Monovalent Chimpanzee Adenoviral-Vectored Sudan Ebolavirus Vaccine in Healthy Adults

NCT06036602 | Completed Phase 2 DMC FDA Drug

• 1 other identifier: Sabin-003
• Study Type: interventional
• Target: 125
• Locations: 2 countries
• Sites: 2

Brief Summary

A Phase 2, Randomized, Double-blind, Placebo-Controlled Trial to Evaluate Safety, Tolerability, and Immune Responses of an Investigational Monovalent Chimpanzee Adenoviral-Vectored Sudan Ebolavirus Vaccine in Healthy Adults

Conditions

Ebola Sudan Virus Disease

Keywords

Sudan Ebolavirus (SUDV); Sudan Ebolavirus Vaccine; cAD3-Ebolavirus Vaccine

Outcome Measures

Primary Outcomes (1)

• To evaluate the safety and tolerability of cAd3-Sudan Ebolavirus vaccine through the assessment of SAEs, solicited AEs, unsolicited AEs, AESI, MAAE, and AE

  Count and percentage of vaccinated participants who develop: * serious adverse events (SAEs), * solicited adverse events (AEs), * unsolicited AEs, * adverse event of special interest (AESI), * medically attended adverse events (MAAE), * AE at each intensity level. Estimand 1a (Primary): Count and percentage of vaccinated participants who would develop SAEs, solicited AEs, unsolicited AEs, AESI, MAAE, and AE at each intensity level will be evaluated with each treatment group. A treatment policy strategy is used for assessing safety irrespective of a current (or prior) infection at time of the vaccination. Infections and death (if they meet the AE and time window criteria) are included in the endpoint (composite strategy).

  1 year

Secondary Outcomes (1)

• To evaluate the antibody response (IgG) to cAd3-EBO S vaccine at Day 29 post-vaccination.

  1 month

Study Arms (2)

cAD3-Sudan Ebolavirus Vaccine

EXPERIMENTAL

Single dose of cAd3-Sudan Ebolavirus vaccine (1x10\^11 PU) administered intramuscularly (IM) with needle and syringe.

Biological: cAD3-Sudan Ebolavirus Vaccine

Placebo

PLACEBO COMPARATOR

0.9% NaCl solution for injection)administered intramuscularly (IM) with needle and syringe in a volume of 0.56 mL

Other: Placebo

Interventions

cAD3-Sudan Ebolavirus Vaccine BIOLOGICAL

The recombinant chimpanzee adenovirus Type 3-vectored Sudan Ebolavirus vaccine, (cAd3-EBO S) is composed of a cAd3 vector that expresses wild type glycoprotein (WT GP) from the Sudan Gulu ebolavirus strain.

cAD3-Sudan Ebolavirus Vaccine

Placebo OTHER

0.9% NaCl solution for injection.

Placebo

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Able and willing to complete and provide written informed consent prior to any study procedure; including injection site photograph consent, completing an Assessment of Understanding (AoU) prior to enrollment by answering 9 out of 10 questions correctly at least once in 3 attempts, and including optional consent for retention of blood samples for potential future testing and assay development. Note: Participants can be enrolled even if they do not provide optional consent for retention of blood samples for potential future testing and assay development.
• Able to read and write the language used in diary card.
• Male or non-pregnant female 18 to 70 years of age (inclusive) at time of informed consent.
• Is capable of understanding and agrees to comply with planned study procedures and to be available for all clinic follow-up for all planned study visits.
• Able to provide proof of identity to the satisfaction of the study clinician completing the enrollment process.
• Has a means to be contacted and to contact the investigator during the study.
• Agree not to receive any vaccine within 28 days from study vaccination (prior and after), with the exception of an emergency use authorization or authorized non-adenoviral vectored COVID-19 vaccine, which may be given within 14 days of study vaccination.
• Agree not to donate bone marrow, blood, or blood products until 3 months after the study vaccination.
• In good general health without clinically significant medical conditions, based on medical history, physical examination, vital signs, and clinical laboratory results as deemed acceptable by the principal investigator.
• Clinical laboratory results within 28 days prior to vaccination within the site's laboratory reference ranges (or deemed not clinically significant by the principal investigator) for the following parameters: hematology (CBC including hemoglobin, WBC, RBC, total lymphocyte count); coagulation tests (prothrombin time, INR, fibrinogen); chemistry (C-reactive protein, d-dimer, ALT, AST, and serum creatinine). A laboratory result that is outside the reference range and is deemed not clinically significant by the principal investigator will not exclude the participant.
• Has a BMI \>17 and ≤37 at screening.
• Female participant-specific criteria:
• Negative pregnancy serum test at screening, and negative urine pregnancy test before vaccination, if of reproductive potential.
• Agrees to use an effective means of birth control from at least 21 days prior to enrollment through 24 weeks after study vaccination if assessed to be woman of childbearing potential UNLESS they fulfill one of the following criteria:
• At least 1 year postmenopausal.

You may not qualify if:

• Pregnant or lactating female or plans to become pregnant or breastfeed starting from study vaccination through to study end.
• Has any medical disease or condition that, in the opinion of the investigator, precludes study participation. This includes any acute, subacute, intermittent, or chronic medical disease or condition that:
• would place the participant at an unacceptable risk of injury,
• render the participant unable to comply with the requirements of the protocol,
• or may interfere with the evaluation of responses or the participant's successful completion of the trial (chronic conditions that are well-controlled and medically stable, i.e., no change in treatment for medical reasons occurred in the last 6 months and are allowed at the discretion of the principal investigator, e.g., hypertension, asthma, thyroid disease). The medical disease or condition also includes any confirmed or suspected immunosuppressive or immunodeficient conditions resulting from disease (e.g., malignancy, HIV infection) or immunosuppressive/cytotoxic therapies (e.g., medications used during cancer chemotherapy, organ transplantation or to treat autoimmune disorders).
• Serology screen positive for infectious diseases (hepatitis B, hepatitis C, HIV 1 and 2, syphilis).
• Known history of prior exposure to SUDV or prior diagnosis of SUVD.
• Current diagnosis of COVID-19 by Reverse Transcription Polymerase Chain Reaction (RT-PCR) or antigenic testing or current signs and symptoms of COVID-19. Participants may be enrolled 14 days post resolution of all signs and symptoms of COVID-19 or of testing positive for COVID-19 in asymptomatic participants.
• History of or active status of any of the following clinically significant conditions:
• Serious adverse reactions to vaccines such as anaphylaxis, urticaria (hives), respiratory difficulty, angioedema, or abdominal pain.
• Allergic reaction to excipients in the study vaccine including gentamycin, neomycin or streptomycin or any other aminoglycoside.
• Diabetes mellitus type 1 or type 2.
• Active tuberculosis.
• Hereditary angioedema, acquired angioedema, or idiopathic forms of angioedema.
• Idiopathic urticaria within the last year.

Sponsors & Collaborators

• Albert B. Sabin Vaccine Institute: lead
• Biomedical Advanced Research and Development Authority: collaborator

Study Sites (2)

KEMRI/Centre for Respiratory Disease Research Siaya Clinical Research Annex

Siaya, Kenya

Location

Makerere University-Walter Reed Project

Kampala, Uganda

Location

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants will be randomized 4:1 to receive the cAd3-Sudan Ebolavirus vaccine at 1.0 × 10\^11 PU dose or placebo at Day 1.

Study Record Dates

• First Submitted: August 21, 2023
• First Posted: September 14, 2023
• Study Start: July 15, 2024
• Primary Completion: November 8, 2025
• Study Completion: November 8, 2025
• Last Updated: March 4, 2026

Record last verified: 2025-01

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL

Locations

KE (1); UG (1)