New TB drug regimen may shorten treatment

Researchers have designed a new tuberculosis drug regimen that may significantly shorten and simplify the treatment of drug-sensitive and drug-resistant TB.

The drug regimen eliminated more bacteria from sputum than standard therapy and did so at a faster rate, according to data from a phase 2b clinical trial published in The Lancet journal.

These results are published just as the global phase 3 clinical trial, designed to bring this regimen through the last stage of testing, has begun, 'medicalxpress.Com' reported.

PaMZ is a three-drug regimen comprised of two candidate drugs that are not yet licensed for use against TB: pretomanid (Pa), formerly known as PA-824, and moxifloxacin (M), and one antibiotic, pyrazinamide (Z), which is approved for use in TB treatment.
 

The therapy is intended for those patients whose TB infections are sensitive to the three drugs, including people with drug-sensitive and multi-drug-resistant TB (MDR-TB).

"The results of this trial show the potential for the PaMZ regimen to improve treatment for tuberculosis," said Rod Dawson, head of the Centre for TB Research Innovation at the University of Cape Town, South Africa.

"Especially noted is the fact that PaMZ may have a unique application as a potentially shorter, injection-free regimen for a select sub-group of patients with MDR-TB," said Dawson, lead author of the paper.

The Phase 2b trial tested PaMZ in an eight-week study that enrolled more than 200 patients and took place at eight sites in South Africa and Tanzania.

Nearly twice (71 per cent) as many TB patients treated with PaMZ had no TB in their sputum when cultured at the end of the 2-month course of the trial compared to patients treated with standard therapy (38 per cent).

Patients in the arm of the trial that tested the effectiveness of PaMZ on MDR-TB responded similarly to those with drug-sensitive TB. However, the study group for MDR-TB was small.