IIT-Bombay study gives hope to resistant-TB patients

MUMBAI: In what can bring hope for drug-resistant TB patients, a study conducted by IIT-Bombay has shown that an anti-TB drug - rifampicin - used in combination with other drugs, can significantly improve medicinal efficacy. Rifampicin is one of the two main powerful drugs that TB bacteria are resistant to in multiple-drug resistant TB, or MDR TB cases.

In the study published in the journal Frontiers in Microbiology, Sarika Mehra, professor from IIT-B's chemical engineering department, and her PhD student Yesha Patel, showed how the effectiveness of rifampicin can be improved by delivering it with another drug called cumene hydroperoxide (CHP). The researchers claimed that the antibiotic used in combination with other drugs could also reduce its side effects.

Another study using the same mechanism with FDA-approved drugs is under review for publication. Once published, it can pave way for clinical trials and thereafter, the method can be put to use in TB treatment.

CHP, an oxidising agent, was used by the researchers only to prove the mechanism of drugs working in synergy. The researchers tested their combination of drugs on two species of TB bacteria. They subjected the bacteria to various combinations of the antibiotic rifampicin and CHP, in different doses. They found that if used in combination, the rifampicin dose required was 16 times less than its individual dose. Dosage reduction would imply fewer side effects.

"The idea was to make use of a compound which may not have antibiotic properties but can enhance the efficacy of anti-TB drugs. In the second study, we made use of another drug which had similar properties and is also FDA-approved. It would be easier to take it forward for clinical trials," said Mehra.

Drug-resistant TB is caused when bacteria evolve mechanisms to survive due to irregular and improper use of antibiotics.

Treatment for MDR-TB involves a two-year long regimen and patients are often left with severe side effects. In most countries, the rate of successful treatment is only about 50%. India contributes largely to the overall cases of drug-resistant TB.

"Many bacteria are developing resistance to common antibiotics faster than the number of effective drugs being discovered to fight them. The need of the hour is, therefore, not just a new drug, but also a new method of treatment," said Mehra. Explaining the way forward, Mehra said the plan is to conduct research on actual strains of mycobacterium TB in collaboration with a lab.