World TB Day 2021: The Challenge of Drug Resistant Tuberculosis

Although tuberculosis is considered a disease of the past, there has been a resurgence, especially in developing countries across the world. According to estimates by the World Health Organization, there are over 10 million new cases in the world. It also added that the epidemic is larger than previously estimated, owing to data from India. 60 percent of TB cases are concentrated to six countries. India leads the pack, closely followed by Indonesia and China, while Nigeria, Pakistan are not far behind.

Drug-resistant tuberculosis is particularly hard to treat using medicines that are currently available in the market. Since the drug resistant variants come in different forms – extensively drug resistant and multi drug resistant – patients who are infected are resistant to at least four of the main anti-TB drugs. This is complicated by the fact that rifampicin and isoniazid, two of the most effective anti-TB drugs, have become both ineffective and toxic. So doctors are forced to prescribe less effective drugs that have to be taken over a longer period. For both the variants, patients have to take a lot of pills and daily injections for two years. However, even with this rigorous regimen, the cure rate hover around 60 percent, even at the best centers.

While the standard course of TB medication costs a little over a 1000 rupees, the treatment cost for multi drug resistant TB can go up to 1,50,000 rupees for one year, which is usually the minimum duration of the treatment. The government also does not offer a treatment programme for TB. Although the TB control programme DOTS, which was aimed at providing a standardized drug treatment to TB patients, reached over 600 districts, it was not entirely foolproof. There were considerable delays in diagnosing affected patients and prescribing the right course of medication, not to mention ensuring patients adhered to their regimens, which ended up perpetuating the cycle of transmission. Sticking to a one size fits all approach only amplified the drug resistance.

The harsh reality of the situation is that there have been a high number of TB and drug resistant TB cases in India because of policy shortcomings. Initially, public health officials turned a blind eye to drug resistant patients, and the numbers continued to rise. When the DOTS programme was reassessed and DOTS plus was rolled out, it posed its own unique set of challenges. The drugs that were needed were expensive and often difficult to obtain.

Access to more Promising Drugs

After four decades of dormancy in tuberculosis research, two effective and less toxic medicines were finally released in 2012 – Bedaquiline and Delaminid. Bedaquline blocks the mechanisms used by the TB bacteria to produce energy, effectively killing it in the process. Thousands of patients across the country are in need of these medicines. Although the government announced that patients will get universal access to Bedaquiline, a lot of them are still denied access. According to authorities, its use has to be carefully monitored since it is still in the trial phase. This is complicated by the fact that it is expensive and we are yet to scale up affordability and access.

More recently, a three drug regimen, consisting of Bedaquline, Pretomanid, and Linezolid, showed a 90 percent favorable outcome in treating drug-resistant tuberculosis. The results of the study, which was published in The New England Journal of Medicine, comes as a ray of hope for people suffering from drug-resistant TB. This is no small feat, as Pretomanid is the only other drug developed for TB in over half a century.

It is difficult to tell how soon patients in India will gain access to these drugs. At present, there are only a handful of government hospitals where Bedaquiline is administered, and presenting with a form of drug related TB does not guarantee access. According to government regulations, patients cannot access the drug unless they are residents of the state where it is administered. It is disheartening to see that only a fraction of the people suffering from the disease get the treatment they need. We hope that there is a change in policy that increases access and affordability so that patients get the treatment they need, and TB truly becomes a disease of the past.

Credits: Dr Shuchin Bajaj, Founder Director, Ujala Cygnus Groups of Hospitals