China's First Monkeypox Vaccine Begins Phase I Clinical Trials in Henan Province

The Shanghai Institute of Biological Products Co has initiated phase I clinical trials for China's first monkeypox vaccine in Zhengzhou, the capital city of Henan Province. This vaccine, which utilizes a modified vaccinia virus Ankara (MVA) strain, has officially been authorized for clinical trials by the National Medical Products Administration in China. The research team plans to enroll a total of 120 volunteers, specifically targeting healthy individuals, men who have sex with men, and individuals living with HIV.

Participants in the trial must meet certain health criteria, including a body temperature below 37.3 C at the time of enrollment. Furthermore, individuals vaccinated against smallpox must have been born before 1980. Male participants and women of childbearing age are required to avoid conception for six months and to use effective contraceptive measures during this time. The deadline for volunteer enrollment is set for August 21, 2025.

As a viral zoonotic disease, monkeypox is transmitted through various means such as direct skin contact, respiratory droplets, and sexual activity. While the clinical symptoms of monkeypox are milder compared to smallpox, with a lower mortality rate ranging from 1% to 10%, some signature symptoms include swollen lymph nodes. The World Health Organization has recommended vaccination for close contacts of infected individuals and those in high-risk groups, which includes men who have sex with men, healthcare workers, and laboratory personnel.

The safety and efficacy of the newly developed vaccine have been supported by compelling clinical data and preclinical studies that showcase its ability to provide robust immunity against monkeypox in animal models. Although no monkeypox vaccine is currently available for commercial use in China, two vaccines, JYNNEOS and ACAM2000, have been authorized by the US Food and Drug Administration for at-risk adults in the United States. Both serve as preventative measures against mpox and smallpox, with JYNNEOS being a live virus vaccine and ACAM2000 being a live replicating vaccine, each with specific population restrictions identified by health agencies.