E-DRUG: Counterfeit and substandard ARVs in Africa? (2)
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Hi
there was a very good publication by WHO in 2007 that was a survey of the quality of antiretroviral medicines circulating in selected African countries
available at
http://apps.who.int/medicinedocs/en/m/abstract/Js14230e/
Here is the abstract
Abstract
Background: Provision of antiretroviral therapy has expanded in Sub-Saharan Africa and quality assurance of antiretrovirals is of crucial importance for the success of treatment programmes. Therefore WHO, in co-operation with national authorities, organized a quality survey of antiretrovirals in selected African countries. Methods: The survey was performed in Cameroon, the Democratic Republic of Congo, Kenya, Nigeria, United Republic of Tanzania, Uganda and Zambia.
Country teams made up of WHO country officers and national authority representatives collected samples at public and private sector antiretroviral procurement organizations and treatment centres around the capital cities. Samples included monocomponent products of didanosine, efavirenz, lamivudine, nevirapine, stavudine and zidovudine, and fixed-dose combinations of lamivudine/zidovudine, stavudine/lamivudine, stavudine/lamivudine/nevirapine.
All samples were tested by the Official Medicines Control Laboratory of Switzerland, Swissmedic, for appearance, labelling, identity, related substances, and content of each active ingredient. In addition, capsules and tablets were tested for uniformity of mass and either dissolution or disintegration; oral solutions were tested for pH if appropriate. Methods of the International Pharmacopoeia, United States Pharmacopoeia, Indian Pharmacopoeia or manufacturers' methods with method transfer were used as appropriate.
Sampling and testing were carried out over a period of six months from 13 June to 15 December 2005.
Findings: None of the antiretrovirals sampled had any critical quality deficiencies which would pose a serious risk to patients. In 394 samples collected, the overall failure rate was 1.8%. One sample contained a broken tablet and tablets with chipped coating. Two samples were insufficiently labelled on the immediate packaging. The content of active ingredient of one sample exceeded the upper limit. One of 163 samples tested for disintegration failed to disintegrate completely within 30 minutes, and two
of 153 samples tested for dissolution showed lower results than required. Fifty-three percent of sampled products were WHO-prequalified.
Information on registration by National Drug Regulatory Authorities was available for 285 products; of these, 84% were registered. Products not registered at the time of sampling were found in three countries, mostly at private sector facilities, and constituted 12% of the total of 394 sampled products.
Conclusions: The generally good quality and safety of products sampled indicate the positive effect of common efforts of National Drug Regulatory Authorities, WHO and other organizations involved in prequalification and purchase policies. Market control was still incomplete in at least three countries. Since the survey was limited to official distribution points and treatment centres around the capital cities, these results cannot be generalized to the entire territories of the countries surveyed.
Other surveys of the quality of antimalarials and anti TB medicines were also done at the same time and did not show the same good results. Malaria medicines had a 28.5% failure rate and TB medicines had 11.3% failures with zero failure rates among WHO prequalified suppliers.
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I am not aware of more recent comprehensive survey results which used robust assay methods. There have been studies reported by the American Enterprise Institute which used screening methods only and did not collect representative samples. These results have been reported at
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2492979.
These are for antibiotics and anti TB drugs.
So if you are planning to do such a study do go ahead as we need such data. But make sure that you draw a representative sample and when you test ensure that you test using robust methods. You may want to use rapid screening tests initially but for all products that fail these initial tests you should do pharmacopeial standard tests.
Do report any failures to the national regulatory authorities and to the WHO Drug Alert system.
See http://www.who.int/medicines/publications/drugalerts/en/ .
Richard
Richard Laing
Professor International Health
Boston University School of Public Health,
801 Massachusetts Avenue Boston MA 02118
Tel 617 414 1445 (Office) 617 435 7860 (Mobile)
E mail richardl@bu.edu