Trial results
AI generated results summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
According to the results reported on ClinicalTrials.gov, this trial looked at two investigational medicines — PF-06651600 and PF-06700841 — compared to a placebo (an inactive treatment) in people with alopecia areata, a condition that causes patchy or complete hair loss on the scalp. A total of 142 people took part in the first 24-week treatment stage: 48 received PF-06651600, 47 received PF-06700841, 24 received a placebo matched to PF-06651600, and 23 received a placebo matched to PF-06700841. The trial then continued into two further stages — a single-blind extension and a cross-over extension — where smaller numbers of participants continued. The main thing being measured was change in scalp hair loss using a standard scoring tool called SALT, where a score of 0 means no hair loss and 100 means complete scalp hair loss, and a higher positive change from the starting score means more hair had grown back. The reported data shows that after 24 weeks, the placebo group had an average improvement of about 1.4 points on the SALT scale from their starting score. By comparison, the PF-06651600 group had an average improvement of about 32.5 points, and the PF-06700841 group had an average improvement of about 50.6 points. In a smaller sub-group of people who had total scalp hair loss or total body hair loss at the start, the reported data shows similar patterns: the placebo group averaged roughly 1.8 points of improvement, PF-06651600 around 27.6 points, and PF-06700841 around 48.4 points. The trial also tracked unintended medical events (called adverse events) and unusual laboratory test results across all stages. The reported data shows that during the extension stages, varying numbers of participants across the different treatment groups experienced adverse events or laboratory abnormalities — for example, during the single-blind extension, the numbers reporting adverse events ranged from 3 to 12 participants depending on which group they were in. The data was not reported in a way that allows straightforward comparison of all groups side by side for these measures. These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.
View full results on ClinicalTrials.gov ↗ · Read the linked publication on PubMed (PMID 42481842) ↗
These are the results as reported to ClinicalTrials.gov, not medical advice. Verify independently with the trial site and discuss what they mean for you with your doctor.
Phase 2 Alopecia Areata Trial, Completed
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You are between 18 and 75 years old (inclusive) at the time you sign the consent form
- You have been diagnosed with moderate to severe alopecia areata (a condition causing significant hair loss)
Who may not be able to join:
- You have HIV or tested positive for HIV during screening
- You are infected with hepatitis B or hepatitis C
- You have signs of an active, hidden, or not fully treated tuberculosis (TB) infection
- You have received certain medications that deplete cells in the immune system within the last 6 months before starting the trial
- You have taken JAK inhibitor medications or other biologic treatments within the last 12 weeks before starting the trial
- You have participated in another clinical trial involving an experimental drug within the last 8 weeks before starting the trial
- You have received a live or weakened live vaccine within the last 6 weeks before starting the trial
- You have taken oral medications that suppress the immune system within the last 4 weeks before starting the trial
- You have had light therapy (UV-based) treatments within the last 4 weeks before starting the trial
- You have regularly used a tanning booth more than twice a week within the last 4 weeks before starting the trial
- You have used topical (applied to the skin) treatments that could affect hair loss within the last 2 weeks before starting the trial
- You have used herbal medicines with unknown effects or known benefits for alopecia areata within the last 2 weeks before starting the trial
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
Contact this trial
Principal Investigator: Pfizer CT.gov Call Center, Pfizer
Australian sites
Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
10 site(s) in Australia. Confirm current status and contact details directly with the trial site.
Primary endpoints
Change From Baseline in Severity of Alopecia Tool (SALT) Score at Week 24; Number of Participants With Treatment-emergent Adverse Events (All-causality and Treatment-related) - Single-Blind Extension (SBE) Period; Number of Participants With Treatment-emergent Adverse Events (All-causality and Treatment-related) - Cross-Over Extension (COE) Period; Number of Participants With Laboratory Abnormalities During SBE Period; Numbers of Participants With Specific Clinical Laboratory Abnormalities During COE Period
Can't join this trial?
Data last synced from ClinicalTrials.gov: 26 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.