Background:

In Australia, the population at greatest risk of tuberculosis is migrants from high-prevalence countries, among whom TB infection (TBI) is common. The most frequently used  treatments for TBI in Australia are six to nine months of daily isoniazid (6-9H) or 4 months of daily rifampicin (4RIF). Clinical trials have also shown that the combination regimen of isoniazid and rifapentine administered weekly for 12 weeks (3HP) was as effective as 9H alone. However, the adherence to 3HP has not been directly compared with 4 month rifampicin therapy.

Aim:

The primary objective of this study was to evaluate feasibility of using 3HP for the treatment of TBI in Sydney, Australia.

Methods:

This is analysis describes initial findings of a multi-centre, prospective, open-label, randomised trial conducted among individuals with TBI. In the parent study, participants were randomised to weekly rifapentine and isoniazid administered for 12 weeks or daily rifampicin for 4 months. Treatment with 3HP was monitored via weekly SMS. Patients with TBI in 9 clinics in New South Wales were enrolled between from March 2019 and June 2022. 

Results:

The study randomised 52 patients to the 3HP arm. The median age was 33 years (interquartile range: 15.5), 27/52 (51.9%) were female, 38/52 (73.1%) had positive interferon gamma release assay (IGRA) test. The main reason for testing was pre-employment screening and contact investigation. 44/52 (84.6%) of the patients completed the therapy, 5/52 (9.6%) stopped the therapy due to adverse event (AE). 40/52 (76.9%) of patients would recommend this treatment.

Conclusion:

This study demonstrated the feasibility and acceptability of the 3HP regimen in an Australian context.