WithdrawnNCT05178654Updated Jan 31, 2022

Study to Investigate the Mass Balance, Metabolism, and Excretion of [14C]PF-07321332 in Healthy Male Participants.

A Phase 1 interventional study of [14C]PF-07321332 in Healthy Participants, sponsored by Pfizer. Withdrawn. Open to male participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-01-31.

Sponsored by Pfizer · Phase 1, Interventional, and Basic science

Why this study was withdrawn

Based on various healthy authorities feedback on PAXLOVID submission, this study is no longer required.

Phase: Phase 1
Study type: Interventional
Enrollment: 0
Allocation: Randomized
Ages: 18 Years and older
Sex: Male

Study summary

This study is to characterize mass balance and further the understanding of human pharmacokinetics, metabolism, and excretion of radiolabeled [14C]PF-07321332 in healthy male participants following oral administration with ritonavir.

Conditions studied

Healthy Participants

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COVID-19 7,774

Keywords

Mass balance
metabolism and execration
COVID-19 (Coronavirus disease 2019)
SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2)

In context

COVID-19

7,774 studies on the registry are indexed under COVID-19; 482 are open to participants now.

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Lead sponsor

Pfizer is the lead sponsor of 3,323 studies on the registry; 145 are open to participants now.

Of its 597 completed or terminated interventional studies of FDA-regulated products, 391 (65%) have results posted.

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Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: Male
Accepts healthy volunteers: Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination (PE), laboratory tests, vital signs and standard 12 lead ECGs.
Body mass index (BMI) of 17.5 to 30.5 kg/m2; and a total body weight >50 kg (110 lb).
Participants who are willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations, and other study procedures

Exclusion criteria

Exclusion Criteria:

Positive test result for SARS-CoV-2 infection at the time of Screening or Day -1.
Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
Clinically relevant abnormalities requiring treatment (eg, acute myocardial infarction, unstable ischemic conditions, evidence of ventricular dysfunction, serious tachy or brady arrhythmias) or indicating serious underlying heart disease (eg, prolonged PR interval, cardiomyopathy, heart failure greater than New York Heart Association (NYHA) 1, underlying structural heart disease, Wolff Parkinson-White syndrome).
Any condition possibly affecting drug absorption (eg, gastrectomy, cholecystectomy).
History of human immunodeficiency virus (HIV) infection, hepatitis B, or hepatitis C; positive testing for HIV, hepatitis B surface antigen (HBsAg), or hepatitis B surface antibody (HCVAb). Hepatitis B vaccination is allowed.
Use of prescription or nonprescription drugs and dietary and herbal supplements within 7 days or 5 half lives (whichever is longer) prior to the first dose of study intervention.
Participant 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.
A positive urine drug test.
Participants enrolled in a previous radio-nucleotide study or who have received radiotherapy within 12 months prior to screening or such that total radioactivity would exceed acceptable dosimetry (ie, occupational exposure of 5 rems per year).

Study design

Phase: Phase 1
Primary purpose: Basic science
Allocation: Randomized
Intervention model: Single group
Masking: None (open label)
Enrollment: 0 participants (actual)

Study arms

Experimental
[14C]PF-07321332
Single oral dose of 300 mg \[14C\]PF-07321332 containing approximately 100 µCi \[14C\]PF-07321332 coadministered with 100 mg ritonavir.
Drug: [14C]PF-07321332

Interventions

Drug[14C]PF-07321332
Single oral dose of 300 mg \[14C\]PF-07321332 containing approximately 100 µCi \[14C\]PF-07321332 coadministered with 100 mg ritonavir.

What researchers measure

Primary outcomes

Cumulative amount of radioactivity Recovered in Urine (Ae)
Ae is the cumulative amount of radioactivity recovered in urine. Cumulative amount was calculated as sum of urine drug concentration in sample volume for each collection interval. Sample volume = (urine weight in gram \[g\]/1.020), where 1.020 g/mL is the approximate specific gravity of urine.
Time frame: 0 to 240 hours
Cumulative amount of radioactivity Recovered in Feces (Ae)
Fe is the cumulative amount of radioactivity recovered in feces. Cumulative amount was calculated as sum of feces drug concentration in sample volume for each collection interval. Sample volume = (feces weight in gram \[g\]).
Time frame: 0 to 240 hours
Metabolic Profiling in blood
Metabolic profiling/identification and determination of relative abundance of \[14C\]PF-07321332 and the metabolites of \[14C\]PF-07321332 in plasma if possible.
Time frame: 0 to 24 hours
Metabolic Profiling in Urine
Metabolic profiling/identification and determination of relative abundance of \[14C\]PF-07321332 and the metabolites of \[14C\]PF-07321332 in urine if possible.
Time frame: 0 to 240 hours
Metabolic Profiling in Feces
Metabolic profiling/identification and determination of relative abundance of \[14C\]PF-07321332 and the metabolites of \[14C\]PF-07321332 in feces if possible.
Time frame: 0 to 240 hours

Secondary outcomes

Number of Participants With Treatment Emergent Treatment-Related Adverse Events (AEs)
Time frame: Baseline (Day 0) up to 28 days after last dose of study medication
Number of Participants With Notable Electrocardiogram (ECG) Values
Time frame: From baseline up to 11 days.
Number of Participants With Clinically Notable Vital Signs
Time frame: From baseline up to 11 days
Number of Participants With Clinically Notable Clinical Chemistry/Biochemistry Shifts Based on National Cancer Institute Common Terminology Criteria (NCI-CTCAE) Grade
Time frame: From baseline up to 11 days

Study locations

No study locations are listed for this record.

References and documents

Individual participant data

Plan to share: 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.

Timeline

Tracking since Sep 25, 2026

ElapsedEstimatedEstimated, not yet reached

Start is estimated for Feb 2022; primary completion for Apr 2022, 1 month later.

How these figures are worked out, and which studies are left out of them.

Registered: Dec 16, 2021
First posted: Jan 5, 2022
StartEst.: Feb 22, 2022
Primary completionEst.: Apr 1, 2022
CompletionEst.: Apr 1, 2022
Last update: Jan 31, 2022

What these dates mean

Start.: When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.: When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.: When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.: Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.

No changes since tracking began. The registry record was last updated on Jan 31, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT05178654
Lead sponsor: Pfizer
Responsible party: Sponsor
First posted: Jan 5, 2022
Start date: Feb 22, 2022 (estimated)
Primary completion: Apr 1, 2022 (estimated)
Completion: Apr 1, 2022 (estimated)
Last update: Jan 31, 2022

Study contacts

Pfizer CT.gov Call Center

study director · Pfizer

Oversight

Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is withdrawn, as verified in Jan 2022. You cannot join it, but the record below documents what was studied.

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Discussion

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