A study to learn how different preparations of Osivelotor taste and enter the blood with food or liquids, or with an antacid in healthy adults.

This study has two parts: Part 1 and Part 2. The purpose of Part 1 of this study is to learn how different preparations of the study medicine called osivelotor (PF-07940367) taste. The purpose of Part 2 of this study is to learn how the study medicine is taken up into the blood when mixed with:

• soft foods or liquids given on an empty stomach or
• with an acid-reducing agent in healthy adults.

This study is seeking participants who are:

• healthy females and males of 18 to 65 years of age.
• have a body mass index of 16 to 32 kilogram per meter squared.
• have a total body weight of more than 50 kilograms (110 pounds).

Participants in Part 1 of the study will receive the study medicine 4 times with at least 2-hour interval on day one. This study medicine will not be swallowed but will be placed in the mouth and spat out. The participants will then complete a short questionnaire 4 times over 20 minutes. All study medicines will be given in the study clinic.

Participants in Part 2 of the study will receive the study medicine up to 2 times. The first dose of the study medicine will be swallowed. The second dose the study medicine (if given) will not be swallowed but will be placed in the mouth and spat out for the taste questionnaire as above. All study medicines will be given in the study clinic.

In Part 1, participants will be involved in this study for up to 2 months. During this time, there will be a two-day stay in the study clinic. After leaving the clinic, study team will also call participants once over the phone. Woman who could become pregnant may need to visit the study clinic instead of receiving a phone call.

In Part 2, participants will be involved in this study for up to 4 months. During this time, there will be a seven-day stay in the study clinic. After leaving the clinic, the study team will also call participants 3 times over the phone. Woman who could become pregnant may need to visit the study clinic instead of receiving a phone calls.

In both parts blood and urine tests will be done, and blood pressures and heart traces taken. Also, contraception requirements will need to be followed to prevent pregnancy during the study.

Inclusion Criteria:

• Male and female participants aged 18 years (or the minimum age of consent in accordance with local regulations if >18 years) to 65 years (inclusive) at screening who are overtly healthy as determined by medical evaluation including a detailed medical history, complete physical examination (PE), including blood pressure (BP) and pulse rate (PR) measurement, 12-lead ECG (electrocardiogram) and clinical laboratory tests.
• Body mass index (BMI) of ≥16 to ≤32 kg/m2; Body weight ≥50 kg (110 lb).

Exclusion Criteria:

• Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
• Use of prescription or nonprescription drug, dietary and herbal supplements within 7 days or 5 half-lives (whichever is longer), with the exception of moderate or strong cytochrome P450 (CYP)3A inducers or inhibitors which are prohibited within 14 days plus 5 half-lives, prior to the first dose of study intervention.
• Current use of any prohibited concomitant medication(s) or participant unwilling/able to use a permitted concomitant medication(s).
• Previous administration with an investigational product (drug or vaccine) within 30 days (or as determined by the local requirement) or 5 half-lives preceding the first dose of study intervention used in this study (whichever is longer). Participation in studies of other investigational products (drug or vaccine) at any time during their participation in this study.
• For females, pregnancy, as indicated by a positive serum pregnancy test (serum) at screening and/or a positive pregnancy test (serum and/or urine) on Day -1 in women of childbearing potential.
• Screening supine BP ≥140 mm Hg (systolic) or ≥90 mm Hg (diastolic) for participants <60 years; and ≥150/90 mm/Hg for participants ≥60 years old, following at least 5 minutes of supine rest.
• Standard 12-lead ECG that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results (eg, QTcF [QTc corrected using Fridericia's formula] >450 ms, complete left bundle branch block (LBBB), signs of an acute or indeterminate-age myocardial infarction, ST-T interval changes suggestive of myocardial ischemia, second- or third- degree AV (atrioventricular) block, or serious bradyarrhythmias or tachyarrhythmias).
• Participants with defined abnormalities in kidney and liver laboratory tests at screening.

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.