The change in Reactive Hyperemia Peripheral Index (RHI) as measured by Arterial Tonometry. The Reactive Hyperemia Index (RHI) is calculated as the ratio of post- to pre-occlusion peripheral arterial tone signals on the occluded side, normalized to the control side, and further adjusted for baseline vascular tone. RHI is automatically measured by the EndoPAT 2000 software. According to the manufacturer, an RHI value greater than 1.67 is considered normal, while a lower value indicates endothelial dysfunction and is associated with an increased risk of cardiovascular events.

To demonstrate a reduction in lung function decline for ifetroban compared to placebo over 52 weeks.

Percentage of subjects with one or more treatment emergent adverse event

Sinonasal Outcome Test-22 (SNOT-22) score is a scale with a minimum score of 0 and a maximum score of 110 based on the presence and severity of symptoms and outcomes of rhinosinusitis. Higher scores indicate worse symptoms and/or outcomes.

Incidence is measured as the total number of adverse events reported during the treatment and follow-up period for each treatment group.

The severity of each event is reported by the investigator according to the following protocol/CTCAE definitions: Grade 1-Mild; asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not indicated; Grade 2-Moderate; minimal, local or noninvasive intervention indicated; limiting age-appropriate instrumental activities of daily living; Grade 3-Severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; limiting self-care activities of daily living; Grade 4-Life-threatening consequences; urgent intervention indicated; Grade 5-Death related to adverse event.

Safety is measured using AEs, including clinical significant changes in vital signs, laboratory test abnormalities and clinical tolerability of ifetroban.

Plasma concentrations of ifetroban and its major active metabolite were measured at Baseline and Study Hours 1, 2, 4, 8, 12, 24, 48, 49, 50, 52, 56, 60, and 72 to determine the Pharmacokinetic parameters.

Plasma concentrations of ifetroban and its primary active metabolite were measured at Baseline and Study Hours 1, 2, 4, 8, 12, 24, 48, 49, 50, 52, 56, 60, and 72 to determine the Pharmacokinetic parameters.

Plasma concentrations of ifetroban and it's major active metabolite were measured at Baseline and Study Hours 1, 2, 4, 8, 12, 24, 48, 49, 50, 52, 56, 60, and 72 to determine the Pharmacokinetic parameters.