- Building the evidence base: How safe is the global supply chain?
- In most markets, the vast majority of products have never established bioequivalence to the innovator
- India is an increasingly important supplier of drugs for the world. Its products are very cheap, and most live up to basic criteria
Medicine quality does not mean the same thing to everyone. One persons low quality drug is another’s essential life-saver. What is considered a good manufacturing practice is not the same everywhere. GMP has improved over time in United States, so 1981 standards would be unacceptable today and today’s laws may look weak in 2041. What is true through time is also true across the globe.
As my research team sampled drugs from 19 cities in 17 countries and internet pharmacies and assessed them using different methods, it occurred to me again and again that ‘poor quality’ in these samples, let alone in the wider market, is difficult to measure because there is lack of clarity over what constitutes a good product.
"It occurred to me again and again that ‘poor quality’ in these samples, let alone in the wider market, is difficult to measure because there is lack of clarity over what constitutes a good product." In principle and ideally, products should be of the highest quality and, within a category, be bioequivalent to the best product. But in most markets, the vast majority of products have never established bioequivalence to the innovator.
Even those that have done so once, provide no guarantee that quality will be sustained.
Obviously, there are certain criteria that any observer would agree have to be in place, but in the worst markets many products do not meet all of these basic criteria. Some of the most obvious criteria include having the right active ingredients in approximately the right amounts with excipients that allow a product to be reasonably soluble. Yet in the earliest studies my team did of six African cities (approximately 200 samples), we found about 30% of the products failed even these basic criteria (some of these problems could be due to poor storage of products: about 2% looked degraded). 
Since then, quality has improved: from about 900 samples (including the original 200 samples) from 11 African cities about 17% fail. In some locations the improvements have been marked. Lagos in Nigeria showed an improvement from over 30% failure to just under 10% in three years.
In other parts of the world where we’ve tested, failure rates are lower, most well under 10%.  But does that mean that over 90% of these products are good? Not necessarily. Most studies do not measure impurities or degradation which may not be important for drugs like over-the-counter painkillers, but can be critical for others, particularly oncology products.
The reality is that we simply do not know how efficacious most of these drugs really are.
India is an increasingly important supplier of drugs for the world, and especially the poorer parts of the world. Its products are very cheap, and most live up to basic criteria very well (although there do appear to be jurisdictional differences: larger companies from Andra Pradesh and Maharastra consistently produce better quality drugs than smaller companies in other locations, notably Haryana and Uttar Pradesh). We can come back to this if there is interest.
To conclude on the emerging markets, a small percentage of products do not pass basic tests, increasing in Africa, but there is no real knowledge of how these products stack up to western standards.
The rest of my remarks will be confined to drugs bought in the US via online pharmacies, purchased from US and overseas web pharmacies and other web-based drug sellers. Stratifying the sample of five drugs (Celebrex, Lipitor, Nexium, Viagra, Zoloft) by whether the web sites were credentialed (by a government entity or private entity), we found that no web seller credentialed by NABP or pharmacychecker.com sold any products that failed authentication by Raman Spectrometer. This should not be of a surprise; the products we purchased were innovator-brand drugs which were often made in the same country. In some cases authentication was not possible because different versions of the products were substituted (e.g. in Europe Nexium is sold as a tablet, whereas it is a capsule in US), and these products have slightly different spectra. Additionally, generic drugs were occasionally substituted.
Of those sites that were not credentialed, a small percentage (6%) of the products sold failed product authentication. ALL of the product failures came from rogue web sites without a verifiable address, whereas a lot of non-credentialed sites sell real Viagra without prescription at exorbitant prices (even up to $40 a pill, compared with $12-18 in credentialed pharmacies).
While there are lots of interesting problems and possible research within the panoply of non-credentialed sites, such analysis ought to be focused on how to close them down and stop them from selling inappropriate, sometimes bogus, drugs to people without prescriptions.
Analyzing the credentialed sites to learn if there are any real differences between European/Canadian and US pharmacies and the products they sell, on the other hand, could provide valuable insights, and it would establish a dilemma for US policymakers, since while there is no doubt that foreign web sellers can be dangerous, the hundred or so overseas licensed pharmacies, credentialed by pharmacychecker, appear, at least from limited data, to sell safe products.
 Roger Bate, "Generic Compassion: The Challenge of Drugs and International Aid," The New
 Roger Bate et al., Antimalarial Drug Quality in the Most Severely Malarious Parts of Africa-A Six Country Study, http://fightingmalaria.org/pdfs/PLoSAntimalarialDrugStudy.pdf .
 Roger Bate, Lorraine Mooney and Julissa Milligan , 2012. The Danger of Substandard Drugs in Emerging Markets: An Assessment of Basic Product Quality. Pharmacologia, 3: 46-51.
 Roger Bate and Julissa Milligan, "Legal But Deadly," The American, June 30, 2011, http://www.american.com/archive/2011/june/legal-but-deadly.
 Roger Bate et al., A Safe Medicines Chest for the World (London: International Policy Network, May 2010),
www.policynetwork.net/sites/default/files/Safe_Medicines_Chest_2010.pdf (accessed June 30, 2011).
 Bate R, Hess K (2010) Assessing Website Pharmacy Drug Quality: Safer Than You Think? PLoS ONE 5(8): e12199. doi:10.1371/journal.pone.0012199