December 19, 2023

Development of the candidate tuberculosis vaccine H56:IC31 ended based on early data from the Prevention of Recurrence TB Consortium

Vaccine well tolerated and demonstrated immunogenicity but did not provide protection against TB recurrence; participants being informed; further analysis continues.

POR Consortium LogoThe first analyses of data from the Phase IIb vaccine trial A-055 show that the tuberculosis (TB) vaccine candidate, H56:IC31, was well tolerated and demonstrated an immune response compared to the placebo in participants, all of whom had previously had TB. However, the primary analysis showed it did not provide protection against TB recurrence, reported Statens Serum Institut (SSI), IAVI, and trial partners who are part of the Prevention of Recurrence (POR) TB Consortium today. Based on these trial data, SSI has stopped development of the vaccine.

A supporting analysis points in the direction of an increased rate of TB recurrence among people who received the study vaccine (5.8%) compared to people who received the placebo (3.4%), although this cannot be concluded with certainty. Analyses are ongoing, including to understand whether people in one group were, by chance, more likely to get recurrent TB even before the vaccination.

Read the press release.