Efficacy/Effectiveness, Safety, and Immunogenicity of LC16m8 Mpox Vaccine in Colombia

Summary

Background: Mpox is a zoonotic disease caused by the mpox virus (MPXV). It has been endemic in West and Central African countries. However, the soaring number of those has been reported in non-endemic countries since May 2022, making World Health Organization (WHO) declare a global mpox Public Health Emergency of International Concern in July 2022. Those with mpox are primarily young men (96%, and median age of 34 \[interquartile range (IQR):29-41 years\]), and 84% are self-identified homosexual, bisexual, and men who have sex with men (MSM) . Furthermore, about half of these mpox cases with known human immunodeficiency virus 1(HIV-1, hereafter shown as HIV). WHO recommended prioritizing vaccinating those populations as high-risk populations, including those with HIV, since they will be severely ill if infected mpox virus (MPXV). The smallpox vaccine is expected to offer cross-immunity against MPXV. Under these circumstances, WHO included LC16m8 in the recommended vaccine lists for mpox as the product is expected to have cross-efficacy and immunogenicity against MPXV. Additionally, the safety profile was demonstrated in both adults and children, including infants who have low immuno-functions. Given that Colombia has the fifth highest mpox prevalence worldwide, WHO encouraged the authorities to implement vaccine programs while evaluating the safety and efficacy of LC16m8 as collaborative research. Following WHO initiative, this study is being conducted with the collaboration of various experts from Colombia and Japan on a large scale, with vaccine contributions and funding from Japan and Colombia However, the current infection situation differs from six months ago, and there have been few recent cases of MPXV infection in the country.

Primary objective: To determine the efficacy of the replicating attenuated live vaccinia virus vaccine LC16m8 against laboratory-confirmed mpox and safety in a Colombian population with a high risk of being infected with MPXV(See the Inclusion Criteria), by comparing the immediate vaccination group and the delayed vaccination groups to assess safety and tolerability until 180 days after vaccination. Study design: An open randomized deployment study (1:1 Immediate and Delayed vaccination group).

Study population: People at high risk of serious illness if infected with MPXV and those who engage in risk behaviors for acquiring MPXV infection.

Conditions

• Monkeypox

Interventions

BIOLOGICAL

LC16m8

LC16m8 should be stored at temperatures between -35°C and -20°C. The product should not be stored at temperatures below -35°C, because deterioration or damage of the rubber stopper could occur. The virus in this product is sensitive to sunlight and is quickly inactivated, so care should be taken to avoid exposure to light, both before or after reconstitution. Carefully examine the content at the time of reconstitution. Do not use if precipitation, contamination of foreign substances, or other abnormalities are observed. This product should be dissolving the drug immediately before inoculation. Once dissolved, it should be used immediately. Since this product does not contain thimerosal, once the stopper is removed, any solution remained in the vial must be disposed of. Do not restore or reuse the remaining solution. Shelf Life: 10 years from the date of passing the national test for lot-release Bottle containing about 250 doses

Sponsors & Collaborators

• Ministerio de Salud y Protección Social de Colombia

  collaborator UNKNOWN

• Ministry of Health, Labour and Welfare, Japan

  collaborator OTHER_GOV

• Japan Agency for Medical Research and Development

  collaborator OTHER_GOV

• National Center for Global Health and Medicine, Japan

  collaborator OTHER_GOV

• National Institute of Infectious Disease, Japan

  collaborator UNKNOWN

• Instituto Nacional de Salud

  collaborator UNKNOWN

• Universidad Nacional de Colombia

  lead OTHER

Principal Investigators

• Carlos A Álvarez · Universidad Nacional de Colombia

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

50 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-12-16

Primary Completion

2024-08-20

Completion

2025-12-31

Countries

• Colombia

Study Locations