Chemoprophylaxis of leprosy with rifampicin in contacts of multibacillary patients: study protocol for a randomized controlled trial

Abstract

BackgroundThe annual new-case detection rate for leprosy, while generally stable over the last decade, shows that transmission rates have remained stagnant despite the successful worldwide administration of multidrug therapy since the 1980s. As such, novel control strategies are urgently needed. Focusing on managing leprosy patient contacts, the most susceptible to contracting the disease, has been seen as a potential strategy in limiting the spread of leprosy as shown by a number of recent epidemiological studies. Immunoprophylaxis with Bacillus Calmette-Guérin (BCG) has been seen as an effective preventive measure due to its ability to stimulate the development of cellular immunity which is essential in controlling the disease, especially in its multibacillary (MB) forms. The association of immunoprophylaxis with chemoprophylaxis in a single dose of rifampicin has been shown to be a promising preventive strategy, although a variety of studies have found instances of early case detection just a few months after BCG vaccination.Methods/designThe present study is a phase IV chemoprophylactic clinical trial consisting of administration of a single dose of rifampicin in MB leprosy patient contacts under care at the Souza Araújo Outpatient Clinic/FIOCRUZ as part of a randomized (2:1), double-blind, placebo-controlled study. It is comprised of two groups: 1) rifampicin + BCG; and 2) placebo + BCG.DiscussionThe aim is to evaluate whether the use of chemoprophylaxis with a single dose of rifampicin in MB leprosy patient contacts prior to the BCG vaccine would be able to prevent the onset of leprosy in those cases that may occur just a few months after vaccination. Contact subclinical infections (polymerase chain reaction) and the immunological parameters (anti-PGL-1, anti-LID-1, and IFN-γ) will be evaluated and the results will be compared after 12 months of follow-up.Trial registrationThe Brazilian Registry of Clinical Trials (ReBEC), RBR-69QK5P. Retrospectively registered on 1 June 2017.Electronic supplementary materialThe online version of this article (10.1186/s13063-018-2623-6) contains supplementary material, which is available to authorized users.

Social and environmental conditions related to Mycobacterium leprae infection in children and adolescents from three leprosy endemic regions of Colombia

“…Our findings are therefore compatible with both our previous research as well studies in Brazilian populations. As a pre-emptive approach to reduce the emergence of new cases and enable M. leprae elimination, it has recently been suggested that seropositive individuals that have asymptomatic or sub-clinical M. leprae infection receive BCG re-vaccination as well as treatment with rifampicin to serve as an early intervention to alter the natural course of infection [23, 24]. Our data provide further evidence for the implementation of prophylactic measures within high risk juvenile and other HHC populations.…”

High-risk areas of leprosy in Brazil between 2001-2015

“…Immunoprophylaxis with Bacillus Calmette-Guérin (BCG) is considered an effective preventive measure in the control of the disease due to its ability to stimulate the development of cellular Immunity (27) . The Ministry of Health recommends that BCG be administered in contacts without the presence of signs and symptoms of leprosy and respecting the criteria of vaccination history (15) .…”

“…The Ministry of Health recommends that BCG be administered in contacts without the presence of signs and symptoms of leprosy and respecting the criteria of vaccination history (15) . More recently, it has been shown that chemoprophylaxis in a single dose of rifampicin also consists of a promising measure to prevent the disease (27) .…”

Quantitative PCR for leprosy diagnosis and monitoring in household contacts: A follow-up study, 2011–2018

“…Active search for new cases among household contacts (HHC) is cost-effective since it can detect patients exhibiting early disease stages 5,6 . Large-scale public policies such chemo and/or immunoprophylactic strategies in HHC are effective 7–9 in decreasing the disease as a public health problem.…”