Single and Multiple Ascending Doses of NTX-253 in Healthy Participants and Participants With Stable Schizophrenia

NCT07344948 | Recruiting Early Phase 1 FDA Drug

• 1 other identifier: NTX-0253-101
• Study Type: interventional
• Target: 73
• Locations: 1 country
• Sites: 1

Brief Summary

This study will assess the safety, tolerability, and pharmacokinetics of NTX-253 following oral administration in both healthy adult participants as well as adult participants with stable schizophrenia.

Conditions

Schizophrenia Diagnosis; Healthy Participants

Keywords

Phase 1; Healthy volunteer; Schizophrenia; Pharmacokinetics; Single ascending dose; Multiple ascending dose; Food effect; Safety

Outcome Measures

Primary Outcomes (9)

• Number of reported Adverse Events

  Safety and tolerability will be assessed by the incidence and severity of treatment-emergent adverse events.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Number of Adverse Events of Special Interest (AESI)

  Safety and tolerability will be assessed by the incidence and severity of AESIs.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Number of dose limiting treatment emergent adverse events (TEAE)

  Safety and tolerability will be assessed by the incidence and severity of serious or dose limiting TEAEs.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Vital Signs: Change in blood pressure

  Blood pressure measurements

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Vital Signs: Change in temperature

  Oral temperature measurement

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Vital Signs: Change in respiratory rate

  Respiratory rate (number of breaths per minute) measurements

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Vital Signs: Change in heart rate

  Pulse measurements.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Change in physical examination

  Investigator will perform complete physical exam and document any clinically significant conditions.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

• Clinical Laboratory Tests

  Hematology, serum chemistry, urinalysis, and coagulation tests.

  From baseline until Day 8 after a single dose, Day 17 (healthy volunteers) or Day 35 (participants with stable schizophrenia).

Secondary Outcomes (9)

• Maximum observed plasma concentration (Cmax) [Pharmacokinetics]

  From baseline until up to 168 hours after a single dose, or until up to 168 hours after the last dose in the multiple dose cohorts.

• Time of Cmax (tmax) [Pharmacokinetics]

  From baseline until up to 168 hours after a single dose, or until up to 168 hours after the last dose in the multiple dose cohorts.

• Apparent terminal half-life (t1/2)

  From baseline until up to 168 hours after a single dose, or until up to 168 hours after the last dose in the multiple dose cohorts.

• Amount of unchanged drug excreted in urine (Ae) [urinary excretion)

  From baseline until 72 hours after a single dose, or until the last dosing on Day 10 in the multiple dose cohort.

• Percent of dose excreted as unchanged drug in urine (Ae%) [urinary excretion]

  From baseline until 72 hours after a single dose, or until the last dosing on Day 10 in the multiple dose cohort.

Study Arms (5)

NTX-253 Part 1a

EXPERIMENTAL

Participants will be assigned to receive one of multiple single ascending daily oral doses of NTX-253

Drug: NTX-253

Placebo Part 1a

EXPERIMENTAL

Participants will be assigned to receive one of multiple single ascending daily oral doses of placebo

Drug: Placebo

NTX-253 Part 1b

EXPERIMENTAL

Participants will receive the maximum tolerated single oral dose of NTX-253

Drug: NTX-253

NTX-253 Part 2

EXPERIMENTAL

Participants will be assigned to receive one of multiple ascending oral daily doses of NTX-253 for 10 days

Drug: NTX-253

Placebo Part 2

EXPERIMENTAL

Participants will be assigned to receive one of multiple ascending daily oral doses of placebo for 10 days

Drug: Placebo

Interventions

NTX-253 DRUG

Oral Capsule

NTX-253 Part 1a; NTX-253 Part 1b; NTX-253 Part 2

Placebo DRUG

Oral capsule

Placebo Part 1a; Placebo Part 2

Eligibility Criteria

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

You may qualify if:

• Male or non-pregnant, non-lactating female participants, ages 18-55 who are not of childbearing potential, with a truly abstinent lifestyle, or agrees to use medically acceptable forms of birth control
• Part 1 a/b, Part 2 Cohort 7 only: Body mass index (BMI) within the range ≥18.0 to ≤30.0 kg/m2
• Participants in the food effect cohort must be willing to eat a single high fat breakfast
• (Part 2 only): Stable schizophrenia participants (schizophrenia cohorts only)
• Body mass index (BMI) within the range ≥17.5 to ≤36.0 kg/m2
• Positive and Negative Syndrome Scale (PANSS) total score \<80 at screening

You may not qualify if:

• (Part 1a/b, Part 2 Healthy): History of or current clinically significant medical or mental illness
• Cancer diagnosis/treatment in the past 7 years
• Acute or chronic gastrointestinal conditions that would interfere with drug tolerance or absorption
• Any clinically significant, abnormal 12 lead ECG
• Part 2: Any primary DSM-5TR disorder other than schizophrenia
• Participants with schizophrenia who are considered resistant/refractory to antipsychotic treatment by history; history of clozapine use.

Sponsors & Collaborators

• Neurosterix: lead

Study Sites (1)

Collaborative Neuroscience Research, LLC - CenExel

Los Alamitos, California, 90720, United States

RECRUITING

MeSH Terms

Conditions

Schizophrenia

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders

Study Officials

• Doug Feltner, MD

  Neurosterix

  STUDY DIRECTOR

Central Study Contacts

Doug Feltner, Chief Medical Officer, MD

CONTACT

+41 22 884 15 55; doug.feltner@neurosterix.com

Lisa Corey

CONTACT

+41 22 884 15 55; lisa.corey@neurosterix.com

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Crossover design for fasted/fed cohort

Study Record Dates

• First Submitted: November 14, 2025
• First Posted: January 15, 2026
• Study Start: October 3, 2025
• Primary Completion: May 1, 2026
• Study Completion: May 1, 2026
• Last Updated: January 15, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)