Report: GeneXpert TB diagnostics take off in low-resource countries
As of the end of the first quarter of 2012, nearly 864,000 GeneXpert MTB/RIF rapid tuberculosis (TB) diagnostic cartridges had been procured under manufacturer Cephied’s concessional pricing mechanism.
The information was part of a the three-page report released in May by the Stop TB Department of the World Health Organization (WHO), giving an update on the implementation and roll-out of the MTB/RIF diagnostic that can also detect strains resistant to rifampicin, a first-line drug used to treat active TB infection.
Xpert MTB/RIF implementers, technical partners and donors joined together in France in April to discuss roll out during the 4th Global Laboratory Initiative Partners meeting, the outcomes of which are discussed in the report. While implementers relayed that users were overall pleased with the GeneXpert MTB/RIF – which was endorsed by the WHO in December of 2010 – there were repeated concerns raised about the obstacle the price of the technology plays, especially in terms of accelerated and sustainable roll-out, in both low- and middle-income countries. The individual testing cartridges currently cost $16.86, while the GeneXpert machines cost upwards of $17,500, depending on the number of modules in the machine. (Machines come in one, two, four, or 16-module configurations).
Cepheid has noted that as demand continues to rise, the cartridge price will continue to drop to the floor price of $10.68 by 2014, but some advocates fear that price is still too high. The report notes that pricing negotiations are ongoing between Cepheid and major buyers and donors, but also mentions the need to make the technology more accessible to the large private sector in many high-burden countries. For example, in India the majority of those seeking testing and treatment for TB seek out care in the private sector, where they often do not receive quality care.
“The establishment of collaborations between private providers and national TB control programs would be mutually beneficial, allowing for private providers to access concessional prices and for national TB control programs to ensure patients detected in the private sector are duly reported and subsequently registered for appropriate treatment,” according to the report.
Despite the price barriers, the report shows (utilizing data from the Foundation for Innovative Diagnostics) the cumulative number of GeneXpert modules and MTB/RIF cartridges procured under concessional pricing continues to grow – with nearly 3,000 modules placed by the end of the first quarter of 2012 (a total of 611 GeneXpert machines), whereas only 42 had been placed at the end of the fourth quarter of 2010 (see chart right). More than half of the cartridges (478,980) have been procured for use in South Africa alone, followed by Kenya (34,310), India (25,640), Pakistan (22,440) and Zimbabwe (21,570) rounding out the top five. The WHO continues to monitor global cartridge and module roll-out.
The report also highlights reports of errors and invalid results during the initial phase of GeneXpert MTB/RIF implementation in a relatively small but significant number of sites, with recurring errors at some sites linked to errors in specimen collection and sample preparation, and faulty modules and cartridges. Performance does seem to improve over time at most sites. There have also been challenges in ensuring the availability of appropriate treatment for individuals who test positive for drug-resistant tuberculosis.
Other recommendations in the report include:
- Continued innovation to allow the use of the GeneXpert MTB/RIF in more settings at levels closer to the point of care, where lack of reliable electricity and high temperatures may otherwise prevent reliable use of the technology;
- Implementation of electronic information management systems and mobile technology initiatives to facilitate stronger links between diagnosis and follow up care;
- Financial mechanism innovation by donors and buyers to perpetuate a decrease in prices with higher volumes of cartridges procured; and
- Innovation to “close the gap” between diagnostics and treatment, or scaling up treatment to match diagnostic capacity, in particular to ensure proper treatment of those diagnosed with rifamipicin-resistant TB.
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