Efficacy and Safety of GSK3923868 Inhalation Powder, During Experimental Human Rhinovirus Infection in Participants With Mild Asthma

Inclusion criteria

• All Participant aged between 18 to 65 years of age (inclusive).
• Participants with a diagnosis of asthma.
• A screening pre-bronchodilator FEV1 greater than or equal to (≥) 65 percentage (%) predicted normal value.
• Positive Methacholine challenge test, defined as ≥ 20% fall in FEV1 at a methacholine concentration less than or equal to (≤) 16 milligram/milliliter (mg/mL) at Screening.

If the methacholine challenge test is negative or the participant is unable to perform this test, bronchodilator reversibility is allowed as an alternative, assessed as follows:

• Positive bronchodilator reversibility test, defined as an increase in FEV1 >12% and >200 mL from baseline, 10 to 15 minutes after administration of 400 micrograms (mcg) salbutamol (or equivalent).
• Participants with positive skin prick test.
• The HRV-16 neutralization antibody assay indicates that the participant will be susceptible to HRV-16 infection.
• Participants with controlled asthma, using short-acting beta agonist (SABA) or intermittent inhaled corticosteroid (ICS) or ICS/ long-acting beta agonist (LABA) therapy.
• Male and female- A female participant is eligible to participate if she is not pregnant or breastfeeding.
• Participant capable of giving signed informed consent.

Exclusion criteria

All participants:

• Any asthma exacerbation requiring systemic corticosteroids within 8 weeks of admission, or that resulted in overnight hospitalization requiring additional treatment for asthma within 3 months of admission.
• History of life-threatening asthma, defined as any asthma episode that required admission to a high-dependency or intensive therapy unit.
• The presence of concurrent significant pulmonary diseases, other than asthma, including bronchiectasis, pulmonary fibrosis, bronchopulmonary dysplasia, chronic bronchitis, emphysema, chronic obstructive pulmonary disease, or other significant respiratory abnormalities.
• Any significant abnormality altering the anatomy of the nose in a substantial way or nasopharynx that may interfere with the study.
• Any clinically significant history of epistaxis (large nosebleeds) within the last 3 months of admission and/or history of being hospitalized due to epistaxis on any previous occasion.
• Any nasal or sinus surgery within 3 months of admission with any acute illness, including a common cold or other respiratory tract infection within 6 weeks before admission.
• Any major illness or hospitalization within 6 months before admission to the unit.
• Lifetime history of anaphylaxis or severe allergic reaction or significant intolerance to any food or drug.
• Fridericia's QT correction formula (QTcF) >450 millisecond (msec) on Day -1 based on the average of triplicate ECGs.
• Evidence of vaccinations within the 4 weeks prior to the planned date of viral challenge.
• Intention to receive any vaccination before the last day of follow up.
• Prior participation in another Human Viral Challenge study with a respiratory virus in the preceding 12 months.
• Positive pathogen screen for respiratory tract infection
• History of regular use of tobacco or nicotine-containing products.
• Sensitivity to any of the study interventions, or components thereof, or drug or other allergy that contraindicates participation in the study.