Healthy ParticipantsPhase 1NCT05441215
A Study to Learn About the Medicine (PF-07321332 or Nirmatrelvir/Ritonavir) in Healthy Lactating Women
A Phase 1 study testing nirmatrelvir and ritonavir in people with Healthy Participants, run by Pfizer at 1 site in Belgium.
Trial summary
The main purpose of this study is to measure the level of active ingredient of the study medicine (nirmatrelvir) that is secreted in human breast milk when it is given to healthy breastfeeding women. The study medicine consists of two medicines, nirmatrelvir and ritonavir. Read more about this study
- Who is it for?
- Ages 18 to 55 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Healthy Participants
- What is being tested?
- nirmatrelvir and ritonavir
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 8 participants
- Where
- 1 siteBelgium
- Study dates
- 12 Dec 2022to 15 Dec 2023
- Phase
- Phase 1
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- Women only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy lactating females who are actively breast-feeding or expressing breast milk, at least 12 weeks post-partum and not currently pregnant between 18 and 55 years old
- Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb)
- Infants of women enrolled in the study must be able to feed successfully from a bottle or other age-appropriate alternative feeding method prior to the start of the study and must be able to tolerate infant formula if the mother does not have a supply of stored breast milk sufficient to cover the duration of the study
- Participants must be willing to temporarily discontinue breast feeding their infants for a total of 4.5 days (108 hours)
- Participants must be willing to regularly pump breasts throughout the study and express milk according to a schedule designed to maintain lactation throughout the study period
Who cannot join
- Positive test result (RT-PCR) for SARS-CoV-2 infection at the time of screening or Day -1
- Evidence or history of clinically significant findings
- History of febrile illness or mastitis within 5 days prior to the first dose of study medication
- Participants who have received a COVID-19 vaccine within 7 days before screening or admission, or who are to be vaccinated with a COVID-19 vaccine at any time during the study confinement period
- History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, or HCVAb. Hepatitis B vaccination is allowed
- Abnormal vital signs such as blood pressure, 12-lead electrocardiogram
- History of alcohol abuse and/or illicit drug use, tobacco use in excess of 5 cigarettes/day or 2 chews/day
- Blood donation within 60 days
Trial locations and contacts
1 site in 1 country.
Belgium1 site
Pfizer Clinical Research Unit - Brussels
Brussels, Bruxelles-capitale, Région de, B-1070
About this study
Official title: A PHASE I, MULTIPLE DOSE, OPEN-LABEL PHARMACOKINETIC STUDY OF NIRMATRELVIR/RITONAVIR IN HEALTHY LACTATING WOMEN
The main purpose of this study is to measure the level of active ingredient of the study medicine (nirmatrelvir) that is secreted in human breast milk when it is given to healthy breastfeeding women. The study medicine consists of two medicines, nirmatrelvir and ritonavir. We are seeking female participants who are:
- Actively breast-feeding (lactating) at least 12 weeks postpartum;
- Age between 18 to 55 years and not currently pregnant;
- Have a Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb).
Participants will take the study medicine by mouth for a total of 3 times over 2 days (2 morning doses and 1 evening dose) at the study clinic. We will periodically collect breast milk from day 2 to 4 to measure the level of nirmatrelvir and ritonavir in it. A safety follow up call will be conducted around 28-35 days from the last dose to monitor any reactions participants may have to the study medicine.
- Conditions
- Healthy Participants
- Being tested
- nirmatrelvir, ritonavir
- Keywords
- Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), Lactation, COVID-19, Breastfeeding, Protease Inhibitor
- Medical subject headings
- Breast Feeding, COVID-19
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
nirmatrelvirDrug
Also called PF-07321332/ritonavir
nirmatrelvir/ritonavir
ritonavirDrug
Also called PF-07321332/ritonavir
nirmatrelvir/ritonavir
| Study group | Role | What they receive |
|---|---|---|
| nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir will be given by mouth two times a day as a tablet Receives: Drug: nirmatrelvir; Drug: ritonavir |
What is being measured
The primary outcome is the main question the study is designed to answer.
The Maximum Observed Concentration of Nirmatrelvir in Breast Milk Over the Dosing Interval
The maximum observed concentration and was directly observed from data.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Time to Reach Cmax of Nirmatrelvir in Breast Milk
Cmax was defined as maximum observed concentration of nirmatrelvir in breast milk.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Area Under the Concentration-Time Profile From Time Zero to End of Dosing Interval for Nirmatrelvir in Breast Milk
Area under the concentration curve for nirmatrelvir in breast milk from time 0 to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Terminal Half-Life of Nirmatrelvir in Breast Milk
The time measured for the breast milk nirmatrelvir concentration to decrease by one half.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Average Steady State Concentration of Nirmatrelvir in Breast Milk
The average concentration across time and can be calculated by dividing AUCtau by time. AUCtau was defined area under the concentration curve from time 0 to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Amount of Nirmatrelvir Excreted in Breast Milk Over the Dosing Interval Tau
The amount of nirmatrelvir excreted into breast milk over the dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Percent of Amount of Nirmatrelvir Excreted in Breast Milk Over The Dosing Interval Tau
The percent of nirmatelvir excreted in breast milk to amount of breast milk over the dosing interval .
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Breast Milk Clearance of Nirmatrelvir
Clearance was defined as the apparent volume (Liter) of breast milk completely cleared the nirmatrelvir per hour.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Secondary outcomes (41)
The Maximum Observed Concentration of Ritonavir in Breast Milk Observed Over the Dosing Interval
The maximum observed concentration and was directly observed from data.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Time to Reach Cmax of Ritonavir in Breast Milk
Cmax was defined as maximum observed concentration of ritonavir in breast milk.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Area Under the Concentration-Time Profile for Ritonavir in Breast Milk From Time Zero to End of Dosing Interval
Area under the concentration curve for ritonavir in breast milk from time 0 to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Half-Life of Ritonavir in Breast Milk
The time measured for the breast milk ritonavir concentration to decrease by one half.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Average Steady State Concentration of Ritonavir in Breast Milk
The average concentration across time and can be calculated by dividing AUCtau by time. AUCtau was defined area under the concentration curve from time 0 to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Amount of Ritonavir Excreted in Breast Milk Over the Dosing Interval Tau
The amount of ritonavir excreted into breast milk over the dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Percent of Ritonavir Excreted in Breast Milk Over The Dosing Interval Tau
The percent of ritonavir excreted in breast milk to amount of breast milk over the dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Breast Milk Clearance of Ritonavir
Clearance was defined as the apparent volume (L) of breast milk completely cleared the ritonavir per hour.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Maximum Observed Concentration of Nirmatrelvir in Plasma Observed Over the Dosing Interval
The maximum observed concentration and was directly observed from data.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Maximum Observed Concentration of Ritonavir in Plasma Observed Over the Dosing Interval
The maximum observed concentration and was directly observed from data.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Area Under the Concentration-Time Profile for Nirmatrelvir in Plasma From Time Zero to End of Dosing Interval
Area under the concentration curve for nirmatrelvir in breast milk from time 0 to end of dosing interval.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Area Under the Concentration-Time Profile for Ritonavir in Plasma From Time Zero to End of Dosing Interval
Area under the concentration curve for ritonavir in plasma from time 0 to end of dosing interval.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Half-Life of Nirmatrelvir in Plasma
The time measured for the plasma nirmatrelvir concentration to decrease by one half.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Half-Life of Ritonavir in Plasma
The time measured for the plasma ritonavir concentration to decrease by one half.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Minimum Plasma Concentration of Nirmatrelvir Observed Over the Dosing Interval
The minimum observed concentration and was directly observed from data.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Minimum Plasma Concentration of Ritonavir Observed Over the Dosing Interval
The minimum observed concentration and was directly observed from data.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Time to Reach Cmax of Nirmatrelvir in Plasma
Cmax was defined as maximum observed concentration of nirmatrelvir in plasma.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Time to Reach Cmax of Ritonavir in Plasma
Cmax was defined as maximum observed concentration of ritonavir in plasma.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Clearance of Nirmatrelvir From Plasma
Clearance was defined as the apparent volume (L) of plasma completely cleared the nirmatrelvir per hour.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Clearance of Ritonavir From Plasma
Clearance was defined as the apparent volume (L) of plasma completely cleared the ritonavir per hour.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Volume of Nirmatrelvir Distribution
Volume of distribution was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug. Apparent volume of distribution after oral dose was influenced by the fraction absorbed.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Volume of Ritonavir Distribution
Volume of distribution was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug. Apparent volume of distribution after oral dose was influenced by the fraction absorbed.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Average Steady State Concentration of Nirmatrelvir in Plasma
The average concentration across time and can be calculated by dividing AUCtau by time. AUCtau was defined area under the concentration curve from time 0 to end of dosing interval.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Average Steady State Concentration of Ritonavir in Plasma
The average concentration across time and can be calculated by dividing AUCtau by time. AUCtau was defined area under the concentration curve from time 0 to end of dosing interval.
Measured: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Daily (24 Hour) Amount of Nirmatrelvir Excreted in Breast Milk
Amount of nirmatrelvir excreted in breast milk in 24 hours.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Daily (24 Hour) Amount of Ritonavir Excreted in Breast Milk
Amount of ritonavir excreted in breast milk in 24 hours.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Nirmatrelvir for AUCtau During Dosing Interval
The ratio of area under the concentration-time profile for nirmatrelvir in milk to those in plasma from time zero to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Ritonavir for AUCtau During Dosing Interval
The ratio of area under the concentration-time profile for ritonavir in milk to those in plasma from time zero to end of dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Nirmatrelvir for Cmax During Dosing Interval
The ratio of the maximum concentration of nirmatrelvir in breast milk to those in plasma observed over the dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Ritonavir for Cmax During Dosing Interval
The ratio of the maximum concentration of ritonavir in breast milk to those in plasma observed over the dosing interval.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Body Weight Normalized Infant Dose (BWNID) of Nirmatrelvir in mg/kg/Day
BWNID = MPAUCtau * Cav * 150 mL/kg/day, where 150 mL/kg/day^2 is the standardized milk consumption for an infant. MPAUCtau: Milk to plasma ratio for AUCtau. Cav: Average concentration.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNID of Ritonavir in mg/kg/Day
BWNID = MPAUCtau * Cav * 150 mL/kg/day, where 150 mL/kg/day^2 is the standardized milk consumption for an infant. MPAUCtau: Milk to plasma ratio for AUCtau. Cav: Average concentration.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Body Weight Normalized Maternal Dose (BWNMD) of Nirmatrelvir in mg/kg/Day
Maternal dose in mg/day (300 mg BID = 600 mg/day for nirmatrelvir and 100 mg BID = 200 mg/day for ritonavir) / maternal weight in kg at screening.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNMD of Ritonavir in mg/kg/Day
Maternal dose in mg/day (300 mg BID = 600 mg/day for nirmatrelvir and 100 mg BID = 200 mg/day for ritonavir) / maternal weight in kg at screening.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Infant Dose Expressed As % of Body Weight Normalized Maternal Dose (BWNIDPCM) for Nirmatrelvir
BWNIDPCM = 100 * BWNID / BWNMD.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNIDPCM for Ritonavir
BWNIDPCM = 100 * BWNID / BWNMD.
Measured: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Number of Participants With Treatment Emergent Adverse Events
An adverse event (AE) was 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. AEs might arise from symptoms or other complaints reported to the investigator by the participant (or, when appropriate, by a caregiver, surrogate, or the participant's legally authorized representative), or they might arise from clinical findings of the investigator or other healthcare providers (clinical signs, test results, etc.). TEAEs were those with initial onset or increasing in severity after the first dose of study treatment.
Measured: From the first dose of study treatment on Day 1 to up to 28 days after the last dose of study intervention on Day 2 (maximum to 30 days)
Number of Participants With Laboratory Abnormalities (Without Regard to Baseline Abnormality)
The laboratory abnormality parameters included urinalysis: urine bilirubin (>=1), urine hemoglobin (>=1) and leukocyte esterase (>=1).
Measured: At Screening (Day -28 to Day -2), Day -1, and Day 4
Number of Participants With Vital Signs Abnormalities
Single supine blood pressure (BP), and pulse rate (PR) were performed following approximately a 5-minute rest in a supine position. BP, and PR assessments will be performed after collection of electrocardiogram (ECGs) and prior to collection of blood draws if scheduled at the same time. Vital signs abnormality included supine systolic BP <90mmHg.
Measured: At Screening (Day -28 to Day -2), Pre-dose and 12 Hours post-dose on Day 1, Pre-dose and 48 Hours Post-dose on Day 2
Number of Participants With ECG Abnormalities
Standard 12-lead ECGs utilizing limb leads (with a 10 second rhythm strip) were collected. All ECG assessments were made after at least a 5-minute rest in a supine position and prior to any blood draws or vital sign measurements.
Measured: At Screening (from Day -28 to Day -2)
Number of Participants With Physical Examination Abnormalities
Physical examination included height, weight and body mass index (BMI, BMI = weight [kg] / height [m^2]) obtained for eligibility criteria. Physical examination abnormalities: BMI <17.5 kg/m^2; and a total body weight <=50 kg (110 lb).
Measured: At Screening (from Day -28 to Day -2) or Day -1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jul 2022
- Study start12 Dec 2022
- Primary completion15 Dec 2023
- Study completion15 Dec 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Healthy ParticipantsStudies of the same condition, open and under way.
- More trials run by PfizerThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 8 participants (actual)
Sponsor and investigators
- Lead sponsor
- Pfizer
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Pfizer CT.gov Call Center, Study director, Pfizer
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05441215
- Sponsor's protocol ID
- C4671039
- Other IDs
- 2022-001020-15
- Status last verified
- Apr 2026
- First submitted
- 28 Jun 2022
- Last updated
- 1 May 2026
- Results posted
- Yes, on ClinicalTrials.gov
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.
Publications
Gerhart J, Cheruvu N, Pelletier K, Matschke K, Shi H, Mfopou JK, Hammond J, Singh RSP. A Phase 1 Multiple-Dose, Open-Label, Pharmacokinetic Study of Nirmatrelvir/Ritonavir in Healthy Lactating Women. Clin Transl Sci. 2026 May;19(5):e70552. doi: 10.1111/cts.70552.
PubMed 42012328
Study at a glance
From the registry record, last updated by the sponsor on 1 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A PHASE I, MULTIPLE DOSE, OPEN-LABEL PHARMACOKINETIC STUDY OF NIRMATRELVIR/RITONAVIR IN HEALTHY LACTATING WOMEN
- ClinicalTrials.gov ID
- NCT05441215
- Acronym / sponsor ID
- C4671039
- Conditions
- Healthy Participants
- Keywords
- Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), Lactation, COVID-19, Breastfeeding, Protease Inhibitor
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 8 participants (actual)
- Lead sponsor
- PfizerIndustry (pharma, biotech, devices)
- Study start
- 12 Dec 2022 (actual)
- Primary completion
- 15 Dec 2023 (actual)
- Study completion
- 15 Dec 2023 (actual)
- First posted
- 1 Jul 2022 (actual)
- Results
- Posted 1 May 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The main purpose of this study is to measure the level of active ingredient of the study medicine (nirmatrelvir) that is secreted in human breast milk when it is given to healthy breastfeeding women. The study medicine consists of two medicines, nirmatrelvir and ritonavir. We are seeking female participants who are:
- Actively breast-feeding (lactating) at least 12 weeks postpartum;
- Age between 18 to 55 years and not currently pregnant;
- Have a Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb).
Participants will take the study medicine by mouth for a total of 3 times over 2 days (2 morning doses and 1 evening dose) at the study clinic. We will periodically collect breast milk from day 2 to 4 to measure the level of nirmatrelvir and ritonavir in it. A safety follow up call will be conducted around 28-35 days from the last dose to monitor any reactions participants may have to the study medicine.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir will be given by mouth two times a day as a tablet |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Healthy lactating females who are actively breast-feeding or expressing breast milk, at least 12 weeks post-partum and not currently pregnant between 18 and 55 years old
- Body Mass Index (BMI): 17.5 kg/m2; and a total body weight >50 kg (110 lb)
- Infants of women enrolled in the study must be able to feed successfully from a bottle or other age-appropriate alternative feeding method prior to the start of the study and must be able to tolerate infant formula if the mother does not have a supply of stored breast milk sufficient to cover the duration of the study
- Participants must be willing to temporarily discontinue breast feeding their infants for a total of 4.5 days (108 hours)
- Participants must be willing to regularly pump breasts throughout the study and express milk according to a schedule designed to maintain lactation throughout the study period
Key exclusion criteria (8 listed)
- Positive test result (RT-PCR) for SARS-CoV-2 infection at the time of screening or Day -1
- Evidence or history of clinically significant findings
- History of febrile illness or mastitis within 5 days prior to the first dose of study medication
- Participants who have received a COVID-19 vaccine within 7 days before screening or admission, or who are to be vaccinated with a COVID-19 vaccine at any time during the study confinement period
- History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, or HCVAb. Hepatitis B vaccination is allowed
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| nirmatrelvirAlso: PF-07321332/ritonavirnirmatrelvir/ritonavir | Drug | nirmatrelvir/ritonavir |
| ritonavirAlso: PF-07321332/ritonavirnirmatrelvir/ritonavir | Drug | nirmatrelvir/ritonavir |
Primary outcome
The Maximum Observed Concentration of Nirmatrelvir in Breast Milk Over the Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The maximum observed concentration and was directly observed from data.
Time to Reach Cmax of Nirmatrelvir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Cmax was defined as maximum observed concentration of nirmatrelvir in breast milk.
Area Under the Concentration-Time Profile From Time Zero to End of Dosing Interval for Nirmatrelvir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Area under the concentration curve for nirmatrelvir in breast milk from time 0 to end of dosing interval.
Terminal Half-Life of Nirmatrelvir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The time measured for the breast milk nirmatrelvir concentration to decrease by one half.
The Average Steady State Concentration of Nirmatrelvir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The average concentration across time and can be calculated by dividing AUCtau by time. AUCtau was defined area under the concentration curve from time 0 to end of dosing interval.
The Amount of Nirmatrelvir Excreted in Breast Milk Over the Dosing Interval Tau
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The amount of nirmatrelvir excreted into breast milk over the dosing interval.
The Percent of Amount of Nirmatrelvir Excreted in Breast Milk Over The Dosing Interval Tau
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The percent of nirmatelvir excreted in breast milk to amount of breast milk over the dosing interval .
Breast Milk Clearance of Nirmatrelvir
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Clearance was defined as the apparent volume (Liter) of breast milk completely cleared the nirmatrelvir per hour.
41 secondary outcomes
The Maximum Observed Concentration of Ritonavir in Breast Milk Observed Over the Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Time to Reach Cmax of Ritonavir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Area Under the Concentration-Time Profile for Ritonavir in Breast Milk From Time Zero to End of Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Half-Life of Ritonavir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Average Steady State Concentration of Ritonavir in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Amount of Ritonavir Excreted in Breast Milk Over the Dosing Interval Tau
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Percent of Ritonavir Excreted in Breast Milk Over The Dosing Interval Tau
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Breast Milk Clearance of Ritonavir
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
The Maximum Observed Concentration of Nirmatrelvir in Plasma Observed Over the Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Maximum Observed Concentration of Ritonavir in Plasma Observed Over the Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Area Under the Concentration-Time Profile for Nirmatrelvir in Plasma From Time Zero to End of Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Area Under the Concentration-Time Profile for Ritonavir in Plasma From Time Zero to End of Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Half-Life of Nirmatrelvir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Half-Life of Ritonavir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Minimum Plasma Concentration of Nirmatrelvir Observed Over the Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Minimum Plasma Concentration of Ritonavir Observed Over the Dosing Interval
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Time to Reach Cmax of Nirmatrelvir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Time to Reach Cmax of Ritonavir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Clearance of Nirmatrelvir From Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Clearance of Ritonavir From Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Volume of Nirmatrelvir Distribution
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Apparent Volume of Ritonavir Distribution
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Average Steady State Concentration of Nirmatrelvir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
The Average Steady State Concentration of Ritonavir in Plasma
Time frame: At 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 18, 24, 32, 40, 48 Hours Post Dose on Day 2
Daily (24 Hour) Amount of Nirmatrelvir Excreted in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Daily (24 Hour) Amount of Ritonavir Excreted in Breast Milk
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Nirmatrelvir for AUCtau During Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Ritonavir for AUCtau During Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Nirmatrelvir for Cmax During Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Milk to Plasma Ratio of Ritonavir for Cmax During Dosing Interval
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Body Weight Normalized Infant Dose (BWNID) of Nirmatrelvir in mg/kg/Day
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNID of Ritonavir in mg/kg/Day
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Body Weight Normalized Maternal Dose (BWNMD) of Nirmatrelvir in mg/kg/Day
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNMD of Ritonavir in mg/kg/Day
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Infant Dose Expressed As % of Body Weight Normalized Maternal Dose (BWNIDPCM) for Nirmatrelvir
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
BWNIDPCM for Ritonavir
Time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2
Number of Participants With Treatment Emergent Adverse Events
Time frame: From the first dose of study treatment on Day 1 to up to 28 days after the last dose of study intervention on Day 2 (maximum to 30 days)
Number of Participants With Laboratory Abnormalities (Without Regard to Baseline Abnormality)
Time frame: At Screening (Day -28 to Day -2), Day -1, and Day 4
Number of Participants With Vital Signs Abnormalities
Time frame: At Screening (Day -28 to Day -2), Pre-dose and 12 Hours post-dose on Day 1, Pre-dose and 48 Hours Post-dose on Day 2
Number of Participants With ECG Abnormalities
Time frame: At Screening (from Day -28 to Day -2)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 1 May 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 42012328Gerhart J, Cheruvu N, Pelletier K, Matschke K, Shi H, Mfopou JK, Hammond J, Singh RSP. A Phase 1 Multiple-Dose, Open-Label, Pharmacokinetic Study of Nirmatrelvir/Ritonavir in Healthy Lactating Women. Clin Transl Sci. 2026 May;19(5):e70552. doi: 10.1111/cts.70552.
- To obtain contact information for a study center near you, click here.Link provided by the sponsor.
- Individual participant dataSharing planned: No. Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Pfizer CT.gov Call Center study director
Pfizer
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing nirmatrelvir and ritonavir in people with Healthy Participants, run by Pfizer at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 1 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 1 May 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The Maximum Observed Concentration of Nirmatrelvir in Breast Milk Over the Dosing Interval (time frame: At Day -1 (24 Hours Prior to Dosing on Day 1), Pre-dose on Day 1, 0 to 2, 2 to 4, 4 to 8, 8 to 12, 12 to 24, 24 to 32, 32 to 40 and 40 to 48 Hours Post-dose on Day 2). The study lists 8 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05441215, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 1 May 2026.