Study to Investigate the Mass Balance, Metabolism, and Excretion of [14C]-PF-07304814 in Healthy Participants

NCT05050682 | Completed Phase 1 Results FDA Drug

• 2 other identifiers: C4611003NCT05050682
• Study Type: interventional
• Target: 5
• Locations: 1 country
• Sites: 1

Brief Summary

This open-label, single dose study in approximately 5 healthy male and female (of non childbearing potential only) participants has been designed to characterize mass balance and further the understanding of human pharmacokinetics, metabolism, and excretion of PF 07304814 administered at a dose of 500 mg \[14C\] PF-07304814 containing approximately 420 nCi \[14C\] PF-07304814 as a constant-rate, continuous IV infusion over 24 hours

Conditions

Healthy

Keywords

COVID-19; SARS-COV-2; Viral Disease

Outcome Measures

Primary Outcomes (17)

• The Mean (SD) Amount of [14C] Recovered in Urine, as a Percent of the Total [14C] Dose Administered

  This is to confirm mass balance and characterize the routes of elimination of \[14C\]-PF-07304814 and drug related materials following 420 nCi/500 mg dose of \[14C\] PF-07304814.

  from pre-dose to 216h post the start of infusion

• The Mean (SD) Amount of [14C] Recovered in Feces, as a Percent of the Total [14C] Dose Administered

  This is to confirm mass balance and characterize the routes of elimination of \[14C\]-PF-07304814 and drug related materials following 420 nCi/500 mg dose of \[14C\] PF-07304814.

  from pre-dose to 216h post the start of infusion

• The Mean (SD) Percentage of [14C] Relative to the Administered Dose in Excreta (Urine + Feces)

  This is to confirm mass balance and characterize the routes of elimination of \[14C\]-PF-07304814 and drug related materials following 420 nCi/500 mg dose of \[14C\] PF-07304814.

  from pre-dose to 216h post the start of infusion

• Area Under the Concentration-time Profile From Time Zero to the Time of the Last Quantifiable Concentration (AUClast) for Plasma PF-07304814 and Plasma PF-00835231

  Area under the concentration-time profile from time zero to the time of the last quantifiable concentration (Clast), using linear/log trapezoidal method.

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Area Under the Concentration-time Profile From Time Zero to the Time of the Last Quantifiable Concentration (AUClast) for Plasma Total [14C]

  Area under the concentration-time profile from time zero to the time of the last quantifiable concentration (Clast), using linear/log trapezoidal method.

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Area Under the Concentration-time Profile From Time Zero Extrapolated to Infinite Time (AUCinf) for Plasma PF-00835231

  Area under the concentration-time profile from time zero extrapolated to infinite time. AUClast + (Clast\*/kel), where Clast\* is the predicted plasma concentration at the last quantifiable time point estimated from the log-linear regression analysis (if data permit).

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• AUCinf for Plasma Total [14C]

  Area under the concentration-time profile from time zero extrapolated to infinite time. AUClast + (Clast\*/kel), where Clast\* is the predicted plasma concentration at the last quantifiable time point estimated from the log-linear regression analysis (if data permit).

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Maximum Observed Plasma Concentration (Cmax) for Plasma PF-07304814 and Plasma PF-00835231

  Maximum observed plasma concentration. This was observed directly from data.

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Cmax for Plasma Total [14C]

  Maximum observed plasma concentration. This was observed directly from data.

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Time for Cmax (Tmax) for Plasma PF-07304814 and Plasma PF-00835231

  Time for Cmax. This was observed directly from data as time of first occurrence.

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Tmax for Plasma Total 14C

  Time for Cmax. This was observed directly from data as time of first occurrence.

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Obsereved Plasma Concentration at 24 Hours (C24) for Plasma PF-07304814 and Plasma PF-00835231

  Obsereved plasma concentration at 24 hours. This was observed directly from data.

  24 hours post the start of infusion

• C24 for Plasma Total [14C]

  Obsereved plasma concentration at 24 hours. This was observed directly from data.

  24hours post the start of infusion

• Systematic Clearance (CL) for Plasma PF-07304814

  Systemic clearance. This was determined by Dose/AUCinf (if data permit).

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Steady-state Volume of Distribution Following Intravenous Infusion (Vss) for Plasma PF-07304814

  Steady-state volume of distribution following intravenous infusion. This was determined by Vss=CL × \[MRT-(infusion time/2)\] where MRT is the Mean Residence Time and is calculated as AUMCinf (the area under the first moment curve from time 0 extrapolated to infinite time)/AUCinf (area under the concentration-time profile from time 0 extrapolated to infinite time), if data permit.

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• Terminal Elimination Half-life (t½) for Plasma PF-00835231

  Terminal elimination half-life. This was determined by Loge(2)/kel, where kel is the terminal phase rate constant calculated by a linear regression of the log-linear concentration-time curve (if data permit).

  0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

• t½ for Plasma Total [14C]

  Terminal elimination half-life. This was determined by Loge(2)/kel, where kel is the terminal phase rate constant calculated by a linear regression of the log-linear concentration-time curve (if data permit).

  pre-dose, 0.5h, 1h, 2h, 6h, 12h, 24h, 25h, 27h, 32h, 48h, 72h, 96h, 120h, 144h, 216h post the start of infusion

Secondary Outcomes (5)

• Percentage of Total Radioactivity in Each Matrix (Plasma, Urine and Feces) of Metabolites of PF-07304814

  Predose to maximum of Day 10

• Number of Subjects With Treatment-emergent Adverse Events (TEAEs)

  From first dose up to 28-35 days from administration of the dose of study intervention (maximum of 35 days)

• Number of Subjects With Vital Signs Data Meeting Categorical Summarization Criteria

  from Screening (Day-42 to Day-2) to 216h or early termination/discontinuation

• Number of Subjects With Laboratory Test Abnormalities (Without Regards to Baseline Abnormality)

  From Screening (Day-42 to Day-2) to 216h or early termination/discontinuation

• Number of Subjects With Electrocardiogram (ECG) Data Meeting Categorical Summarization Criteria

  From Screening (Day-42 to Day-2) to 216h or early termination/discontinuation

Study Arms (1)

PF-07304814

EXPERIMENTAL

PF-07304814 is an anti-viral, formulated for intravenous delivery

Drug: PF-07304814

Interventions

PF-07304814 DRUG

PF-07304814 is an anti-viral, formulated for intravenous delivery

PF-07304814

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male and female participants must be 18 to 55 years of age, inclusive, at the time of signing the ICD.
• Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and ECGs.
• Participants who are willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations, and other study procedures.
• BMI of 18 to 32 kg/m2; and a total body weight \>50 kg (110 lb).

You may not qualify if:

• 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).
• Positive test result for SARS-CoV-2 infection at the time of Screening or Day -1.
• 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.
• Previous administration with an investigational drug within 30 days (or as determined by the local requirement) or 5 half lives preceding the first dose of study intervention used in this study (whichever is longer).
• Participants who have received a COVID-19 vaccine within the past 2 weeks; and/or participants who are scheduled to receive a second COVID-19 vaccination dose during the in-clinical period of this study.
• A positive urine drug test.
• Total 14C radioactivity measured in plasma exceeding 11 mBq/mL at "Screening" .
• Females who are breastfeeding.
• History of tobacco or nicotine use within 3 months prior to dosing, or a positive cotinine at screening or Day -1.
• Participants enrolled in a previous radionucleotide 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 rem per year).
• \. Participants whose occupation requires exposure to radiation or monitoring of radiation exposure.
• \. Investigator site staff or Pfizer employees directly involved in the conduct of the study, site staff otherwise supervised by the investigator, and their respective family members.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Fortrea Clinical Research Unit - Madison

Madison, Wisconsin, 53704, United States

Location

Related Links

• To obtain contact information for a study center near you, click here.

MeSH Terms

Conditions

COVID-19; Virus Diseases

Interventions

lufotrelvir

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases

Results Point of Contact

• Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer Inc.

ClinicalTrials.gov_Inquiries@pfizer.com

1-800-718-1021

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 10, 2021
• First Posted: September 20, 2021
• Study Start: October 7, 2021
• Primary Completion: December 10, 2021
• Study Completion: December 10, 2021
• Last Updated: October 20, 2025
• Results First Posted: September 23, 2025

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)