Private sector TB treatment in Asia: a lot of it, but often sub-optimal

Private sector markets for tuberculosis drugs in some Asian countries are providing enough drugs to treat every new TB case each year – but in many cases patients appear to be receiving drug regimens that are not recommended in international guidelines, according to a major survey published in the journal PLoS One.

Although tuberculosis treatment is largely provided through the public sector in the majority of countries with a high burden of tuberculosis (TB), the coexistence of public and private medical sectors in many Asian countries has led to large-scale dispensing of medicines with very loose regulation.

Until recently public sector TB control programmes were underdeveloped in many Asian countries, leading to large-scale use of private sector diagnosis and treatment.

As governments seek to scale up public sector TB responses with the support of donors it has become clear that greater consistency in treatment approaches between public and private sectors will be an important part of limiting the emergence of multi-drug resistant TB.

For example, public sector programmes have been working towards the adoption of a number of measures designed to limit the emergence of drug resistance, including directly observed treatment during the intensive phase of TB treatment, usually known as DOTS, the use of fixed-dose combinations to improve adherence, and prescription of a very limited number of different drugs based on recent information about drug resistance patterns in each country.

In each case, promoting adoption of these practices in the private sector has proved challenging.

In India one study found that 100 private sector doctors managed to prescribe 80 different TB regimens to their patients, while in the Philippines another study found that 89% of TB prescriptions by private sector providers didn’t match national guidelines.

However, there is little information about the size of private sector TB treatment markets and the drugs prescribed within them that would help national programmes begin to push for changes.

To help in mapping the role of the private sector in TB treatment the Global Alliance for TB Drug Development carried out an international survey of private sector providers with IMS Health, a healthcare market research company, in 10 countries representing 60% of the global TB burden (Bangladesh, China, India, Indonesia, Pakistan, Philippines, Russian Federation, South Africa, Thailand, and Viet Nam).

The most significant finding was the sheer volume of drugs being prescribed in the private sector, and the extent to which total national prescribing in both public and private sectors appeared to exceed the national burden of TB, in some cases by 60 to 80%.

In India, for example, the total volume of TB drugs prescribed for first-line treatment by the private sector in India would treat 117% of the incident TB cases reported in 2008-2009. In Indonesia the volume of prescriptions was equivalent to 116% of incident TB cases, in the Philippines 86% and in Pakistan 65%.

Where did all these drugs go? The researchers suggest that many patients who present for care to public facilities may already have received treatment in the private sector; indeed they note that in India, 86% of patients in one study had first sought care in the private sector.

It is also possible that a large number of cases of TB never get reported properly, despite drug prescription.

However, two other practices may also be contributing to the large volume of prescribing: the tendency of private sector physicians to prescribe TB drugs for longer than recommended in international guidelines, and the use of TB drugs to treat pneumonia.

The study also found that at least one-third of all private sector dosages of first-line TB drugs fall outside of national and international treatment recommendations. No less than 111 different first-line TB drug dosages and combinations were being prescribed in the private sector across ten countries, compared to the 14 deemed necessary by the Stop TB Partnership's Global Drug Facility.

Although a large proportion of first-line TB treatment is being prescribed by the private sector, very few patients with multi-drug resistant TB receive treatment in the private sector, and where MDR-TB treatment is being prescribed, the low volumes of many oral drugs recorded in the survey suggests that it is sub-optimal.

International and national guidelines favour the use of fixed-dose combinations for TB treatment because it helps adherence to medication and ensures that the right doses of drugs are dispensed. While India, Pakistan, Philippines, Bangladesh and South Africa had relatively high volumes of fixed-dose combination prescription in the private sector, greater than 90% of first-line TB prescriptions in the remaining countries still come in the form of loose TB drugs.

Furthermore, some countries appeared to have high levels of prescription of first-line TB drugs at non-standard dosages, which carries a clear risk of either inadequate drugs levels in the case of too-low dosages (most common in China) or side-effects leading to treatment discontinuation in the case of too-high dosages (most common in India). Thirty-five per cent of all first-line TB drugs prescribed across the ten countries were non-standard dosages.

Patients receiving private sector treatment were also paying high prices for TB drugs; on average, almost twice the price at which drugs were supplied to the public sector. An average course of first-line TB treatment in most countries was at least $50, suggesting another reason why so many patients either failed to complete a course of TB treatment, or present to public sector TB clinics after a period of private TB treatment.

"Most countries covered in this study have public-private mix (PPM) programmes for TB care," said Mario Raviglione, Director of the Stop TB Department at the World Health Organization.

"Based on country experiences, these programmes have shown good results in optimising TB management by private care providers. However, the size of the response is not commensurate with the size of the challenge; there is enormous scope to expand these programmes urgently.”

He recommends that private providers following best practices should be supported through accreditation and access to free TB drugs from the public sector, while those not doing so should be regulated.

“Greater government and international support is needed for these efforts and also for improved regulatory oversight and quality assurance of TB drugs. A dual track approach of collaboration and regulation is the logical way forward. We ought to make private providers responsible partners of the public sector in controlling TB and MDR-TB".

Wells WA et al. Size and usage pattern of private TB drug markets in the high burden countries. PLoS One 6 (5): e18964, 2011. (View full text of the article free of charge here).