Fighting a losing battle?

MSF shows drug-resistant tuberculosis treatment succeeds in barely half of all patients, and warns of the emergency where HIV is rampant

The international medical organisation Médecins Sans Frontières (MSF) today released statistics showing that even under optimised conditions, treatment will succeed in barely more than half of patients with multi-drug resistant (MDR) Tuberculosis (TB). As insufficient research and development on new drugs and diagnostics has left health staff without the right tools to treat the disease, some patients will go on to develop extensively drug-resistant (XDR) TB regardless of the quality of care they are offered. The situation is particularly alarming when treating people co-infected with TB and HIV.

"When resistance emerges to the major TB drugs, we're forced to go back to using older less effective ones", said Dr. Jessica Adam, a doctor in MSF's programme in Uzbekistan. "This means a much longer, much more expensive treatment course that can cost up to US$15,000, and especially relying on drugs that are toxic: the side effects are simply horrible."

Since 1999, MSF has invested considerable resources, and provided rigorous support to treat 570 patients with MDR TB in Armenia, Abkhazia, Georgia, Cambodia, Kenya, Thailand, Uganda, and Uzbekistan. Despite these efforts, only 55% of these patients completed the 18-24 month course of treatment. The remaining 45% died, did not improve on treatment, or defaulted because of side effects, isolation, and other difficulties in tolerating the treatment.

Diagnosing MDR-TB is also extremely difficult. Most resource-poor settings do not have access to the necessary sophisticated equipment. But even in the best of settings that do, it can take up to eight weeks to get a result. In patients co-infected with HIV who are already sick, such delays can mean the difference between life and death.

"In places where we see a lot of HIV/AIDS, the risk of MDR-TB spreading like wildfire is a terrifying, but all too likely prospect," said Dr. Liesbet Ohler from MSF's programme in Mathare, a slum near Nairobi. "Treating MDR-TB and HIV simultaneously is incredibly frustrating because of drug interactions and the potential for many strong side effects, let alone the number of pills patients have to take everyday. With the tools we have today, we're fighting a losing battle."

Last year's XDR epidemic in South Africa sparked international concern about the extent of the crisis and the urgency of finding solutions. Now, concrete actions need to be taken. The World Health Organisation (WHO) needs to take the lead to develop new strategies against the disease.

Despite the urgency of the situation, current research efforts are not keeping pace with the need for better tests, drugs and vaccines. An analysis conducted by MSF of the TB research and development pipeline found that none of the compounds under development today will be able deliver the drastically shorter treatment that is needed to curb the disease. Similarly, the diagnostics under development will not be simple enough to use in resource-limited settings and will not reliably detect the disease. There is a critical funding gap for research and development for TB with around $900 million needed annually but only $206 million being invested.

"MDR TB, and now XDR TB are the tip of an iceberg of failing strategies to curb TB. We desperately need new tools and we need them now - we cannot just sit and wait," said Dr. Tido von Schoen-Angerer, Director of MSF's Campaign for Access to Essential Medicines. "There is no quick ready-made solution, but that is not an excuse not to act. One important step is to have all TB drugs in development tested in trials with MDR patients: this would be a quicker way to see whether new compounds are efficacious for patients with regular TB and give those with MDR a chance for a better treatment. At the moment, only one company has stated that it is planning to conduct an MDR trial while others sit on the fence. WHO needs ensure that these trials will happen".

MSF is currently treating over 20,000 people with TB in more than 40 countries.