Drug-resistant TB

Drug and diagnostics manufacturers have to join fight against drug resistant tuberculosis

 

Medical officer Neisha Mohess, scans a sample of sputum for loading into an automated molecular TB diagnostic machine called GeneXpert.
Medical officer Neisha Mohess, scans a sample of sputum for loading into an automated molecular TB diagnostic machine called GeneXpert. Photo:Jose Cendon

Johannesburg - Alarming new data suggest that the global scope of the drug-resistant tuberculosis (DR-TB) epidemic is much bigger than previously estimated. This requires not only a concerted international effort but also concrete action from global companies such as Cepheid and Pfizer, who keep prices for DR-TB diagnosis and treatment exorbitantly high, says medical humanitarian organisation Doctors without Borders (MSF). MSF calls on Cepheid to lower the cost per cartridge for their diagnostic Xpert MTB/RIFmachine from USD17 to a more affordable USD10 and on Pfizer to lower the prohibitive cost of the drug linezolid for their patients in South Africa.
 
South Africa, challenged with the third highest burden of TB in the world, which is mainly driven by the HIV epidemic, stands to make significant headway with the use of new, faster diagnostic tools, like the Xpert MTB/RIF.The machine is able to test for drug-resistant tuberculosis in just under two hours, as compared with up to several months using other diagnostics. It can also test for smear-positive TB, which is common among people living with HIV. Following the introduction of this laboratory-based test in MSF’s project in rural Eshowe, KwaZulu-Natal last year, the organization has seen a 211 percent increase in TB diagnosis, from 13 to 40 patients a month. About 13.2% of the patients diagnosed with TB were resistant to Rifampicin, one of the best first-line drugs for treating TB.
 
Yet a large scale roll-out of Xpert MTB/RIF, exclusively manufactured by Cepheid, is stymied by the high cost of the diagnostic. Each machine costs USD17,000, and each cartridge costs USD17 in developing countries, including South Africa, the largest purchaser of the machine. For most countries facing massive TB high burdens, many of them in southern Africa, the cost is too prohibitive to effectively roll-out Xpert MTB/RIF. So in order for it to be available to those who need it and thus save more lives, the cost must be drastically reduced.
 
“Because of late diagnosis of drug-resistance, patients are often given the wrong treatment for months, suffering side-effects from drugs that do not help them and robbing them of precious time that would have given them a better chance of cure,” says Dr Jennifer Hughes, who treats DR-TB patients for MSF in Khayelitsha. 
 

GeneXpert was first trialled by MSF (in collaboration with the University of Cape Town, the Cape Town Department of Health
GeneXpert was first trialled by MSF (in collaboration with the University of Cape Town, the Cape Town Department of Health . Photo:Jose Cendon


As more people acquire and are tested for DR-TB, more patients will need treatment, which is still exorbitantly expensive. The course of DR-TB treatment can cost up to USD9,000, versus approximately USD19 for a course of drug-sensitive TB. Linezolid, an antibiotic used byMSF to treat patients, who do not longer respond to any other medication is just one example, where profits take precedence over peoples lives. Often, it is the last resort for patients suffering from DR-TB – this drug, however, is extremely expensive in countries where it is protected under patent, such as South Africa. “In India, generic versions of linezolid are currently available for as little as USD1 to USD2.50 per tablet, while we pay USD90 per pill in South Africa’s private sector, because Pfizer has a patent on this drug. This is outrageous,” says Hughes.

“Wherever we are looking for DR-TB in our projects around the world, we find it in alarming numbers, which suggests that we are only seeing the tip of the iceberg” says Dr GillesVan Cutsem, Medical Coordinator for MSF in South Africa and Lesotho. “As the fight against DR-TB is entering a new round, it is THE time for companies like Cepheid and Pfizer to show they are ready to join in and take responsibility.”

Find out what DR-TB patients around the world have to say about the topic on http://blogs.msf.org/tb/
 
“If I had my way, there would be less medication to take, but stronger,” says XDR-TB patient Phumeza Tisile from Khayelitsha in her video blog

 
NOTES TO EDITORS:
 
TB: Despite existing since antiquity, TB is the second biggest killer globally today, and is now the leading cause of natural death in South Africa. There are more and more cases of TB resistant to first-line drugs normally used to treat it. Currently, an estimated 12 million people are living with TB (reference WHO Global TB Report 2011).
 
DR-TB:Drug-resistant TB (DR-TB) is a form of TB that does not respond to standard treatments using first-line drugs. It is more difficult to treat and treatment takes much longer  - around two years, with highly toxic drugs and severe side effects. In some cases, drug-resistant tuberculosis (DR-TB) develops due to inadequate treatment of drug-sensitive TB. This may occur due to a variety of reasons such as drug supply interruptions, incorrect drug doses or regimens, administration of improper, expired or poor-quality medicines or failure of patients to complete their full course of treatment for any reason, However, the majority of DR-TB cases in South Africa currently are due to transmission of resistant strains from person to person, which is worrying.
 
Cost of treatment for DR-TB: Many DR-TB drugs are only made by a single producer, which means that supply is limited and the price is high. Also countries procure through different mechanisms, which means they don’t benefit from economies of scale. Countries and drug suppliers must address the issue of the high cost of DR-TB treatment, especially given that with the roll-out of new diagnostic tools like the Xpert MTB/RIF machines (GeneXpert) more patients will be requiring treatment.
 
Cost of linezolid: Some drugs used to treat DR-TB are prohibitively expensive because they are under patent, thus blocking generic competition. For example, linezolid, an antibiotic that can be used to treat complicated cases of extensively drug-resistant TB (XDR-TB), costs $90 per 600 mg pill in South Africa’s private sector. MSF’s Khayelitsha project uses linezolid for patients who have very limited further treatment options. For a six-month course of treatment, MSF pays just over $16,000. MSF has repeatedly asked Pfizer, the maker of linezolid, to reduce the price for MSF’s projects in South Africa and Swaziland. Despite continued requests and follow up, MSF has never received a response.
 
Cost of Xpert MTB/RIF machines (GeneXpert): Each machine costs $17,000, and each cartridge costs $17 in developing countries. While, according to Cepheid, the price of cartridges is expected to lower to $10 a piece with an increase in sales, countries with a high burden of TB, such as those in Southern Africa, are simply not able to roll-out the rapid diagnostic due to the high cost—and as such a price reduction is unlikely to occur for some time. Until Xpert MTB/RIF machines and cartridges become more affordable, this potentially revolutionary game-changing diagnostic will not reach those who need it. MSF therefore calls on Cephid to immediately drop the price of the cartridge to $10 per piece; be transparent in its negotiations for large bulk orders and the cost of production of the cartridge; and to ensure that the negotiated price for developing countries is achieved at a country level, with no hidden costs.

Find out more about MSF's work in South Africa.