Independent Study to Establish the Efficacy of the Six Doses Uniform MDT Regimen (U-MDT) for Leprosy Patients

In the past both the treatment of new leprosy patients and the classification criteria for treatment purposes have gone through major changes. At the moment, newly diagnosed leprosy patients are classified into PB and MB based on the number of lesions only. More than 5 lesions leads to a classification as MB patient and treatment for 12 months with MDT composed of three drugs, i.e. rifampicin, dapsone and clofazimine. One to 5 lesions leads to a classification as PB patient and treatment for 6 months with MDT composed of two drugs, i.e. rifampicin and dapsone.

Despite all the favorable data from the point of view of practical application, this therapeutic regimen still presents some constraints, including the lengthy course of treatment. Especially in those situations where leprosy control is integrated into the general health services classification is a problem for the general health worker that has only received one or two days of training in leprosy.

A uniform regimen for leprosy would simplify treatment in the field. Results from control programs and research projects have demonstrated that relapse rates after MDT are extremely low, approximately 0.2% annually among MB cases on the 24-dose regimen. The low relapse rates indicate that there was room to shorten the course of MDT to less than 24 monthly-supervised doses of rifampicin plus self-administered doses of dapsone and clofazimine. Although some papers have suggested that relapse rates after MDT may be significantly higher in MB patients with an initial bacterial index equals or bigger than 3, the present diagnostic universe of leprosy includes few such patients, and the total number of relapses caused by them would account for a minimal percentage of cases in a control program. Since 1998, a 12-month treatment course for MB leprosy is advised by WHO. The main problem when evaluating any new treatment regimen for leprosy, is that there are no good and reliable data available for the current treatment regimen: relapse rates have never been systematically determined and the same holds true for reaction and nerve function impairment rates, the major cause of the nerve damage that leads to handicaps and deformities in leprosy patients.

Currently, WHO is exploring possibilities to introduce a short uniform treatment regimen for all types of leprosy patients called Uniform Multidrug Therapy (U-MDT), as a replacement for the present regular multidrug therapy (R-MDT). This U-MDT would consist of treatment of all patients for 6 months with a regimen consisting of three drugs: rifampicin, dapsone and clofazimine. The efficacy of this U-MDT is currently being studied in an open non-controlled treatment trial. Classification of patients is only done on clinical criteria: no skin smears or other lab tests are included. The diagnosis of relapse will rely on clinical diagnosis only. It will therefore not be possible to identify high-risk groups for relapse, such as highly skin smear positive patients.

The objective of our study is to evaluate both the R-MDT and the U-MDT regimens in a randomised trial in order to: