New evidence of an alternative drug regime to combat latent tuberculosis infection (LTBI) has emerged after a study was undertaken by a team of experts from Christian Medical College (CMC) here, JIPMER in Pondicherry, AIIMS in Delhi and Indian Council of Medical Research.
Dr Pratap Tharyan of CMC said that the study was recently published in the Cochrane Review last week.
Tuberculosis is a common disease caused by a bacterial infection spread through respiratory fluids. Most of those affected have dormant (latent) infections. Only a small percentage of infected people develop an active disease.
According to Pratap, preventing LTBI from developing into active TB, through the use of selective drugs, is an important part of global TB control. The present practice of treatment of using the drug isoniazid (INH) for six to nine months has 60 to 90 per cent protective efficacy, but the treatment period is long. Moreover, liver toxicity is a side effect and completion rates outside trials are around 50 per cent.
“It is imperative to focus on the infection because if the population that harboured the bacteria is not treated, even with a 100 per cent cure rate for those who are ill with TB, we will not be any closer to our goal of eliminating TB,” he pointed out.
The team under the aegis of the Cochrane Review undertook the study to find out whether there are alternatives to treatment using isoniazid monotherapy with reduced treatment period and less side effects.
The drug rifampicin was found to give quiet similar results to isoniazid for 6 months in preventing TB but while exhibiting fewer side effects, he added.
The team analysed data published by 10 trials of various drugs for TB treatment across the world published between 1991-2012, that had enrolled at least 10,000 adults and children, mostly HIV negative, including some with silicosis.
The trials had found out that shortened prophylactic regimens using rifampicin alone have not demonstrated higher rates of active TB when compared to longer regimens with INH.
The new evidence would be of use for governments and healthcare planners to focus on people who are at higher risk of contracting latent TB such as people with kidney disorder, he said.
While countries like India has been battling TB for years through various programmes, LTBI would be an additional burden if not identified and treated early as those suffering from this condition had the greater chance of spreading before they get cured, he added.