after joining, you will undergo a series of initial examinations that include a review of your medical history, a lung function test called fev1 (forced expiratory volume in one second), and questionnaires that measure breathing difficulty and quality of life.

these assessments establish your baseline values, which will be used to compare later results.

based on the baseline information, you will be randomly assigned to receive either pf-07275315 or a placebo.

the randomization process ensures that the assignment is unbiased and that the study groups are comparable.

you will receive a subcutaneous injection (injection under the skin) of the study medication or matching placebo.

the dose is defined by the study protocol and is administered at regular intervals (for example, every four weeks) for the duration of the treatment period.

in phase 2 the treatment period lasts up to week 24, while in phase 3 it extends up to week 52.

you will attend scheduled clinic visits (for example, at weeks 4, 12, 24 and, in phase 3, at weeks 36 and 52).

at each visit, lung function tests (fev1 and other measurements), questionnaires, and safety evaluations such as blood tests and vital‑sign checks will be performed.

any side effects or adverse events that occur will be recorded.

at each follow‑up visit you will receive another dose of the assigned study medication or placebo, continuing the schedule until the end of the designated treatment period.

the injection schedule remains the same throughout the study.

at the end of the treatment period (week 24 for phase 2, week 52 for phase 3) a comprehensive evaluation is performed.

this includes the final lung function test, repeat questionnaires, and a complete safety review.

the results are compared with the baseline measurements to determine the effect of the study medication.

after the final assessment, study medication administration stops.

the collected data are used for analysis, and no further study‑related procedures are required.