Outcome
Type |
Measure |
Description |
Time frame |
Safety issue |
Primary |
Cough Reflex Sensitivity to Capsaicin Measured by Maximal Cough Response (Emax) |
The effect of single doses of 50 mg and 300 mg gefapixant on cough reflex sensitivity to challenge with capsaicin was assessed in male and female healthy participants and participants with chronic cough. Capsaicin-evoked cough challenge was performed 2 hours post-dose in Periods 1 and 2. The maximal cough response (Emax) to capsaicin was assessed. For capsaicin challenge, doubling concentrations from 0.49 µM to 1000 µM were prepared by dilution of stock solutions with saline, and were administered by inhalation. The number of explosive cough sounds occurring within the first 15 seconds after inhalation were recorded. Nonlinear mixed-effects modeling was used to estimate the Emax. Population pharmacodynamic modeling was performed in NONMEM 7.3. Data exploration, goodness-of-fit plots, statistical analyses, and simulations were performed in Matlab R2015a. Note: All values presented in this table are model-based. |
2 hours post-dose |
|
Primary |
Cough Reflex Sensitivity to Capsaicin Measured by the Tussive Concentration Required to Achieve 50% of Emax (ED50) |
The effect of single doses of 50 mg and 300 mg gefapixant on cough reflex sensitivity to challenge with capsaicin was assessed in male and female healthy participants and participants with chronic cough. Capsaicin-evoked cough challenge was performed 2 hours post-dose in Periods 1 and 2. The concentration of capsaicin required to induce 50% of the Emax (ED50) was assessed. For capsaicin challenge, doubling concentrations from 0.49 µM to 1000 µM were prepared by dilution of stock solutions with saline, and were administered by inhalation. Nonlinear mixed-effects modeling was used to estimate the ED50. Population pharmacodynamic modeling was performed in NONMEM 7.3 using Laplace estimation method. Data exploration, goodness-of-fit plots, statistical analyses, and simulations were performed in Matlab R2015a. Note: All values presented in this table are model-based. |
2 hours post-dose |
|
Secondary |
Cough Reflex Sensitivity to Adenosine Triphosphate (ATP) Measured by Maximal Cough Response (Emax) |
The effect of single doses of 50 mg and 300 mg gefapixant on cough reflex sensitivity to challenge with adenosine triphosphate (ATP) was assessed in male and female healthy participants and participants with chronic cough. ATP-evoked cough challenge was performed 2 hours post-dose in Periods 3 and 4. For ATP challenge, doubling concentrations from 0.227 µmol/mL to 929 µmol/mL were prepared from ATP powder dissolved in saline, and were administered by inhalation. The number of explosive cough sounds occurring within the first 15 seconds after inhalation were recorded. Nonlinear mixed-effects modeling was used to estimate the Emax. Population pharmacodynamic modeling was performed in NONMEM 7.3. Data exploration, goodness-of-fit plots, statistical analyses, and simulations were performed in Matlab R2015a. Note: All values presented in this table are model-based. |
2 hours post-dose |
|
Secondary |
Cough Reflex Sensitivity to ATP Measured by the Tussive Concentration Required to Achieve 50% of Emax (ED50) |
The effect of single doses of 50 mg and 300 mg gefapixant on cough reflex sensitivity to challenge with ATP was assessed in male and female healthy participants and participants with chronic cough. ATP-evoked cough challenge was performed 2 hours post-dose in Periods 3 and 4. The concentration of ATP required to induce 50% of the Emax (ED50) was assessed. For ATP challenge, doubling concentrations from 0.227 µmol/mL to 929 µmol/mL were prepared by dilution of stock solutions with saline, and were administered by inhalation. Nonlinear mixed-effects modeling was used to estimate the ED50. Population pharmacodynamic modeling was performed in NONMEM 7.3 using Laplace estimation method. Data exploration, goodness-of-fit plots, statistical analyses, and simulations were performed in Matlab R2015a. Note: All values presented in this table are model-based. |
2 hours post-dose |
|
Secondary |
Concentrations of Capsaicin Inducing 2 or More Coughs (C2) |
The concentrations of capsaicin inducing 2 or more coughs (C2) in participants were assessed in Periods 1 and 2. For capsaicin challenge, doubling concentrations from 0.49 µM to 1000 µM were prepared by dilution of stock solutions with saline, and were administered by inhalation. |
2 hours post-dose |
|
Secondary |
Concentrations of Capsaicin Inducing 5 or More Coughs (C5) |
The concentrations of capsaicin inducing 5 or more coughs (C5) in participants were assessed in Periods 1 and 2. For capsaicin challenge, doubling concentrations from 0.49 µM to 1000 µM were prepared by dilution of stock solutions with saline, and were administered by inhalation. |
2 hours post-dose |
|
Secondary |
Concentrations of ATP Inducing 2 or More Coughs (C2) |
The concentrations of ATP inducing 2 or more coughs (C2) in participants were assessed in Periods 3 and 4. For ATP challenge, doubling concentrations from 0.227 to 929 µmol/mL were prepared from ATP powder, dissolved and diluted in saline, and administered by inhalation. |
2 hours post-dose |
|
Secondary |
Concentrations of ATP Inducing 5 or More Coughs (C5) |
The concentrations of ATP inducing 5 or more coughs (C5) in participants were assessed in Periods 3 and 4. For ATP challenge, doubling concentrations from 0.227 to 929 µmol/mL were prepared from ATP powder, dissolved and diluted in saline, and administered by inhalation. |
2 hours post-dose |
|
Secondary |
Urge-to-Cough in Response to Capsaicin Challenge (Chronic Cough Participants Only) |
In response to capsaicin challenges in Periods 1 and 2, participants with chronic cough completed a visual analogue scale (VAS) at the end of a 4-hour post-dose observation period on Day 1; and at end of 24-hour observation period on Day 2. For both periods, participants were asked to mark on a 100 mm VAS the severity of their urge to cough between 0 mm (no urge-to-cough) and 100 mm (worst urge-to-cough). |
At the end of a 4-hour post-dose observation period on Day 1; at the end of a 24-hour observation period on Day 2 |
|
Secondary |
Urge-to-Cough in Response to ATP Challenge (Chronic Cough Participants Only) |
In response to ATP challenges in Periods 3 and 4, participants with chronic cough completed a VAS at the end of a 4-hour post-dose observation period on Day 1; and at end of 24-hour observation period on Day 2. For both periods, participants were asked to mark on a 100 mm VAS the severity of their urge to cough between 0 mm (no urge-to-cough) and 100 mm (worst urge-to-cough). |
At the end of a 4-hour post-dose observation period on Day 1; at the end of a 24-hour observation period on Day 2 |
|
Secondary |
Cough Severity in Response to Capsaicin Challenge (Chronic Cough Participants Only) |
In response to capsaicin challenges in Periods 1 and 2, participants with chronic cough completed a VAS at the end of a 4-hour post-dose observation period on Day 1; and at end of 24-hour observation period on Day 2. For both periods, participants were asked to mark on a 100 mm VAS their cough severity between 0 mm (no cough) and 100 mm (worst cough). |
At the end of a 4-hour post-dose observation period; at the end of a 24-hour observation period on Day 2 |
|
Secondary |
Cough Severity in Response to ATP Challenge (Chronic Cough Participants Only) |
In response to ATP challenge in Periods 3 and 4, participants with chronic cough completed a VAS at the end of a 4-hour post-dose observation period on Day 1; and at end of 24-hour observation period on Day 2. For both periods, participants were asked to mark on a 100 mm VAS their cough severity between 0 mm (no cough) and 100 mm (worst cough). |
At the end of a 4-hour post-dose observation period on Day 1; at the end of a 24-hour observation period on Day 2 |
|
Secondary |
Daytime Cough Frequency in Participants With Chronic Cough Who Underwent Capsaicin Challenge |
Daily cough frequency monitoring was performed in participants with chronic cough, who were attached to a digital sound recorder with 2 microphones (a lapel air microphone attached to the participant's clothing and an adhesive chest wall microphone attached to the skin at the top of the sternum). Participants wore the sound recorder from the start of capsaicin challenge to bedtime on Day 1 in Periods 1 and 2. The resulting recording was processed by software which cut out the majority of speech and background noise but retained cough sounds. The investigator listened to the recording and documented the number of coughs per hour. |
From start of challenge (2 hours post-dose) to bedtime; up to 12 hours |
|
Secondary |
Daytime Cough Frequency in Participants With Chronic Cough Who Underwent ATP Challenge |
Daily cough frequency monitoring was performed in participants with chronic cough, who were attached to a digital sound recorder with 2 microphones (a lapel air microphone attached to the participant's clothing and an adhesive chest wall microphone attached to the skin at the top of the sternum). Participants wore the sound recorder from the start of ATP challenge to bedtime on Day 1 in Periods 3 and 4. The resulting recording was processed by software which cut out the majority of speech and background noise but retained cough sounds. The investigator listened to the recording and documented the number of coughs per hour. |
From start of challenge (2 hours post-dose) to bedtime; up to 12 hours |
|
Secondary |
Percentage of Participants Who Experienced at Least One Adverse Event |
An adverse event (AE) is any untoward medical occurrence in a study participant administered a pharmaceutical product that does not necessarily have to have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign, symptom, or disease temporally associated with the use of a medicinal product, whether or not related to the medicinal product. |
Up to Day 41 |
|
Secondary |
Percentage of Participants Who Discontinued Study Treatment Due to an Adverse Event |
An adverse event (AE) is any untoward medical occurrence in a study participant administered a pharmaceutical product that does not necessarily have to have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign, symptom, or disease temporally associated with the use of a medicinal product, whether or not related to the medicinal product. |
Up to Day 24 |
|