An analysis of the active ingredients of common cardiovascular drugs—antihypertensives, an anticoagulant, and a statin—that were purchased in street markets and pharmacies in 10 sub-Saharan countries found that one in six drugs (16.3%) was of “low quality”.
Moreover, if the cardiovascular drugs were purchased from street markets and originated in Asia, “you have an almost one in two chance of low quality, which is really a disaster,” said Dr Xavier Jouven (INSERM, Paris, France), presenting these findings at an oral poster session at the European Society of Cardiology (ESC) 2015 Congress.
According to Jouven, although many publications have reported on the quality of drugs for cancer, HIV, malaria, and tuberculosis, “this is the first time that an analysis of the quality of cardiovascular drugs in Africa has been performed . . . and we discovered that the level of low-quality drugs is really high”.
“The growing menace of counterfeit medicines poses a serious threat to patient safety and public health,” first author Dr Marie Antignac (Hôpital Saint-Antoine, Paris) and colleagues write. “Our results suggest the need for continued monitoring strategies for assessing drug quality in developing countries.”
Comoderator at the poster session, Dr Sripal Bangalore (New York University School of Medicine, New York), commented that this study, presented as two posters, identifies that “we are not only facing a problem with drug adherence, but you also have this problem where [patients] might be taking a drug but the quality is low.”
The study showed that generic drugs were more likely to be of poor quality, he noted. This is something that physicians may worry about. “Usually after I put in a stent, I’m a little bit nervous about giving a generic drug at that time,” he said. It would be interesting to repeat this study in the United States and Europe to see the quality of generic and brand drugs, he suggested. Jouven agreed, but added, “I expect that the numbers would not be so high (I hope!).”
Counterfeit Cardiac Drugs in Africa
“Studies on the quality of drugs in Africa have focused exclusively on antimicrobials, whereas leading causes of morbidity and mortality in low- and middle-income countries are shifting from infectious to noncommunicable causes such as cardiac disease,” Antignac and colleagues write.
Jouven explained that while working in Africa to help physicians implant pacemakers, he noticed that the quality of cardiovascular drugs was a big public-health problem there. He works with a network of 15 African countries, and 10 countries agreed to participate in the current study.
Between 2012 and 2014 the researchers collected 1530 samples of seven drugs (acenocoumarol, simvastatin, amlodipine, atenolol, captopril, furosemide, and hydrochlorothiazide).
The drugs were purchased in 32 licensed pharmacies (n=880) and 19 unlicensed street markets (n=650) in Senegal, Burkina Faso, Benin, Ivory Coast, Togo, Niger, Democratic Republic of Congo, Congo, Mauritania, and Guinea.
The researchers identified the active ingredients in the drug samples using a validated reverse-phase liquid chromatography with tandem mass spectrometry method in a certified public laboratory in France.
The samples were classed into three quality categories, based on percentage of the expected concentration of the active ingredient: good quality (>95%), low quality (85% to <95%), and very low quality (<85%).
About a quarter of the samples of amlodipine (28.5%) and captopril (25.5%) were of poor quality (low or very low quality).
Quality of Seven Cardiovascular Drugs Purchased in 10 African Countries
|Drug||Good quality, n (%)||Low quality, n (%)||Very low quality, n (%)||Total|
|Amlodipine||218 (71.5)||84 (27.5)||3 (1)||305|
|Atenolol||208 (84.9)||37 (15.1)||245|
|Captopril||175 (74.5)||39 (16.6)||21 (8.9)||235|
|Furosemide||210 (87.5)||30 (12.5)||240|
|Hydrochlorothiazide||157 (98.1)||3 (1.9)||160|
|Simvastatin||148 (82.2)||32 (17.8)||180|
|Total||1218 (83.7)||225 (14.7)||24 (1.6)||1530|
The percentage of poor-quality drugs was higher in unlicensed street markets vs licensed pharmacies, but this was not significant (19.8% vs 13.6%; P=0.29).
Generic drugs were 10 times more likely than brand-name drugs to be of poor quality (23.3% of 1000 generic drugs vs 2.3% of 475 brand-name drugs; P<0.001).
Drugs manufactured in Asia (35.3% of 235 drugs) were more likely to be of poor quality than drugs manufactured in Africa (19.4% of 170 drugs) or in Europe (8.7% of 970 drugs).
The country of origin was not indicated on the label of 155 drugs, and it was not clear if 55 drugs were generic or brand-name drugs. Drugs that were manufactured in Asia and sold in unlicensed street markets had the highest rate of poor quality (43/95, or 45%).
Patients get a prescription from their doctor and then try to buy the drug where it is less expensive, Jouven explained. Thus, depending on where the patient buys a cardiac drug such as a beta-blocker or an anticoagulant, they may be receiving a much lower dose than they think they are taking.
“Hypertension is the most important killer in Africa now. That’s a real important issue,” he said. Countries would need to have stricter laws against importing and selling poor-quality drugs, and further studies might help draw more attention to this.
Antignac M, Diop IB, Do B, et al. First quality assessment of cardiovascular drugs in 10 Sub-Saharan African countries: The Seven Study. European Society of Cardiology 2015 Congress; August 31, 2015; London, UK. Abstract 3134.
Antignac M, Diop IB, Bernard M, et al. Quality of cardiovascular drugs in street markets and pharmacies in 10 Sub-Saharan African countries: The Seven Study. European Society of Cardiology 2015 Congress; August 31, 2015; London, UK. Abstract 3135.