option that may be right for you.

You might be able to participate in this trial if you:

  • Have had nonsegmental vitiligo for at least three months
  • Have either active or stable vitiligo
  • Have vitiligo on the face and body


Nonsegmental vitiligo


18+ years


Male or Female

Each clinical study has its own guidelines for who can participate, called eligibility criteria. However, only the research study staff can determine if you qualify to enroll in the study.

Get started — See if you may qualify

A first step as you consider this study is to answer a 1-minute questionnaire about your health and medical history. If your answers show the study might be a good fit for you, you may choose to be referred to a study clinic that you select.

You will then be asked to provide your contact information for a study representative to contact you and discuss the next steps. If you’re interested, they will do a more detailed review of your medical history to see if you are able to participate. Only the study staff can determine if you meet the study’s eligibility criteria and are able to enroll in the study.

Your answers to these initial questions will only be linked to you if your responses indicate that you may be eligible to participate in this study and you choose to share your contact information with the study team. Pfizer study team members and our partners will have access to reports containing aggregated data that will not be directly linked back to you.

What to expect

If this trial is a good fit for you and you agree to take part, you will receive either the study medicine or a placebo. A placebo does not have any medicine in it, but it looks just like the medication being studied. In this trial, there is a greater chance of receiving the study medicine than the placebo.

Length of study treatment

Up to 26 months

Number of study visits

Up to 17

Long-term follow up

Approximately four weeks

An important contribution

Whether you choose to take part for yourself, or to potentially open doors to treatment for other people with vitiligo, you and your skin have the power to advance science.

An important contribution

Portrait of father and daughter at home
Portrait of father and daughter at home

Frequently asked questions

What is vitiligo?

Nonsegmental vitiligo is defined as an autoimmune condition. This means the immune system attacks healthy cells; in this case, pigment (or color)-producing cells called melanocytes. 

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How does the study medicine work?

The study medicine blocks the signals in the body believed to cause vitiligo. 

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Are there any risks associated with the study medicine?

All clinical trials have possible risks. The known risks of taking part in this phase 3 study will be explained to you during the informed consent process. This happens before you decide whether to participate.

This medicine is already available for other health conditions and a lot of information has already been collected during the phase 1 & 2 studies. So, by joining this phase 3 clinical trial you're helping researchers better understand how well this study medicine may work in vitiligo.

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What is drug development?

Drug development is the journey from an idea for a potential medicine all the way through to bringing that new medicine to patients who need it. The development process includes laboratory research and a series of clinical trials. Along the way, important information is collected about the potential medicine and how it affects clinical trial participants. If that information shows the potential medicine is safe and effective, clinical trial sponsors provide the information to regulatory authorities, which decide whether to approve the medicine’s use by patients.

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What are clinical trials?

Clinical trials (or research studies) are a type of medical research in which people volunteer to take part. Clinical trials commonly study how potential medicines and other medical treatments affect the participants.

All medicines and vaccines that become available today for use in patients are first tested in clinical trials involving hundreds to thousands of people.

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What happens in a clinical trial?

What happens in a clinical trial depends on the ‘protocol’. A protocol is a detailed plan that explains the purpose of the clinical trial and how it will be run. If you consider joining a clinical trial, these details will be explained to you as part of the informed consent process.
They include:

  • the length of the clinical trial
  • the study medicines, procedures, and tests in the clinical trial
  • the schedule of study activities
  • information about who can participate
  • how side effects will be tracked, managed, and reported
  • the rules that must be followed

A clinical trial may also have aspects such as randomization, placebo, or blinding.

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Who will oversee my care in a clinical trial? Can I continue to see my regular medical doctor?
  • As part of a clinical trial, your study-related medical care is provided by the study team at the location where you’re participating. This includes the principal investigator (or study doctor) — the healthcare professional who conducts and takes responsibility for the trial at that location — as well as other clinical study team members.
  • During your clinical trial, you may also continue to see your regular medical doctors for any care that is not related to the study. It is important for you to tell your study team about other conditions you might have, and to let them know which other doctors are caring for you. This helps the study team coordinate your overall care.
  • If you participate, the clinical trial will provide study-related medical care, and your regular medical doctors will address the other aspects of your health. Your regular medical doctors can also work with the study team to understand the details of the study and any impact it may have on your regular medical care.
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Are clinical trials safe?

All clinical trials have possible risks. The known and unknown risks of participating in a specific study will be explained to you during the informed consent process that happens before you decide whether to participate.

Clinical researchers must follow guidelines and regulatory requirements to help protect the rights, safety, and well-being of clinical trial participants. These include Good Clinical Practice (GCP). GCP is an international ethical and scientific quality standard for designing and conducting clinical trials.

There are also many entities that provide oversight of clinical trials. These include health authorities or regulators, institutional review boards and independent ethics committees, and data safety and monitoring boards.

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Who can join a clinical trial?

We encourage everybody to consider joining clinical trials. There are many types of clinical trials that study different aspects of health in people with a variety of backgrounds and conditions. Each clinical trial has its own criteria for who may participate. These are called eligibility criteria.

Eligibility criteria include things like your age, sex, overall health, type of condition, and your medical treatment history. As part of the steps to join a clinical trial, the study doctor will confirm whether you meet all eligibility criteria and are able to participate.

Participation in a clinical trial is always voluntary. The decision to join is personal, and it is yours.

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Is there any cost to participate in a clinical trial?

Pfizer generally covers the cost of the study medicines and procedures that are part of our clinical trials.

Pfizer is also committed to reimbursing participants for reasonable clinical trial-related expenses such as transportation, parking, and meals.

Because each study is different, we encourage you to ask the study team any questions you have. You can also refer to the informed consent document for the details about any costs for study participants and study-related reimbursement.

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