The Clinical Trial

The Prevention of Recurrence (POR) consortium aims to assess whether the TB vaccine H56:IC31 can protect against recurrent TB. We do this by conducting a clinical trial at four sites in South Africa and one site in Tanzania. We aim to include 900 patients with TB and within the final month of their 6 months treatment, participants will be randomized to vaccine or placebo and followed up for recurrent TB. The trial is a double blinded and none of the participants or investigators will know whether they received vaccine or placebo before after the completion of the trial.

The primary efficacy endpoint will be culture-confirmed TB recurrence any time from 14 days after receipt of the last vaccination through one year after last vaccination. Sputum will be obtained for culture when participants have signs or symptoms of TB identified during phone interviews, site visits, or at unscheduled visits prompted by the occurrence of TB signs and symptoms. At the final visit, a sputum sample for Mtb will be obtained from all participants capable of producing sputum, even if there is no clinical suspicion of TB disease.

The first 100 participants enrolled will have a follow-up for more intensive safety evaluations and samples collection for vaccine immunogenicity assessments. Safety will be monitored and reviewed on an ongoing basis. If a pausing or stopping rule is triggered, an independent Data Monitoring Committee (DMC) will interpret the findings.

Blood and sputum samples obtained from trial participants throughout the trial will used to identify correlates of protection and risk factors for TB recurrence.

At completion of the trial, we will be able to show if the vaccine is effectuations against recurrent TB - a major benefit to the 10 million TB patients diagnosed every year. We will have explored a new proof-of-concept trial design with potential to facilitate early vaccine development decisions. We will have completed capacity-building activities to expand TB vaccine trial capability in Sub Sahara Africa. Our detailed focus on correlate of protection discovery, will hopefully lay the foundation for future TB vaccine trials. Importantly, a successful POR vaccine may allow shortening of TB treatment regimens for drug resistant TB.