Randomized Trial to Evaluate the Efficacy/Effectiveness, Safety, and Immunogenicity of Replicative Live Attenuated Vaccinia Virus Vaccine LC16m8 for Prevention Against Mpox in High-risk Populations During Vaccination Deployment in Colombia

PI-UN-1760

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.

2023-12-16

2024-08-22

2024-12-06

Recruiting

Early phase I

8686

1. Inclusion Criteria: 1. Sex: Males and females 2. Age: ≥18 and ≤ 50 years old 3. Persons must be willing and sign the Informed Consent (I.C.). 4. Any of the following conditions including clinical conditions /manifestation: * People living with the HIV, with stable infection determined by participant´s being on antiretroviral therapy with a blood CD4+ cell count, ≥ 200 cells/mm3 in the last six months before study enrolment 5. Persons that use PrEP (HIV Pre-exposure prophylaxis). 6. Homosexual, Bisexual, or other men who have sex with men (MSM) with multiple sexual partners. Commercial sex workers (CSW) and partners CSW 7. A female participant is eligible to participate if the participant meets one of the inclusion criteria numbered -1, -2 or -3 above. The participant cannot be pregnant or lactating. Additionally, the female participant must meet one of the following conditions: * The participant has non-childbearing potential. To be considered of non-childbearing potential, a female must be post-menopausal for at least one year or surgically sterile. OR * The participant has a childbearing potential and agrees to use an effective contraceptive method or abstinence from at least 4 weeks before the vaccine administration until at least 2 months after the administration and have a negative highly sensitive pregnancy test (urine or serum as required by local regulation) within 10 days before vaccination. 2. Exclusion Criteria: 1. Subjects with an acute and/or severe disease. 2. Subjects with a terminal disease. 3. Subjects with a medical record of anaphylaxis caused by any of the vaccine's excipients or with previous undesired reactions to other vaccines such us (Allergic reactions, Guillain barre syndrome, Varicella zoster, or shingles). 4. Previous medical record of Mpox. 5. Subjects living with HIV with a CD4+ T cell count of fewer than 200 cells/mm3. 6. Pregnant or breastfeeding woman. 7. Active or medical record of atopic dermatitis or eczema, or with close contact with someone with an active or medical record of atopic dermatitis or eczema. 8. The presence of a skin condition with extensive breaks in the skin, such as burns, impetigo, contact dermatitis, or zoster (shingles), is not likely to heal by the day of vaccination. 9. Using immunosuppressive medications, in eye drops, by mouth, or topically (nasal sprays and inhaled corticosteroids are permissible). 10. Active or past malignancy except for cutaneous basal or squamous cell carcinomas. 11. An Autoimmune disease. 12. Medical record of heart condition under the care of a physician. 13. Medical record of splenectomy. 14. Medical record of solid organ or bone marrow transplantation. 15. Medical record of keloid scar development 16. Evidence of immunosuppression, cardiac disease, renal disease, or unstable medical condition as determined by baseline medical history, physical assessment, and laboratory assessment. 17. Psychiatric condition that precludes compliance with the protocol. 18. People who received or plan to receive licensed live vaccines 30 days before or after study vaccination. 19. People who received or planned to receive immunoglobulin or other blood products 60 days before HIV screening. 20. People who received or plan to receive experimental drugs/vaccines 30 days before study vaccination or before study completion. 21. People who received or planned to receive systemic immunosuppressive therapy and radiation therapy 30 days before or after the study vaccination. 22. Use of systemic chemotherapy within five years before the study vaccination. 23. Medical record of smallpox vaccination and/or evidence of scarring at the vaccination site. 24. Allergies to streptomycin sulfate and/or erythromycin lactobionate.

{'studyType': 'INTERVENTIONAL', 'phases': ['PHASE3'], 'designInfo': {'allocation': 'RANDOMIZED', 'interventionModel': 'PARALLEL', 'interventionModelDescription': 'Vaccinate LC16m8 randomly assigned to two groups consisting of two groups of Immediate and Delayed vaccination 1:1 with a follow-up period of 180 days to evaluate newly MPXV-infected cases as well as immuno-responses including neutralizing antibody titers.', 'primaryPurpose': 'PREVENTION', 'maskingInfo': {'masking': 'NONE'}}, 'enrollmentInfo': {'count': 8686, 'type': 'ESTIMATED'}}

2024-01-29