Phase IV, multi-site, unblinded, randomised trial of prophylactic daily rifampicin/isoniazid vs. weekly rifapentine/isoniazid for latent tuberculosis infection (LTBI)
Despite the availability of effective treatment for drug susceptible Mycobacterium tuberculosis, tuberculosis (TB) continues to cause significant morbidity and mortality worldwide.
In the UK, there has been a resurgence of TB over the last three decades with stabilisation of the rates of disease in the last five years at a level higher than most Western European countries.
Elimination requires a focus on sterilising the pool of latently infected individuals from which future TB cases would be generated.
A randomised pilot trial was designed to assess the safety and feasibility of treating adults between 16 and 65 years of age for Latent TB Infection (LTBI) in the UK context, with a relevant comparator regimen and a standardised treatment process and support in both arms without directly observed therapy (DOT).
The HALT LTBI Study is a Phase IV, unblinded, randomised, multi-site UK trial which recruited participants presenting with LTBI at TB clinics at both the Royal Free London Foundation NHS Trust and Barts Health NHS Trust in Newham.
Individuals who met the eligibility criteria and agreed to preventative therapy and to give their written consent to take part participated in the trial.
Recruited individuals were randomised to receive either a daily combination of rifampicin/isoniazid (‘standard’ practice) for 90 days (three months) versus a weekly combination of rifapentine/isoniazid (‘experimental’ practice), for 12 weeks.
Safety and feasibility was assessed with 52 patients. Multivariable logistic regression of the likelihood of completion of treatment and presence of adverse effects was undertaken.
We plan to now do a larger study, recruiting sufficient people (up to a further 400 participants) to assess differences in completion rates between two different treatments of about the same duration: the standard of care in the UK, consisting of daily rifampicin/isoniazid for 3 months vs. the novel regimen consisting of weekly rifapentine/isoniazid.