A systematic review of counterfeit and substandard medicines in field quality surveys

Figures & data

Figure 1 Flow chart for articles inclusion in systematic review.

Table 1 Research articles reporting both counterfeit and substandard medicines

Reference	Country	Medicine	Sample size	Authenticate source	Visual analysis	Chemical analysis	Physical analysis	Results	Type of substandard/spurious/ falsely labeled/falsified/ counterfeit medicine problem
Bate et al^Citation30	17 countries from all continents	Antituberculosis isoniazid and rifampicin	713	NR	Package	TLC	Disintegration	65/713(9.1%) substandard; 18/713 (2.5%) counterfeit	Low API%; no API or suspicious packaging
Stanton et al^Citation31	Ghana	Ergometrine, oxytocin	101	NR	NR	Performed by local food and drug administrations	NR	92/101 (91%) substandard; 1 /101 (1 %) counterfeit	Low or high API%, 2 expired; no API
Baratta et al^Citation32	15 different countries	Various therapeutic classes and formulations	196	NR	NR	UV and some with HPLC	Uniformity of content, mass, disintegration, friability and hardness tests	101/196 (52%) substandard; 4/196 (2%) counterfeit	Various failures mostly physical; no API
Nair et al^Citation33	Papua New Guinea	Antimalarial amodiaquine and antibiotic amoxicillin	14	Internet search and e-mail contact manufacturer	Package and label inspection	TLC and HPLC	Weight variation, content uniformity, dissolution	11/14 (79%) substandard; 3/14(11%) counterfeit	Poor content uniformity, fails assay and inappropriate packaging; no API, no manufacturer address, and distributor does not exist
Ali et al^Citation34	Nigeria	Antimalarial ACT	6	NR	Package inspection	UV	NR	3/6 (50%) substandard; 2/6 (33%) counterfeit	Low API%; missing manufacturer details on package, and no expiry date
Khan et al^Citation35	Cambodia	Albendazole, mebendazole, and metronidazole	203	Contact with manufacturer and authorities	Package inspection	HPLC	Disintegration and weight measurement	2% substandard; 4% counterfeit	Failed disintegration; failed authenticity with manufacturer or authorities
Ochekpe et al^Citation36	Nigeria	Antimalarial artemisinin combination therapies	70	NR	Package inspection Minilab® (Global Pharma Health Fund eV, Giessen, Germany)	TLC	Disintegration	27/70 (38%) substandard; 4/70 (6%) counterfeit	Low API%; no API and fake packaging
Bate et al^Citation37	India	Antimalarial, antibiotic, and anti mycobacterial	541	NR	NR	TLC	Disintegration	46/541 (8.5%) substandard; 1 1/541 (2%) counterfeit	Low API% and disintegration failure; no API
Onwujekwe et al^Citation38	Nigeria	Antimalarial	225	NR	NR	HPLC	Dissolution	60/225 (37%) substandard or counterfeit	Less API% or wrong API
Risha et al^Citation39	Tanzania	Antimalarial, antibiotic, and antiretroviral	1,257	NR	Package inspection Minilab^®	Color reaction and TLC	Disintegration test and dissolution	46/1,257 (3.6%) substandard; 5/1,257(0.4%) counterfeit	Dissolution failure mostly; NR
Tipke et al^Citation40	Burkina Faso	Antimalarial	77	Internet search was for manufacturers	Package inspection Minilab^®	Color reaction and TLC	Disintegration	32/77 (42%) substandard; 1/77 (1.2%) counterfeit	Failed visual inspection, low API%, and failure of dissolution test; no API
Bate et al^Citation41	Six African countries	Antimalarial	210	NR	Package inspection	TLC	Dissolution	35% (73/210) substandard; 7/210 (3%) counterfeit	Low API% and dissolution failure; missing manufacturing, and/or expiry date on the package
Pouillot et al^Citation42	Cameroon and Niger	Antimalarial, antibiotic, and antihelmintic	153	NR	Basic package inspection	HPLC and UV	Average weight and uniformity of mass, disintegration, dissolution	66/153 (43%) substandard; 5/153 (3%) counterfeit	Nonconforming to API% and physical tests; no API
Ofori- Kwakye et al^Citation43	Ghana	Antimalarial artesunate	17	NR	Basic package inspection	Colorimetric and spectrometry	Uniformity of weight, breaking strength, friability, and rate of disintegration	11/17 (65%) substandard; 1/17 (6%) counterfeit	Failed content uniformity test; manufacturer address missing
Atemnkeng et al^Citation44	Congo	Antimalarial	28	NR	Package inspection	UV, TLC, and HPLC-UV	NR	4/28 (14%) substandard; 13/28 (46%) counterfeit	Low and high API%; no API, no manufacturer name, and no trade name
Gaudiano et al^Citation45	Congo, Burundi, and Angola	Antimalarial	30	NR	Package and label	HPLC	Uniformity of mass, disintegration, and dissolution	17/30 (57%) substandard; 1/30 (3%) counterfeit; 1/30 (3%) diverted	Low API% and physical test failures; no API; humanitarian medicine
Atemnkeng et al^Citation46	Kenya and Congo	Antimalarial artemisinin- derivative drugs	24	Checked source of some companies	Check for illegal prints only	HPLC-UV	NR	9/24 (38%) substandard; 3/24 (12.5%) counterfeit	Low and high API%; nonexistent manufacturer
Syhakhang et al^Citation47	Laos (two studies in 1997 and 1999)	Antibiotic, antimalarial, and aspirin	666	NR	NR	HPLC, titration, and UV	Weight variation and disintegration	46% and 22% substandard in 1997 and 1999; 1 % counterfeit	Low or high API% and failed weight variation; no API
Basco^Citation48	Cameroon	Antimalarial	284	NR	NR	Color test and TLC	NR	53/284 (18%) substandard; 59/284 (20%) counterfeit	Low API%; no API
Dondorp et al^Citation49	Thailand, Vietnam, Cambodia, Lao People’s Democratic Republic, and Myanmar	Antimalarial artesunate derivatives and mefloquine	303	NR	Package analysis of holograms	Color test and HPLC	NR	99/303 (33%) counterfeit; 4/303 (1%) substandard	No or trace API, and all were artesunate; substandard API% and all were mefloquine
Prazuck et al^Citation50	Myanmar	Antibiotics	21	NR	NR	UV, TLC, and titrimetry	NR	10/21 (48%) substandard; 3/21 (14%) counterfeit	Low, high API% and expired medicines; wrong API and no expiry date on package
Taylor et al^Citation51	Nigeria	Antimalarial, antibiotic, antituberculosis, antifungal	581	NR	Basic package information on origin	HPLC	NR	279/581 (48%) substandard; 43/581 (7%) counterfeit	Low API%; no API and no origin country on package
Stenson et al^Citation52	Laos	Antibiotics ampicillin and tetracycline	366	NR	Basic visual analysis	Color test, TLC, HPLC, UV, and titration	Measurement of weight variation	42/366 (11.5%) substandard 12/366 (3.3%) counterfeit	Low or high API% and weight variation; no API
Shakoor et al^Citation53	Nigeria and Thailand	Antimalarial and antibiotics	96	NR	Package inspection for obvious errors	HPLC	NR	36% from Nigeria and 40% from Thailand substandard; 6/96 (6%) counterfeit	Low or high API% and signs of decomposition; no API

Abbreviations: API, active pharmaceutical ingredient; NR, not reported; TLC, thin layer chromatography; HPLC, high-performance liquid chromatography; UV, ultraviolet; ACT, artemisinin combination therapies.

Table 2 Research articles reporting counterfeit medicines only

Reference	Country	Medicine(s)	Sample size	Authenticate source	Visual analysis	Chemical analysis	Physical analysis	Results	Type of substandard/spurious/ falsely labeled/falsified/ counterfeit medicine problem
Dorlo et al^Citation54	Bangladesh	Miltefosine	2	NR	Package inspection	Liquid chromatography- mass spectrometry, Fourier transform infrared spectroscopy, near-infrared spectroscopy, colorimetric test	NR	Both (100%) failed all tests and are counterfeit	No API
Newton et al^Citation12	Multiple countries in Africa	Antimalarial	59	Contact manufacturer	Package inspection	HPLC, mass spectroscopy, pollen analysis, X-ray diffraction	NR	Only case reports of counterfeits and do not allow for percentage estimation	Wrong API, nonexistent manufacturer, no API, hologram different from genuine package, and wrong name on packaging or leaflet
Sengaloundeth et al^Citation55	Laos	Antimalarial artesunate	30	NR	Package analysis	Colorimetric tests, HPLC, mass spectroscopy, pollen analysis, X-ray diffraction	NR	88% failure and counterfeit	No or wrong API, wrong spelling of “tablet” on package and unusual interval between manufacturing date and expiry date of 9 years
Newton et al^Citation56	Vietnam, Cambodia Myanmar, Laos, and Thailand	Antimalarial artesunate	391	Contact with one company to authenticate batch numbers	Package analysis including holograms	Colorimetric, HPLC, mass spectrometry	NR	195/391 (50%) counterfeit	Fake hologram, wrong spelling on packaging, use of different font, failure of authentication when manufacturer was contacted, and no API
Newton et al^Citation57	Myanmar, Cambodia, Vietnam, Laos, and western Thailand	Antimalarial artesunate	104	NR	Package inspection and holograms, printing, and bar codes	Color reaction test	Tablet weight, size, and color	Overall, 38% are counterfeit found in all countries	No API, different taste of tablets, heavier weight of tablets, and different packaging and holograms compared with genuine

Abbreviations: API, active pharmaceutical ingredient; NR, not reported; HPLC, high-performance liquid chromatography.

Table 3 Study with no report of substandard or counterfeit medicines

Reference	Country	Medicine	Sample size	Authenticate source	Visual analysis	Chemical analysis	Physical analysis	Results
Said et al^Citation58	Malaysia	Paracetamol	16	NR	NR	Near-infrared spectroscopy	NR	All samples passed but with variable quality

Abbreviation: NR, not reported.

Table 4 Research articles reporting only substandard medicines

Reference	Country	Medicine	Sample size	Authenticate source	Visual analysis	Chemical analysis	Physical analysis	Results	Type of substandard/spurious/ falsely labeled/falsified/ counterfeit medicine problem
Haruna et al^Citation59	Nigeria	Anti hypertensive methyldopa	4	NR	NR	Nonaqueous titration	NR	1/4 (25%) substandard	Low API%
Audu et al^Citation60	Congo	Antihistamine chlorpheniramine	10	NR	NR	HPLC and UV	Tablet shape, size, thickness, and weight; disintegration and friability tests	3/10(30%) substandard	Low API%
Ramachandran et al^Citation61	India	Anti-TB	1,948 tablets	NR	NR	Spectrometry	NR	168/1,948 (9%) substandard	Low and high API%
Khan et al^Citation62	Cambodia	Antibiotic amoxicillin- clavulanic acid	59	Contact with manufacturer and local authorities	Basic visual analysis of primary and secondary packaging	HPLC	Stability and dissolution	12/59 (20%) substandard	Low API%, failure of content uniformity and dissolution tests
Affum et al^Citation63	Ghana	Antimalarial artesunate and amodiaquine	32 blisters	NR	Basic visual analysis and compared to genuine	Titrimetric, HPLC, and spectrometry	Tablet weight	14/32 (43.75%) substandard	Low and high API% mostly artesunate
Briesen et al^Citation64	Kenya and Congo	Antibiotic eye drops	33	NR	NR	HPLC	NR	19/33 (58%) substandard	Low and high API%
Nogueira et al^Citation65	Brazil	Antimalarial medicines	9	NR	Simple package analysis	HPLC-UV	Dissolution, disintegration, hardness, uniformity of weight, and friability tests	4/9 (44%) substandard	Failing only visual inspection and uniformity of weight
El-Duah and Ofori-Kwakye^Citation66	Ghana	Antimalarial artemisinin-medicines	14	NR	For illegal print errors	Colorimetry and TLC	Uniformity of mass, crushing strength, and disintegration	13/14(93%) substandard	Low or high API% and failing physical tests
Karlage et al^Citation67	Mexico	Antibiotics, warfarin, levothyroxine and sildenafil	17	NR	NR	HPLC	Weight measurement	5/17(30%) substandard	Low API%
Pribluda et al^Citation68	Seven countries in South America	Antimalarial	1,663	NR	Package and label	TLC	Disintegration	193/1,663 (11%) substandard	Expired medicines mostly, low API%, and failure of disintegration tests
Klein et al^Citation69	Ghana	Antimalarial	33	NR	Package inspection	NMR	NR	1/33 (3%) substandard	Low API%
Ehianeta et al^Citation70	Nigeria	Antimalarial artesunate and amodiaquine combination	13	NR	Package inspection of expiry date and registration	HPLC	NR	11/13 (85%) substandard	Low and high API%
Bate et al^Citation71	17 countries from all continents	Antimalarial, antibiotics, and antituberculosis	899	NR	Package inspection	TLC and Raman	Disintegration	15% substandard	Failure of visual inspection, low API%, and dissolution failure
Seear et al^Citation72	India	Ciprofloxacin, artesunate, and rifampicin	300	NR	NR	HPLC-MS	NR	43% substandard	Low and high API%
Akpabio et al^Citation73	Nigeria	Antibiotic ciprofloxacin	4	NR	NR	Titration	Uniformity of weight, hardness, disintegration, dissolution, and friability	1/4 (25%) substandard	Low API%, failure of friability, and dissolution tests
Hadi et al^Citation74	Indonesia	Five different antibiotics	104	NR	Package inspection	HPLC	NR	18% substandard	Low API%
Bate and Hess^Citation75	Ghana and Nigeria	Antimalarial	339	NR	Package inspection	TLC and Raman	Disintegration	23% substandard	Failure of visual inspection, low API%, and dissolution failure
Leslie et al^Citation76	Pakistan	Antimalarial	9	NR	NR	HPLC	Dissolution	100% substandard	High API% and dissolution failure
Twagirumukiza et al^Citation77	Rwanda	Antihypertensive drugs	10	NR	NR	HPLC	Dissolution	2/10 (20%) substandard	Low and high API%
Ali^Citation78	Pakistan	Antibiotic ceftriaxone injection	96	NR	NR	HPLC	NR	15/96 (16%) substandard	Low and high API%
Bate et al^Citation79	Ghana, India, Kenya, Nigeria, Tanzania, and Uganda	Antimalarial, antibiotic, and anti mycobacterial	78	NR	NR	TLC, near- infrared spectroscopy, and Raman	Disintegration	40/78 (51%) substandard	Low API% and disintegration failure
Fotiou et al^Citation80	Thailand	Epoetin alfa-prefilled syringes	139	Checked batch numbers with manufacturer	Primary and secondary package and security features	HPLC, electrophoresis and Western blotting	NR	32/139 (23%) substandard and diverted	Exceeded specific content requirement for the product, and batch number matches products sold outside the country according to the manufacturer
Kaur et al^Citation81	Tanzania	Antimalarial	304	NR	NR	HPLC	Dissolution	12.5% substandard	Low API% and dissolution failure
Kyriacos et al^Citation82	Lebanon, Syria, Jordan, Egypt, and Saudi Arabia	Amoxicillin antibiotic in different formulations	1 1 1	NR	NR	HPLC	NR	56% of capsules substandard; 8% of suspensions substandard	Low API%
Meos et al^Citation83	Estonia and Russia	Antibiotic doxycycline	8	NR	Basic package inspection	HPLC	Dissolution	2/8 (25%) substandard	Low API% and dissolution failure
Bronnikova et al^Citation84	Estonia and Russia	Antibiotic amoxicillin	6	NR	Basic package inspection	HPLC and UV	Dissolution	1/6 (16%) substandard	Dissolution failure
Vijaykadga et al^Citation85	Thailand	Antimalarial	369	NR	Package and label	TLC and HPLC	Disintegration	23/369 (6%) substandard	Low API% and disintegration test failure
Lon et al^Citation86	Cambodia	Antimalarial	451	One company was investigated by contact with local authorities	Visual inspection Minilab^®	TLC	Disintegration	122/451 (27%) substandard	Low API% and disintegration test failure; one illegal manufacturer identified
Amin et al^Citation2	Kenya	Antimalarial	116	NR	Package and storage area inspection	UV and HPLC	Dissolution	47/116 (40%) substandard	Low API% and dissolution failure
Abdo-Rabbo et al^Citation87	Yemen	Antimalarial tablet and syrup	50	NR	NR	UV and HPLC	Dissolution	16/50 (32%) substandard	Low API%, high API% and dissolution failure
Rookkapan et al^Citation88	Thailand	Antituberculosis	52	One quality report was requested from a manufacturer	Tablet inspection	UV and HPLC	Dissolution	37% substandard	Failure of visual inspection, low API%, and dissolution failure
Kayumba et al^Citation89	Rwanda and Tanzania	Antimicrobial and antimalarial drugs	33	NR	NR	HPLC	Dissolution	4/33 (12%) substandard	Dissolution failure
Minzi et al^Citation90	Tanzania	Antimalarial	33	NR	Basic package information	TLC, HPLC	Dissolution	12/33 (36%) substandard	Low API% and dissolution failure
Obodozie et al^Citation91	Nigeria	Antibiotic in different formulation	22	NR	NR	HPLC	NR	9/22 (41%) substandard	Low and high API%
Laserson et al^Citation92	Seven different countries	Anti-TB	71	NR	Basic package information	TLC and LC-MS	NR	10% substandard	Low API%
Kenyon et al^Citation93	Botswana	Antituberculosis fixed-dose combination	13	NR	NR	TLC, LC, and UV	NR	4/13 (31%) substandard	Low and high API%

Abbreviations: API, active pharmaceutical ingredient; NR, not reported; HPLC, high-performance liquid chromatography; TLC, thin-layer chromatography; NIR, near-infrared spectroscopy; UV, ultraviolet spectroscopy; LC-MS, liquid chromatography-mass spectrometry; NMR, nuclear magnetic resonance spectroscopy; IR, infrared spectroscopy; TB, tuberculosis.

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