Recently released research bolsters the case for more effective, less toxic and shorter treatment regimens for drug-resistant tuberculosis, offering hope for patients suffering from a disease that is notoriously difficult to treat. The Wall Street Journal reports that the three separate studies are among several that TB researchers have under way to develop new drug combinations to replace current treatments that last as long as two years, involve up to 15,000 pills, and can cause deafness, renal failure and other debilitating effects. Many patients are never cured.
Findings in two of the studies suggest that the bedaquiline and delamanid, the first new drugs for TB in about 50 years, should be made more widely available, TB experts say. “There is no question that these drugs should be used more widely,” said Paul Farmer, chief strategist and co-founder of Partners in Health, which is part of a consortium conducting one of the new studies being presented at the 48th Union World Conference on Lung Health in Guadalajara, Mexico.
The report says the new drugs have been given to fewer than 11,000 patients since bedaquiline was approved by the US Food and Drug Administration (FDA) nearly five years ago. That compares with an estimated 580,000 people who are infected with drug-resistant TB every year.
Earlier studies on the new drugs, conducted on small numbers of patients, left open the question of whether the drugs would be safe when delivered in larger numbers. Some patients in these studies developed a condition considered to be a marker for cardiac problems such as heart arrhythmias and possible sudden death.
The drugs were approved conditionally by some regulators such as the FDA. But the World Health Organisation (WHO) urged caution and recommended they be used only for patients who couldn’t be treated with certain second-line drugs.
The report says in one of the new studies, researchers examined 356 patients in 15 countries who had severe forms of drug-resistant TB and were started on new drug regimens with bedaquiline or delamanid or both. They found that 82% of the patients responded to the new treatment within six months, a substantial number given that many had already tried and had no success with regimens of older drugs, said Carole Mitnick, associate professor of global health and social medicine at Harvard Medical School and Partners in Health’s director of research for the end-TB project, the consortium conducting the study. There were no cardiac events, she said.
The consortium is also testing the new drugs in new, shorter regimens. The endTB consortium aims to expand the market for bedaquiline and delamanid with $60m in funding through 2019 by Unitaid, an organisation that invests in making drugs and diagnostics for HIV/Aids, tuberculosis and malaria accessible. The consortium includes PIH, Doctors Without Borders, and Interactive Research & Development, a global health-delivery and research group.
The report says in the second study, the maker of delamanid, Otsuka Pharmaceutical, had similar results. The study found that 83.6% of patients on an existing drug regimen to which delamanid was added responded to treatment within six months, compared with 78.2% who were on the regimen without delamanid. The company says that patients on delamanid responded to treatment six to 13 days quicker. More than three-quarters of patients in both groups were cured, the company said. No cardiac events were reported.
The WHO will review the data on delamanid in the next couple of weeks, said Karin Weyer, coordinator of diagnostics, laboratories and drug resistance for the WHO’s Global TB Programme.
A third trial presented at the lung conference found a nine-month regimen of existing drugs was about as effective as a two-year regimen in patients who don’t have complicated drug resistance. Trial investigators noted that it is less costly and easier on patients. The WHO began recommending the shorter regimen many drug-resistant patients last year, and Weyer said the new data provide reassurance for the WHO’s policy. The report says the study was led by the International Union Against Tuberculosis and Lung Disease.
No abstracts available
[link url="https://www.wsj.com/article_email/new-treatments-for-drug-resistant-tb-get-a-boost-1507892402-lMyQjAxMTA3MjExMzExNTM4Wj/"]The Wall Street Journal report[/link]