MVA85A vaccine to enhance BCG for preventing tuberculosis

What is the aim of this review?

The aim of this Cochrane review was to evaluate the effectiveness and safety of using MVA85A in addition to BCG compared to using BCG alone for the prevention of tuberculosis.

Key messages

MVA85A in addition to BCG showed no added benefit to BCG in the prevention of acquiring tuberculosis.

What was studied in the review?

Tuberculosis is an infectious airborne disease which affects the lungs and other organs in the body. It can either be active when a person shows signs and symptoms or has confirmatory tests for tuberculosis or latent when a person has inhaled the bacteria before but does not show signs and symptoms of sickness. Currently, there is only one vaccine licensed for prevention of this disease, which is called BCG. However, the ability for the BCG vaccine to prevent tuberculosis differs in different settings and patient groups resulting in tuberculosis still remaining a problem worldwide despite children being immunized. MVA85A is a vaccine that was investigated for the prevention of tuberculosis with the hope that when used in addition to BCG it will improve the prevention of people getting tuberculosis.

What are the main results of this review?

After examining the research published up to 10 May 2018, we included six study findings from four randomized controlled trials (clinical trials where people are randomly put into one of two or more treatment groups), enrolling 3838 children and adults. Based on these studies of mostly children and adults living in Africa, MVA85A added to BCG compared to BCG alone probably has no effect on the risk of developing active tuberculosis defined as microbiologically confirmed tuberculosis (moderate‐certainty evidence) or the risk of starting on tuberculosis treatment (moderate‐certainty evidence). MVA85A has no effect on the risk of developing latent tuberculosis (moderate‐certainty evidence). MVA85A does not cause any life‐threatening serious side effects (highly‐certainty evidence). There were more local skin reactions in people vaccinated with MVA85A, however, there was no increase in overall side effects in people given MVA85A.

How up‐to‐date is this review?

The review authors searched for studies that have been published up to May 2018.