A Safety and Immunogenicity Trial of OCU500, ChAd36 Vector Encoding SARS-CoV-2 Spike Vaccine Via Intranasal and Inhalational Routes in Previously Vaccinated Adults

NCT07536308 | Recruiting Phase 1 FDA Drug

• 1 other identifier: 24-1102
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 5

Brief Summary

This phase 1 randomized, open-label, dose-escalation clinical trial evaluates the safety and immunogenicity of OCU500, a ChAd36 Vector Encoding SARS-CoV-2 Spike Vaccine, in healthy adults aged 18-64 who previously completed a primary COVID-19 vaccination series and at least one booster. The study evaluates two dose levels (1×10\^10 viral particles (VP) and 5×10\^10 VP) and two routes of administration (intranasal and inhaled). The trial includes 80 participants across four study arms (20 per arm). The primary objective is to evaluate the safety and reactogenicity of a single dose of OCU500 administered in previously vaccinated healthy adults.

Conditions

COVID-19

Keywords

coronavirus; COVID; Next Generation; OCU500; Open-label; Phase I; vaccine

Outcome Measures

Primary Outcomes (8)

• Occurrence of abnormal clinical safety laboratory adverse events (AE).

  Through Day 8

• Occurrence of adverse events of special interest (AESI).

  Through 6 months post study product administration

• Occurrence of medically attended adverse events (MAAEs).

  Through 6 months post study product administration

• Occurrence of new-onset chronic medical conditions (NOCMCs).

  Through 6 months post study product administration

• Occurrence of serious adverse events (SAEs).

  Through 6 months post study product administration

• Occurrence of solicited local adverse events (AEs).

  Through Day 8

• Occurrence of solicited systemic adverse events (AEs).

  Through Day 8

• Occurrence of unsolicited adverse events (AEs).

  Through Day 29

Secondary Outcomes (6)

• Level of anti-vector antibodies

  Day 1 through Day 91

• SARS-CoV-2 anti-spike nasal mucosal binding Immunoglobulin A (IgA)

  Day 1 through Day 181

• SARS-CoV-2 anti-spike nasal mucosal binding Immunoglobulin G (IgG)

  Day 1 through Day 181

• SARS-CoV-2 anti-spike serum binding Immunoglobulin A (IgA) antibody

  Day 1 through Day 181

• SARS-CoV-2 anti-spike serum binding Immunoglobulin G (IgG) antibody

  Day 1 through Day 181

Study Arms (4)

Arm 1

EXPERIMENTAL

A single dose of 1×10\^10 viral particles (VP) in 100 uL of OCU500 administered via inhalation on Day 1 in participants from 18 to 64 years of age. N = 20

Biological: OCU500

Arm 2

EXPERIMENTAL

A single dose of 1×10\^10 viral particles (VP) in 100 uL of OCU500 administered intranasally (0.05 mL/nostril) on Day 1 in participants from 18 to 64 years of age. N = 20

Biological: OCU500

Arm 3

EXPERIMENTAL

A single dose of 5x10\^10 viral particles (VP) in 100 uL of OCU500 administered via inhalation on Day 1 in participants from 18 to 64 years of age. N = 20

Biological: OCU500

Arm 4

EXPERIMENTAL

A single dose of 5x10\^10 viral particles (VP) in 100 uL of OCU500 administered intranasally (0.05 mL/nostril) on Day 1 in participants from 18 to 64 years of age. N = 20

Biological: OCU500

Interventions

OCU500 BIOLOGICAL

OCU500 is a monovalent, replication-defective, chimpanzee adenovirus (ChAd36)-vectored COVID-19 vaccine that encodes a codon-optimized, stabilized prefusion form of the spike (S) protein from the Omicron XBB1.5 strain.

Arm 1; Arm 2; Arm 3; Arm 4

Eligibility Criteria

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

You may qualify if:

• Provides written informed consent before initiation of any study procedures.
• Able to understand and agree to comply with planned study procedures and be available for all study visits.
• Non-pregnant adults, 18 through 64 years of age at the time of study product administration.
• Participants of childbearing potential\* must agree to use or have practiced true abstinence\*\* or use at least one acceptable primary form of contraception.\*\*\*
• \*These criteria apply to females who are in a heterosexual relationship and are of childbearing potential. Not of childbearing potential include post-menopausal females (defined as having a history of amenorrhea for at least one year) or a documented status as being surgically sterile (hysterectomy, bilateral oophorectomy, or tubal ligation/salpingectomy).
• \*\*True abstinence is 100 percent of the time, no sexual intercourse (penis enters the vagina). Periodic abstinence \[e.g., calendar, ovulation, symptothermal, post-ovulation methods\] and withdrawal are not acceptable methods.
• \*\*\*Acceptable forms of primary contraception include a monogamous relationship with a vasectomized partner who has been vasectomized for 180 days or more before the participant's study product administration, a copper intrauterine device, a levonorgestrel-releasing intrauterine device, a progestin-only oral contraceptive pill, a depot medroxyprogesterone injection, or a progestin implant. Combined hormonal contraceptives containing estrogen, including combined oral contraceptive pills, transdermal patches, and vaginal rings, are not acceptable for this trial. Must have used at least one acceptable primary form of contraception for at least 30 days before study product administration and agree to continue at least one acceptable primary form of contraception through 60 days after study product administration.
• Participants of childbearing potential must have a negative urine pregnancy test at screening and within 24 hours before study product administration.
• In general, good health.\*
• Receipt of a complete primary COVID-19 vaccine series and at least one booster\* with last vaccination at least 16 weeks before study product administration.
• \*Booster may be either homologous or heterologous to the primary vaccine series. It must be an FDA-authorized/licensed vaccine, though doses may have been received as part of a clinical trial.
• Clinical screening laboratory evaluations are within normal reference ranges or grade 1 with no clinical significance (NCS) per investigator discretion.\*
• Must agree to have samples stored for secondary research.
• Must complete a Test of Understanding (ToU) before enrollment by answering 90 percent of questions correctly at least once in 3 attempts.

You may not qualify if:

• Positive SARS-CoV-2 PCR at screening.
• Abnormal vital signs (Grade 1 or higher).\*
• \*Grade 1 or higher is equivalent to: Systolic blood pressure (SBP) = 141 mmHg or = 89 mmHg Diastolic blood pressure (DBP) = 91 mmHg Heart rate (HR) is = 101 beats per minute or = 54 beats per minute Oral temperature = 38.0 degrees Celsius (100.4 degrees Fahrenheit)
• History of SARS-CoV-2 infection within the prior 16 weeks OR receipt of any COVID-19 vaccine within the prior 16 weeks before study product administration.
• Participant who is pregnant or breastfeeding or less than 12 weeks post partum at the time of study product administration.
• Participant has donated blood or plasma within 4 weeks prior to study product administration, or does not agree to refrain from blood or plasma donation until Day 181.
• Receipt of antibody or blood-derived products within 90 days before study product administration.
• Any significant medical or psychiatric diseases or any other condition that, in the opinion of the site PI or appropriate sub-investigator, precludes study participation.\*
• \*Significant self-reported or medically reported medical or psychiatric conditions include, but are not limited to drug or alcohol abuse within 6 months of enrollment, significant kidney disease, liver disease, history of hematologic malignancies, ongoing malignancy or recent diagnosis of malignancy in the last five years, excluding treated basal cell and squamous cell carcinoma of the skin, and cervical carcinoma in situ, which are allowed.
• Any respiratory disease, including but not limited to chronic obstructive pulmonary disease (COPD), asthma, interstitial lung disease, bronchiectasis, etc.
• Neurological or neurodevelopmental conditions.\*
• \*These conditions include: history of Bell's palsy, history of four or more migraine headaches in the past 12 months that interfered with normal daily activity or any migraine headache in the past 5 years that required emergency or inpatient medical care, epilepsy, seizures in the last 5 years, encephalopathy, focal neurologic deficits, Guillain-Barré syndrome, myelopathy, peripheral neuropathy, encephalomyelitis, transverse myelitis, stroke or transient ischemic attack, multiple sclerosis, Parkinson's disease, amyotrophic lateral sclerosis, Creutzfeldt-Jakob disease, or Alzheimer's disease.
• Cardiovascular disease (e.g., congestive heart failure, cardiomyopathy, ischemic heart disease), including any history of myocarditis or pericarditis, or uncontrolled cardiac arrhythmia.
• Any autoimmune disease, including hypothyroidism without a defined non-autoimmune cause.
• Any significant nasal or upper airway disease.\*

Sponsors & Collaborators

• National Institute of Allergy and Infectious Diseases (NIAID): lead

Study Sites (5)

The Hope Clinic of Emory University

Decatur, Georgia, 30030-1705, United States

NOT YET RECRUITING

University of Maryland, School of Medicine, Center for Vaccine Development and Global Health

Baltimore, Maryland, 21201-1509, United States

RECRUITING

Brigham and Women's Hospital

Boston, Massachusetts, 02115-6110, United States

NOT YET RECRUITING

Washington University School of Medicine in St. Louis - Infectious Disease Clinical Research Unit

St Louis, Missouri, 63110, United States

WITHDRAWN

University of Texas Medical Branch

Galveston, Texas, 77555-0435, United States

NOT YET RECRUITING

MeSH Terms

Conditions

COVID-19; Coronavirus Infections

Condition Hierarchy (Ancestors)

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

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SEQUENTIAL
• Sponsor Type: NIH
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 10, 2026
• First Posted: April 17, 2026
• Study Start: May 4, 2026
• Primary Completion (Estimated): April 29, 2027
• Study Completion (Estimated): November 1, 2027
• Last Updated: May 6, 2026

Record last verified: 2026-04

Locations

US (5)