Phase IIB Study of Recombinant Novel Coronavirus Vaccine

NCT05293223 | Completed Phase 2 DMC

• 1 other identifier: FH-63 (CS-nCoV-SeqAD26)
• Study Type: interventional
• Target: 88
• Locations: 1 country
• Sites: 3

Brief Summary

This is an open-label and non-randomized study to demonstrate the immunogenicity and safety profile in adults that received the Ad5-nCoV vaccine at least 21 days but no later than 90 days after the first dose of Sputnik V. The non-inferiority hypothesis is used for the evaluation of the exploratory objective. The ratio of Geometric mean titers (GMTs) of SARS-CoV-2 neutralizing antibody in participants on Day 21 post-vaccination of Ad5-nCoV (previously received a 1st dose of Sputnik V) (Group A) and two doses of Sputnik V (Group B) is used for the evaluation of this hypothesis. It is assumed to enroll about 100 subjects for each group. Additionally, 45 participants will be selected from Group A (to enter the immunogenicity subgroup for cellular immune response analysis. According to the above, considering extra subjects for compensating about 10% dropouts, the sample size of Group A is designed to be 450, for Group B is 200. Participants enrolled in Group A (1st dose of Sputnik V plus 1 dose of Ad5-nCoV) must have only received the 1st dose of Sputnik V and the interval between the previous injection (1st dose of Sputnik V) and the day of vaccination with Ad5-nCoV should be between 21 and 90 days. The comparator (Group B) will be the samples stored at the immunology lab of the Buenos Aires University Medical School, corresponding to individuals vaccinated with 2 doses of Sputnik V. UPDATE : It's worth noting that enrollment number during the study was lower than the originallyplanned. According to the Protocol Group A sample size was designed to be 450. A low enrollment rate due to a fast vaccination rate (second dose) through the national COVID vaccination campaign for the entire population of Argentina resulted in difficulties in reaching the sample size planned. (the final number of participants enrolled and vaccinated in the study was 86 in arm A ).The enrollment period was affected due to the fast expansion of the National Vaccination Plan and the opportunity for potential participants to access it. Therefore, it was not possible to achieve the number of enrolled participants that was planned at the beginning of the study (450).

Conditions

COVID-19 Vaccine

Outcome Measures

Primary Outcomes (1)

• The Geometric mean titers (GMTs) of SARS-CoV-2 neutralizing antibody

  The Geometric mean titers (GMTs) of SARS-CoV-2 neutralizing antibody on Day 21 post-vaccination of Ad5-nCoV.

  21 days from baseline

Secondary Outcomes (6)

• The Geometric mean titers (GMTs) of SARS-CoV-2 neutralizing antibody

  Month 3 and Month 6 from baseline

• solicited adverse events

  from baseline to 7 days post-vaccination

• SARS-CoV-2 specific T-cell response

  Day 21 post-vaccination of Ad5-nCoV

• The GMT of S-protein receptor binding domain (S-RBD) antibody

  Day 21, Month 3, and Month 6

• unsolicited adverse events (AEs)

  from baseline to 21 days post-vaccination

Study Arms (2)

Group A

EXPERIMENTAL

One dose Sputnik V + one dose Ad5-nCoV

Biological: Ad5-nCov

Group B

NO INTERVENTION

Samples stored at the immunology lab of the Buenos Aires University Medical School, corresponding to individuals vaccinated with 2 doses of Sputnik V.

Interventions

Ad5-nCov BIOLOGICAL

Participants enrolled in Group A with only the 1st dose of Sputnik V will receive Ad5-nCoV vaccine at least 21 days but no more than 180 days after the first dose. They will be followed to evaluate the immunogenicity and safety of Ad5-nCoV vaccine during 6 months

Group A

Eligibility Criteria

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

You may qualify if:

• Participants aged 18 years and above at the time of randomization.
• Provide written informed consent.
• Axillary temperature ≤ 37℃.
• Never received any investigational or licensed COVID-19 vaccine other than the 1st dose of Sputnik V with an interval of 21-90 days before the study.
• Subjects are eligible for immunization of this product as evaluated by investigators after medical history examination, physical examination and clinical judgment of health.

You may not qualify if:

• Have a history of seizures, epilepsy, encephalopathy, psychosis.
• History of anaphylaxis to any vaccine component.
• Positive urine pregnancy test result, pregnant, lactation women, or intend to become pregnant within the next 6 months.
• Congenital or acquired angioedema/neuroedema.
• Medical history of Guillain-Barré syndrome.
• Asplenia or functional absence of spleen.
• Bleeding disorder (e.g. protein S or factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venipuncture.
• Any confirmed or suspected immunosuppressive or immunodeficient state; received immunosuppressive therapy, cytotoxic therapy, or chronic corticosteroids (excluding corticosteroid spray therapy for allergic rhinitis and surface corticosteroid therapy for acute non-complicated dermatitis) within the past 6 months,
• History of chronic systematic infection.
• Administration of immunoglobulins and/or any blood products within three months prior to the planned administration of the vaccine candidate.
• Receiving anti-tuberculosis or cancer treatment.
• History of laboratory-confirmed COVID-19, or has a positive result at the examination of SARS-CoV-2 antigen before vaccination.
• Planned to receive any vaccine (licensed or investigational), other than the study intervention, within 14 days before and after study vaccination.
• Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran and edoxaban).
• Any other significant disease, disorder or finding which may significantly increase the risk to the volunteer because of participation in the study, and affect the ability of the volunteer to participate in the study or impair interpretation of the study data.

Sponsors & Collaborators

• Fundación Huésped: lead
• Dalhousie University: collaborator
• CanSino Biologics Inc.: collaborator

Study Sites (3)

Fundación Huésped

Ciudad Autónoma de Buenos Aires, Buenos Aires, 1202, Argentina

Location

Centro de vacunación PREVIVAX

Ciudad Autonoma de Buenos Aire, Ciudad Autónoam de Buenos Aires, 1414, Argentina

Location

Centro de Investigación y Prevención Cardiovascular CIPREC

Buenos Aires, 1119, Argentina

Location

MeSH Terms

Interventions

Ad5-nCoV vaccine

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PhD,Principal Investigator

Model Details: The ratio of Geometric mean titers (GMTs) of SARS-CoV-2 neutralizing antibody in participants on Day 21 post-vaccination of Ad5-nCoV (previously received a 1st dose of Sputnik V) (Group A) and two doses of Sputnik V (Group B) is used for the evaluation of this hypothesis.

Study Record Dates

• First Submitted: November 24, 2021
• First Posted: March 24, 2022
• Study Start: October 1, 2021
• Primary Completion: November 15, 2022
• Study Completion: December 15, 2023
• Last Updated: June 25, 2025

Record last verified: 2025-06

Locations

AR (3)