The purpose of this study is to evaluate safety, tolerability, and pharmacodynamics of MK-5475 after administration of multiple doses to participants with COVID-19 pneumonia. The primary hypothesis is that MK-5475 when administered to participants with COVID-19 pneumonia and hypoxemia improves arterial oxygenation as measured by the ratio of blood oxygen saturation to fraction of inspired oxygen (SpO2/FiO2 ratio) compared to placebo.
Drug: MK-5475
MK-5475 administered at a dose of 180 µg or ≤360 µg QD via inhalation
Drug: Placebo
MK-5475-matching placebo administered QD via inhalation
Inclusion Criteria:
- Has virologically confirmed COVID-19 requiring hospital admission.
- Has respiratory symptoms including cough and dyspnea
- Requires supplemental oxygen therapy
- Male participant is abstinent from heterosexual intercourse or agrees to use
contraception during the intervention period and for at least 14 days, corresponding
to time needed to eliminate study intervention(s) (example, 5 terminal half-lives
after the last dose of study intervention)
- Female participant is not a woman of childbearing potential (WOCBP) or is a WOCBP who
is abstinent from heterosexual intercourse or using contraception during the
intervention period and for at least 14 days, corresponding to time needed to
eliminate study intervention(s) (example, 5 terminal half-lives after the last dose of
study intervention)
Exclusion Criteria:
- Has pre-existing medical conditions of any nature which are immediately pre-terminal
such as death or limitation of life-sustaining therapy is expected to be imminent
- Requires or is expected to require invasive mechanical ventilation
- Requires or is expected to require noninvasive mechanical ventilation
- Has any issue which would prohibit them from effective use of the MK-5475 inhaler
- Hypoxemia which is explained by any condition other than COVID-19, example,
preexisting cardiac or pulmonary disease
- Has severe hepatic impairment (meets Child-Pugh Class C criteria)
- Has severe renal impairment and/or requirement for renal dialysis
Medical Director, Study Director
Merck Sharp & Dohme LLC