NCT07660731 · Pfizer
A Study to Learn How Different Amounts of the Study Medicine Called PF-08103402 Are Tolerated and Act in the Body in Healthy Adults or Adults With Mild To-moderate Asthma
What this study is about
The purpose of this study is to learn about the safety of a new study medicine called PF-08103402 in healthy adults (do not have disease) and or in adults with mild-to-moderate asthma. This is the first time the study medicine is being given to people.
View original scientific description
The purpose of this study is to learn about the safety of a new study medicine called PF-08103402 in healthy adults (do not have disease) and or in adults with mild-to-moderate asthma. This is the first time the study medicine is being given to people. For Parts A, B, C, D and F, the study is seeking participants who: * Are healthy (do not have disease) males or females who can no longer have children, * Are 18 to 65 years old, * Have a body mass index (BMI) of 16 to 32 kilograms per meter squared and a body weight of more than 50 kilograms (110 pounds). Body mass index is a way to measure body fat by using a person's height and weight For Part A (optional group or cohort 3: Japanese participants only): * A body weight of more than 45 kilograms (100 pounds). * Have 4 biological Japanese grandparents who were born in Japan. For Part E only: * Adults with a documented history of asthma (confirmed by a doctor) for at least 12 months before entering the study. * Have a body mass index (BMI) of 16 to 35 kilograms per meter squared and a total body weight of more than 50 kilograms (110 pounds). The study has six parts: Part A, Part B, Part C, Part D, Part E and Part F. The study medicine will be taken as a suspension or tablet by mouth 1 time a day (except in Parts B and E where it will be taken 1 time a day for 14 days) at the study clinic. The study will help understand: * how the body processes the study medicine in healthy participants (Parts A and B), * how much of the study medicine gets into the bloodstream and if food affects the amount of study medicine in the blood in healthy participants (Part C), * how the study medicine is broken down and leaves the body in healthy participants (Optional Part D), * how the study medicine is processed in adults with mild-to-moderate asthma (Optional Part E), * if taking the study medicine together with another medicine affects how each medicine is processed by the body in healthy participants (Optional Part F). Participants will take part in the study for about 10 weeks (Parts A and F), 12 weeks (Part B), 9 weeks (Parts C and D), and 16 weeks (Part E). During this time, they will have 2 study visits at the study clinic and up to 28 overnight stays (Part A), 18 overnight stays (Parts B and E), 10 overnight stays (Part C), 11 overnight stays (Part D), and 16 overnight stays (Part F). The study team will also call participants 1 time over the phone at the end of the study to assess how they are doing. Study measurements will be taken by body examination, monitoring side effects, blood and urine tests, heart tests (ECG), vital signs (blood pressure and pulse), questionnaires (Parts C and E), stool samples (Part D only), and breathing tests (Part E only).
Interventions
DRUG
PF-08103402
Oral suspension (Parts A to F); Tablets (Parts C and F only)
DRUG
Placebo
Oral suspension (Parts A, B and E).
DRUG
Midazolam
Oral syrup
Primary outcome measures
Number of Participants with Treatment Emergent Adverse Events (TEAEs)
Time frame: Parts A: Up to Day 36; Part B and E: Up to Day 50
Part A: Cohorts 1, 2 and Cohort 3 (optional). Part B: Cohorts 4, 5, 6, and 7 and Cohort 8 (optional). Part E: Cohorts 11 (optional) and 12 (optional)
Number of Participants with Serious Adverse Events (SAEs)
Time frame: Parts A: Up to Day 36; Part B and E: Up to Day 50
Part A: Cohorts 1, 2 and Cohort 3 (optional). Part B: Cohorts 4, 5, 6, and 7 and Cohort 8 (optional). Part E: Cohorts 11 (optional) and 12 (optional)
Number of Participants With Clinically Significant Change From Baseline in Laboratory Abnormalities
Time frame: Parts A: Change From Baseline to Day 7; Part B and E: Change From Baseline to Day 17
Part A: Cohorts 1, 2 and Cohort 3 (optional). Part B: Cohorts 4, 5, 6, and 7 and Cohort 8 (optional). Part E: Cohorts 11 (optional) and 12 (optional)
Number of Participants With Clinically Significant Change From Baseline in Vital Signs
Time frame: Parts A: Change From Baseline to Day 7; Part B and E: Change From Baseline to Day 17
Part A: Cohorts 1, 2 and Cohort 3 (optional). Part B: Cohorts 4, 5, 6, and 7 and Cohort 8 (optional). Part E: Cohorts 11 (optional) and 12 (optional).
Number of Participants With Clinically Significant Change From Baseline in Electrocardiogram (ECG) Findings
Time frame: Parts A: Change From Baseline to Day 7; Part B and E: Change From Baseline to Day 17
Part A: Cohorts 1, 2 and Cohort 3 (optional). Part B: Cohorts 4, 5, 6, and 7 and Cohort 8 (optional). Part E: Cohorts 11 (optional) and 12 (optional).
Area under the curve from time zero to extrapolated infinite time (AUCinf) if data permit, otherwise (AUClast) in the fasted state
Time frame: Pre-dose (Hour 0) and at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12 hours post-dose on Day 1
Part C: Cohort 9
Maximum observed plasma concentration (Cmax) in the fasted state
Time frame: Pre-dose (Hour 0) and at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12 hours post-dose on Day 1
Part C: Cohort 9
Total recovery of drug-related material in urine and feces separately, and both routes combined, expressed as a percent of total dose administered
Time frame: Pre-dose (Hour 0) and at 1.5, 2, 3, 4, 6, 8, 12 hours post-dose on Day 1 and at 24 hours post-dose (Day 2)
Part D: Cohort 10 (optional)
Maximum observed plasma concentration (Cmax)
Time frame: Pre-dose (Hour 0) and at 0.5, 1, 2, 4, 6, 8, 12 hours post-dose on Day 1 and at 24 hours post-dose (Day 2)
Part F: Cohort 13 (optional)
Area under the curve from time zero to extrapolated infinite time (AUCinf) if data permit, otherwise AUClast
Time frame: Pre-dose (Hour 0) and at 0.5, 1, 2, 4, 6, 8, 12 hours post-dose on Day 1 and at 24 hours post-dose (Day 2)
Part F: Cohort 13 (optional)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- (Parts A, B, C, D and F):
- Are males or females who can no longer have children,
- Are 18 to 65 years old,
- Have a body mass index (BMI) of 16 to 32 kilograms per meter squared and a total body weight of more than 50 kilograms (110 pounds). For Part A (Optional group or cohort 3: Japanese participants only):
- A total body weight of more than 45 kg (100 pounds).
- Have 4 biological Japanese grandparents who were born in Japan. For Part E only: Adults with a documented doctor's-diagnosis history of asthma for at least 12 months before entering the study. 1\. Have a body mass index (BMI) of 16 to 35 kilograms per meter squared and a total body weight of more than 50 kilograms (110 pounds). Key
Exclusion criteria
- Evidence or history of clinically significant medical conditions.
- History of human immunodeficiency virus (HIV) infection, hepatitis B, or hepatitis C; positive testing for HIV, hepatitis B surface antigen (HBsAg), or hepatitis C antibody (HCVAb).
- History of alcohol abuse or binge drinking and/or any other illicit drug use or dependence within 6 months of Screening.
- Participation in studies of other investigational products (drug or vaccine) at any time during their participation in this study.
- Any history of parasitic infection requiring treatment within 28 days prior to screening.
- Positive tuberculosis infection test result.
- Part C only: Evidence or history of conditions interfering with the ability to taste.
- Part D only: History of irregular bowel movements.
- Part E only: Evidence of lung disease(s) other than asthma.
- Part E only: Asthma exacerbation within 3 months prior to screening.
- Part F only: History of acute narrow-angle glaucoma, untreated open-angle glaucoma, sleep apnea, respiratory insufficiency, myasthenia gravis or adverse reaction to midazolam or other benzodiazepines.
Where
- New Haven, Connecticut
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 29, 2026 · Source of record for eligibility and locations