MVA85A (

modified vaccinia Ankara Modified vaccinia Ankara (MVA) is an attenuated (weakened) strain of the vaccinia virus. It is being used as a vaccine (called MVA-BN, brand names: Imvanex in the EU, Imvamune in Canada, and Jynneos in the US) against smallpox and monkeypox, havi ...

85A) is a vaccine against

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in w ...

developed by researchers led by Professor Helen McShane at

Oxford University Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the Un ...

. This vaccine produces higher levels of long-lasting cellular immunity when used together with the older TB vaccine BCG. Phase I clinical trials were completed and then phase II clinical trials took place in

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

. Efficacy trials ran in parallel from 2009 to 2019. Results released in February 2013, were described as "disappointing", showing only a statistically insignificant prevention rate in infants. Results published in 2015, cast doubt on the efficacy of the vaccine. In 2018, a ''BMJ'' investigation raised concerns about the ethics of an efficacy trial in South African infants, particularly because of results from earlier animal trials such as a study with

macaque The macaques () constitute a genus (''Macaca'') of sociality, gregarious Old World monkeys of the subfamily Cercopithecinae. The 23 species of macaques inhabit species distribution, ranges throughout Asia, North Africa, and (in barbary macaques ...

s at

Porton Down Porton Down is a science park in Wiltshire, England, just northeast of the village of Porton, near Salisbury. It is home to two British government facilities: a site of the Ministry of Defence's Defence Science and Technology Laboratory (Dstl) ...

. One response argued that 14 prior human trials showed a safety signal, that regulators were aware of the primate trial and decided to continue, and that three subsequent investigations found no evidence of wrong-doing. Another response by Ian Orme questioned the critique of animal models.

References

External links

New TB vaccine shown to be safe
Tuberculosis vaccines {{vaccine-stub