NCT05762523

Safety and Tolerability Study of the VAC∆6 Vaccine in Volunteers Aged 18-40 Years

Completed Phase 1 Last updated 9 March 2023

What this trial tests

Phase 1 trial testing VAC∆6 vaccine - оnce at a dose of 10⁶ PFU in Smallpox in 60 participants. Completed in 27 January 2020.

Timeline

18 May 2019

Primary endpoint
22 July 2019

27 January 2020

Quick facts

Lead sponsor	Federal Budgetary Research Institution State Research Center of Virology and Biotechnology "Vector"
Phase	Phase 1
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	none
Primary purpose	prevention
Enrollment	60
Start date	18 May 2019
Primary completion	22 July 2019
Estimated completion	27 January 2020
Sites	1 location across Russia

Drugs / interventions tested

• VAC∆6 vaccine - оnce at a dose of 10⁶ PFU — full drug profile →
• VAC∆6 vaccine - once at a dose of 10⁷ PFU — full drug profile →
• VAC∆6 vaccine - twice at a dose of 10⁶ PFU — full drug profile →
• Live smallpox vaccine (Smallpox vaccine) + The OspaVir® inactivated smallpox vaccine — full drug profile →

Conditions studied

• Smallpox — all drugs for Smallpox →
• Monkeypox — all drugs for Monkeypox →
• Cowpox — all drugs for Cowpox →
• Vaccinia Virus Infection — all drugs for Vaccinia Virus Infection →

Sponsor

Federal Budgetary Research Institution State Research Center of Virology and Biotechnology "Vector" — full company profile →

Who can join

Adults 18 to 40, any sex, with Smallpox or Monkeypox. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

The aim of the clinical study is to study the safety and tolerability of the live cell-based vaccine against smallpox and other orthopoxvirus infections (VAC∆6 vaccine) based on vaccinia virus, in intracutaneous administration.

The research tasks are to:

* evaluate the safety of various schemes for the use of the VAC∆6 vaccine using a set of clinical and laboratory-instrumental methods (thermometry, blood pressure registration, auscultation of the heart and lungs, electrocardiography (ECG), complete blood count and common urine test, biochemical, immunological, and virological studies);
* evaluate the reactogenicity of various schemes for the use of the VAC∆6 vaccine (taking into account the number of local and systemic reactions, the percentage of those vaccinated with various degrees of manifestation of systemic and local reactions);
* evaluate the possibility of virus shedding into the environment by volunteers;
* evaluate the immunological efficacy of various vaccine administration schemes;
* identify the development of undesirable reactions to the administration of the vaccine;
* evaluate the cellular immune response to the introduction of various schemes for the use of the vaccine;
* evaluate preliminary efficacy data in order to select an optimal scheme for the administration of the vaccine to make a decision on conducting Phase II clinical trials in an extended group of volunteers.

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. Advancements in monkeypox vaccines development: a critical review of emerging technologies.
   Garcia-Atutxa I, Mondragon-Teran P, Huerta-Saquero A, Villanueva-Flores F. · · 2024 · cited 18× · PMID 39464881 · DOI 10.3389/fimmu.2024.1456060
2. Evaluating the advancements and efficacies in pharmacological Mpox treatments: a comprehensive review.
   Hudu SA, Saadi N, Tahir A, Jimoh AO, et al · · 2025 · cited 1× · PMID 41098827 · DOI 10.3389/fphar.2025.1654467
3. Emerging threats of monkeypox virus in 2024: current insights and future directions.
   L S D, R D, A M, N H, et al · · 2025 · PMID 41173508 · DOI 10.1080/20565623.2025.2577069