This study is seeking healthy participants who are: 1. Aged 18 to 65 years of age. All fertile participants must agree to use a highly effective method of contraception. 2. Male and female participants who are overtly healthy as determined by medical evaluation. This includes medical history, physical examination, blood pressure, pulse rate, standard 12-lead ECG (electrocardiogram), and laboratory tests. 3. BMI (body mass index) of 17.5 to 35 kg/m2; and a total body weight \>50 kg (110 lb). This study will consist of up to 2 cohorts (groups of participants).: Cohort 1 is a randomized, 2-part, crossover cohort. Part 1 has 3 periods. Periods 1 and 2 are to evaluate the safety and effects of sisunatovir. Participants will take sisunatovir tablets or placebo by mouth once every 12 hours. A placebo looks like the study medicine but does not contain any active medicine in it. Period 3 is an open label period to evaluate the food effect of the planned higher dose of sisunatovir. Participants will take the planned higher dose sisunatovir tablets every 12 hours. In Part 2, participants will take sisunatovir prepared in 4 different vehicles (water, infant formula, apple juice, and saline) to assess how palatable each form is. Participants will complete a questionnaire after tasting each form of sisunatovir. The palatability questionnaire will be completed for each vehicle, the questionnaire asks participants to assess each vehicle at 4 different time increments after tasting. At least 60 minutes will pass between tasting each vehicle. Period 4 may start after the last PK draw of Period 3. A minimum 7-day washout period will occur between the last dose of Periods 1 and 2 and the first dose of Periods 2 and 3. We will assess the safety of participants following each study period and doses and adjust the doses for subsequent study periods as needed. Cohort 2 is an optional cohort; the design of Cohort 2 is the same as Part 1 of Cohort 1. Dose levels studied in Cohort 2 will be determined after the completion of Cohort 1. Participants will take part in this study for approximately 2 months, excluding the screening period. During this time there are 3 separate 7-day in-patient stays at the study clinic and a follow-up phone call that takes place 28-35 days after the last dose of study medicine.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
QUADRUPLE
Enrollment
12
Sisunatovir is an orally administered RSV F-protein inhibitor being developed to target viral-host cell fusion for the treatment of adult and pediatric patients with RSV
Placebo for sisunatovir
Pfizer Clinical Research Unit - Brussels
Brussels, Bruxelles-capitale, Région de, Belgium
Number of Participants With Treatment Emergent Adverse Events (TEAEs)
An adverse event (AE) is any untoward medical occurrence in a participant or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. TEAEs were any AEs that occurred following start of treatment.
Time frame: From start of treatment to 28-35 days after last dose (maximum upto 66 days)
Number of Participants With Clinical Laboratory Abnormalities: Part 1
Laboratory tests included haematology (Monocytes \[10\^9/L\] increase: \> 1.2\* upper limit of normal \[ULN\] and Monocytes/Leukocytes \[percentage\] {%}:\> 1.2\* ULN); clinical chemistry (serum) included Alanine Aminotransferase (units per liter \[U/L\]):\> 3.0\* ULN and Bicarbonate (milliequivalents per liter) (mEq/L): \>1.1\* ULN and in urinalysis (urine Hemoglobin (Scalar) more than equal to (\>=) 1, urine Bilirubin (Scalar) \>= 1, Hyaline Casts (/Low power field \[LPF\]) \>= 1. Number of participants with any clinical laboratory abnormalities is reported in this outcome.
Time frame: Up to Day 5
Number of Participants With Newly Occurring Notable Abnormal Vital Signs: Part 1
Supine blood pressure (BP) was measured with the participant's arm supported at the level of the heart and recorded after approximately 5 minutes of rest. Pulse rate was measured in the brachial/radial artery. Notable abnormal vital sign categories included: Systolic BP: \<90 millimeter of mercury \[mmHg\]; Systolic BP change from baseline: maximum increase and decrease \>=30 mmHg; Diastolic BP \<50 mmHg; Diastolic BP change from baseline: maximum decrease and increase ≥20 mmHg; pulse rate \<40 and \>120 beats per minute. Number of participants with newly occurring notable abnormal vital sign (i.e. change in supine systolic BP \>=30 millimeter of mercury \[mmHg\] increase) is reported in this outcome measure.
Time frame: Up to Day 5
Number of Participants With Clinically Significant Changes in Electrocardiogram (ECG) Findings: Part 1
Standard 12-lead ECGs utilizing limb leads were used to measure PR interval, QT interval, QTc corrected using Fridericia's formula (QTcF), and QRS complex. ECG was performed after the participant had rested quietly for at least 5 minutes in a supine position. Clinical significance was determined by the investigator.
Time frame: Up to Day 7
Area Under the Curve From Time Zero to End of Dosing Interval (AUCtau) for Day 1: Part 1
Area under the concentration-time profile from time zero to time tau (the dosing interval), where tau = 12 hours for twice a day (BID) dosing.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1
Dose Normalized AUCtau (AUCtau [dn]) for Day 1: Part 1
AUCtau(dn) was calculated as AUCtau/Dose.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1
Maximum Observed Plasma Concentration (Cmax) for Day 1: Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1
Dose Normalized Maximum Plasma Concentration (Cmax [dn]) for Day 1: Part 1
Cmax(dn) was calculated as Cmax/Dose.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1
Time to Reach Maximum Observed Plasma Concentration (Tmax) for Day 1: Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1
Area Under the Curve From Time Zero to End of Dosing Interval (AUCtau) for Day 5: Part 1
Area under the concentration-time profile from time zero to time tau (the dosing interval), where tau = 12 hours for BID dosing.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 5
AUCtau(dn) for Day 5: Part 1
AUCtau(dn) was calculated as AUCtau/Dose.
Time frame: Pre-dose, 1, 2, 3,4, 5, 6, 8 and 12 hours post-dose on Day 5
Maximum Observed Plasma Concentration (Cmax) for Day 5: Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Cmax(dn) for Day 5: Part 1
Cmax(dn) was calculated as Cmax/Dose.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Time to Reach Maximum Observed Plasma Concentration (Tmax) for Day 5: Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Apparent Clearance (CL/F) for Day 5: Part 1
CL/F was calculated as Dose/AUCtau.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Observed Accumulation Ratio (Rac) for AUC for Day 5: Part 1
Rac for AUC was calculated as AUCtau Day5/AUCtau Day1.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1 and Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12 hours post-dose on Day 5
Observed Accumulation Ratio for Maximum Observed Plasma Concentration (Rac,Cmax) for Day 5: Part 1
Rac,Cmax was calculated as Cmax Day5/Cmax Day1.
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8 and 12 hours post-dose on Day 1 and Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Plasma Decay Half-Life (t1/2) for Day 5: Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Apparent Volume of Distribution (Vz/F) for Day 5: Part 1
Vz/F was calculated as Dose/(AUCtau \* kel \[Terminal phase rate constant\]).
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
AUCtau for Day 5: Evaluation of Food Effect (Sisunatovir 200 mg Fed Versus Fasted): Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12 hours post-dose on Day 5
Cmax for Day 5: Evaluation of Food Effect (Sisunatovir 200 mg Fed Versus Fasted): Part 1
Time frame: Pre-dose, 1, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36 and 48 hours post-dose on Day 5
Assessment of Overall Liking Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of overall liking by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated less overall liking.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Mouth Feel Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of mouth feel by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated worse mouth feel.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Bitterness Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of bitterness by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated more bitterness.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Tongue/Mouth Burn Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of tongue/mouth burn by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated more tongue/mouth burn.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Sourness Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of sourness by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated increase in sourness.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Saltiness Based on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of saltiness by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated more saltiness.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle
Assessment of Sweetness on Palatability Assessment Questionnaire: Part 2
Participants were required to answer the palatability attribute of sweetness by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), Participants were required to answer the palatability attribute of sweetness by providing a mark on the colour bar. The data was rescaled to a score ranging from 0 (good) to 100 (bad), where higher scores indicated more sweetness.
Time frame: 1 minute (immediately following dose), 5,10 and 20 minutes after tasting dose in each vehicle