A Study to Learn How Different Forms of The Study Medicine Called Phenytoin Are Taken up Into the Blood in Healthy Adults

A PHASE 1, OPEN-LABEL, RANDOMIZED, SINGLE-DOSE, 2-WAY CROSSOVER, PIVOTAL BIOEQUIVALENCE STUDY COMPARING 50-MG CHEWABLE DILANTIN® INFATABS® MANUFACTURED AT VEGA BAJA (PUERTO RICO) AND ASCOLI (ITALY) IN HEALTHY ADULT PARTICIPANTS UNDER FASTING CONDITIONS

The purpose of this study is to understand how the different formulation of phenytoin is taken up into the blood in Healthy Adults.

This study is seeking healthy adult participants. All the study participants will receive Phenytoin 50 mg chewable tablets manufactured at Ascoli and Vega Baja manufacturing site.

We will measure how the phenytoin will be taken up into the blood in Healthy Adults following oral dosing of Phenytoin.

This will help us determine if the Phenytoin 50 mg chewable tablets manufactured at Ascoli and Vega Baja manufacturing site are similar or not.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Drug: Phenytoin (Vega Baja); Drug: Phenytoin (Ascoli)

• Study Type: Interventional
• Enrollment (Actual): 35
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Connecticut
    • New Haven, Connecticut, United States, 06511
      • Pfizer Clinical Research Unit - New Haven

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Healthy male participants and female participants of non-childbearing potential aged 18 years or older determined by medical evaluation including detailed medical history, complete physical examination, blood pressure (BP) and pulse rate measurement, 12-lead electrocardiogram (ECG), and/or clinical laboratory tests.
2. Body mass index (BMI) of 16-32 kg/m2; and a total body weight >45 kg (100 lb).

Exclusion Criteria:

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).
2. Female participants of childbearing potential; pregnant female participants; breastfeeding female participants; male participants with partners currently pregnant; male participants able to father children who, with their partner(s) are at risk for pregnancy and are unwilling or unable to use a highly effective method of contraception.
3. History of hypersensitivity to phenytoin or its inactive ingredients.
4. Any medical or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
5. Use of prescription or nonprescription drugs and dietary and herbal supplements within 7 days prior to the first dose of study intervention.
6. Current use of any prohibited concomitant medication(s).
7. History of febrile illness within 5 days prior to first dose.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Phenytoin manufactured at Vega Baja site	Drug: Phenytoin (Vega Baja); Phenytoin 50mg chewable tablets
Experimental: Phenytoin manufactored at Ascoli site	Drug: Phenytoin (Ascoli); Phenytoin 50mg chewable tablets

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast)	72 hours
Maximum Observed Plasma Concentration (Cmax) of Phenytoin	72 hours

Secondary Outcome Measures

Outcome Measure	Time Frame
Number of Participants With Adverse Events (AEs) According to Seriousness	Baseline, up to 35 days post last dose.

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

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

Study record dates

Study Major Dates

• Study Start (Actual): July 3, 2024
• Primary Completion (Actual): October 4, 2024
• Study Completion (Actual): October 4, 2024

Study Registration Dates

• First Submitted: June 14, 2024
• First Submitted That Met QC Criteria: June 14, 2024
• First Posted (Actual): June 20, 2024

Study Record Updates

• Last Update Posted (Actual): October 8, 2024
• Last Update Submitted That Met QC Criteria: October 7, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Keywords: Epilepsy; Bioequivalence; Healthy participants; Pharmacokinetic; Phenytoin
• Additional Relevant MeSH Terms: Molecular Mechanisms of Pharmacological Action; Membrane Transport Modulators; Anticonvulsants; Voltage-Gated Sodium Channel Blockers; Sodium Channel Blockers; Cytochrome P-450 CYP1A2 Inducers; Cytochrome P-450 Enzyme Inducers; Phenytoin
• Other Study ID Numbers: A4121018

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: 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.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No