Pharmacokinetic Effects of QTI571 on Sildenafil and Bosentan in Pulmonary Arterial Hypertension Participants

AUCtau was the area under the curve calculated to the end of the dosing interval, tau. The effect of co-administration of imatinib at two doses (200 and 400 mg) on the pharmacokinetics of bosentan was performed on dose normalized AUCtau of bosentan. A mixed effects linear model was fitted to the log-transformed PK parameters. This model included treatment (i.e., dose of imatinib) as a fixed effect, and participant as a random effect. Estimates for the treatment differences and associated 90% confidence intervals were obtained from the above model. These estimates and confidence intervals were then "back-transformed" to the original scale, giving, for each dose level of imatinib, the ratio of imatinib + co-administered sildenafil and bosentan (test) relative to the co-administered drugs alone (sildenafil + bosentan) (reference).

AUCtau was the area under the curve calculated to the end of the dosing interval, tau. The effect of co-administration of imatinib at two doses (200 and 400 mg) on the pharmacokinetics of sildenafil was performed on dose normalized AUCtau of sildenafil. A mixed effects linear model was fitted to the log-transformed PK parameters. This model included treatment (i.e., dose of imatinib) as a fixed effect, and participant as a random effect. Estimates for the treatment differences and associated 90% confidence intervals were obtained from the above model. These estimates and confidence intervals were then "back-transformed" to the original scale, giving, for each dose level of imatinib, the ratio of imatinib + co-administered sildenafil and bosentan (test) relative to the co-administered drugs alone (sildenafil + bosentan) (reference).

Cmax was the maximum (peak) observed plasma, blood, serum, or other body fluid drug concentration after dose administration. The effect of co-administration of imatinib at two doses (200 and 400 mg) on the pharmacokinetics of bosentan was performed on dose normalized Cmax of bosentan. A mixed effects linear model was fitted to the log-transformed PK parameters. This model included treatment (i.e., dose of imatinib) as a fixed effect, and participant as a random effect. Estimates for the treatment differences and associated 90% confidence intervals were obtained from the above model. These estimates and confidence intervals were then "back-transformed" to the original scale, giving, for each dose level of imatinib, the ratio of imatinib + co-administered sildenafil and bosentan (test) relative to the co-administered drugs alone (sildenafil + bosentan) (reference).

Cmax was the maximum (peak) observed plasma, blood, serum, or other body fluid drug concentration after dose administration. The effect of co-administration of imatinib at two doses (200 and 400 mg) on the pharmacokinetics of sildenafil was performed on dose normalized Cmax of sildenafil. A mixed effects linear model was fitted to the log-transformed PK parameters. This model included treatment (i.e., dose of imatinib) as a fixed effect, and participant as a random effect. Estimates for the treatment differences and associated 90% confidence intervals were obtained from the above model. These estimates and confidence intervals was then "back-transformed" to the original scale, giving, for each dose level of imatinib, the ratio of imatinib + co-administered sildenafil and bosentan (test) relative to the co-administered drugs alone (sildenafil + bosentan) (reference).

An adverse event was the appearance or worsening of any undesirable sign, symptom, or medical condition that occurred after starting the study drug even if the event was not considered to be related to study drug. Number of participants with AEs were reported by treatment period.