A Long-term Study of the Safety and Effectiveness of RAP-219 in Adults With Focal Onset Seizures

January 22, 2026 updated by: Rapport Therapeutics Inc.

An Open-label, Long-term Study Evaluating RAP-219 in Adult Participants With Refractory Onset Seizures

This is a clinical research study for an investigational drug called RAP-219 in patients with Refractory Focal Epilepsy. This study is being conducted to determine RAP-219 Long- term safety and open-label antiseizure activity in patients with Refractory Focal Epilepsy.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This is a multi-center, open-label study to evaluate the long-term safety, tolerability, pharmacokinetics, pharmacodynamics and antiseizure activity of RAP-219 in adult participants with refractory focal seizures

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
30

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Idaho
      • Boise, Idaho, United States, 83702
        • Recruiting
        • Consultants in Epilepsy and Neurology, PLLC
    • Minnesota
      • Rochester, Minnesota, United States, 55905
        • Recruiting
        • Mayo Clinic
    • New York
      • New York, New York, United States, 10016
        • Recruiting
        • NYU Langone Comprehensive Epilepsy Center
    • Ohio
      • Cleveland, Ohio, United States, 44195
        • Recruiting
        • Cleveland Clinic Foundation
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • Recruiting
        • University of Pennsylvania - Department of Neurology
    • Tennessee
      • Nashville, Tennessee, United States, 37232
        • Recruiting
        • Vanderbilt University Medical Center
    • Texas
      • Houston, Texas, United States, 770300
        • Recruiting
        • Baylor College of Medicine

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Completion of the associated parent study (RAP-219-FOS-201) treatment period with acceptable tolerability, per Investigator.
  • Diagnosis of refractory focal epilepsy
  • Stable RNS(c) system settings
  • A demonstrated history of compliance with RNS(c) system data interrogation and upload
  • Good overall health other than focal epilepsy, per Investigator.
  • BMI ≥ 18 kg/m^2 and ≤ 45 kg/m^2
  • Willing and able to adhere to all aspects of the protocol.

Exclusion Criteria:

  • Known of hypersensitivity to RAP-219
  • Any clinically unstable or serious medical, neurological (other than epilepsy), psychological, or behavioral problem; laboratory or ECG finding that would increase participant risk or should otherwise exclude the patient from participation, as assessed by Investigator
  • Pregnancy, lactation, or individuals of reproductive potential who do not agree to simultaneously use two effective birth-control methods

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: RAP-219
Drug: RAP-219
Participants will receive one RAP-219 0.125 mg capsule daily for 3 days followed by one 0.25mg tablet RAP-219 daily for 28 days, then one 0.75mg tablet daily for the remainder of the treatment period.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Incidence of treatment-emergent adverse events (TEAEs)
Time Frame: From the start of RAP-219 treatment through 8 weeks after last dose, up to Week 112
From the start of RAP-219 treatment through 8 weeks after last dose, up to Week 112

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Percent change in clinical seizure frequency
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Group median percent change in clinical seizure frequency per 28-day period as reported in a clinical seizure diary
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Clinical seizure 25%, 50%, 75%, and 100% responder proportions
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Proportion of participants with at least 25%, 50%, 75%, or with 100% reduction in clinical seizure frequency per 28-day period as reported in a clinical seizure diary
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Change in clinical seizure-free day frequency
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Group median change in clinical seizure-free day frequency per 28-day period as reported in a clinical seizure diary
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Longest clinical seizure-free interval
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Duration, in days, of the longest continuous period of clinical seizure-free days per period as reported in a clinical seizure diary
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Time to pre-randomization clinical seizure count
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Duration, in days, between the beginning of the open-label treatment period and the nth clinical seizure, where n is the number of clinical seizures per 28-day period during the prospective pre-treatment baseline period, as reported in a clinical seizure diary
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
RNS long episode 30%, 50%, 75% or with 100% responder proportions
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Proportion of participants with at least 30%, 50%, 75%, and 100% reduction in long episodes per 28-day period as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Percent change in RNS long episode frequency
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Group median percent change in long episode frequency per 28-day period as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Change in RNS long episode-free day frequency
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Group median change in long episode-free day frequency per 28-day period as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Longest RNS long episode-free interval
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Duration, in days, of the longest continuous period of long episode-free days per period as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Time to pre-randomization long episode count
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Duration, in days, between the beginning of the open-label treatment period and the mth long episode, where m is the number of long episodes per 28-day period during the pre-treatment baseline period, as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Percent change in RNS estimated electrographic seizure frequency
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Group median percent change in estimated electrographic seizure frequency per 28-day period as recorded by the RNS® System
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Clinical Global Impression of Change (CGI-C) responder count and proportions
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Count and proportion of participants with any improvement (minimally improved, much improved, or very much improved) or clinically meaningful improvement (much improved or very much improved) as reported on the Clinical Global Impression of Change (CGI-C) scale
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Patient Global Impression of Change [PGI-C] responder count and proportions
Time Frame: Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.
Count and proportion of participants with any improvement (minimally improved, much improved, or very much improved) or clinically meaningful improvement (much improved or very much improved) as reported on the Patient Global Impression of Change (PGI-C) scale
Throughout the open-label period until 8 weeks after the last dose, up to Week 112, compared to the pre-treatment baseline period.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Rapport Therapeutics Inc.

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Imran Quraishi, MD, Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
December 15, 2025

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
February 3, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
February 3, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 8, 2025

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 17, 2025

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 21, 2025

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
January 23, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 22, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • RAP-219-FOS-901

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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