Chemical Analysis of Counterfeit Hepatitis C Drug Found in Japan

In January 2017, counterfeits of the hepatitis C drug 'HARVONI^® Combination Tablets' (HARVONI^®) were found at a pharmacy chain through unlicensed suppliers in Japan. A total of five lots of counterfeit HARVONI^® (samples 1-5) bottles were found, and the ingredients of the bottles were all in tablet form. Among them, two differently shaped tablets were present in two of the bottles (categorized as samples 2A, 2B, 4A, and 4B). We analyzed the total of seven samples by high-resolution LC-MS, GC-MS and NMR. In samples 2A, 3 and 4B, sofosbuvir, the active component of another hepatitis C drug, SOVALDI^® Tablets 400 mg (SOVALDI^®), was detected. In sample 4A, sofosbuvir and ledipasvir, the active components of HARVONI^®, were found. A direct comparison of the four samples and genuine products showed that three samples (2A, 3, 4B) are apparently SOVALDI^® and that sample 2A is HARVONI^®. In samples 1 and 5, several vitamins but none of the active compounds usually found in HARVONI^® (i.e., sofosbuvir and ledipasvir) were detected. Our additional investigation indicates that these two samples are likely to be a commercial vitamin supplement distributed in Japan. Sample 2B, looked entirely different from HARVONI^® and contained several herbal constitutents (such as ephedrine and glycyrrhizin) that are used in Japanese Kampo formulations. A further analysis indicated that sample 2B is likely to be a Kampo extract tablet of Shoseiryuto which is distributed in Japan. Considering this case, it is important to be vigilant to prevent a recurrence of distribution of counterfeit drugs.

Substandard and counterfeit medicines: a systematic review of the literature

OBJECTIVE

To explore the evidence available of poor-quality (counterfeit and substandard) medicines in the literature.

DESIGN

Systematic review.

DATA SOURCES

Databases used were EMBASE, MEDLINE, PubMed and the International Pharmaceutical Abstracts, including articles published till January 2013.

ELIGIBILITY CRITERIA

Prevalence studies containing original data. WHO definitions (1992) used for counterfeit and substandard medicines.

STUDY APPRAISAL AND SYNTHESIS

Two reviewers independently scored study methodology against recommendations from the MEDQUARG Checklist. Studies were classified according to the World Bank classification of countries by income.

DATA EXTRACTION

Data extracted: place of study; type of drugs sampled; sample size; percentage of substandard/counterfeit medicines; formulations included; origin of the drugs; chemical analysis and stated issues of counterfeit/substandard medicines.

RESULTS

44 prevalence studies were identified, 15 had good methodological quality. They were conducted in 25 different countries; the majority were in low-income countries (11) and/or lower middle-income countries (10). The median prevalence of substandard/counterfeit medicines was 28.5% (range 11-48%). Only two studies differentiated between substandard and counterfeit medicines. Prevalence data were limited to antimicrobial drugs (all 15 studies). 13 studies involved antimalarials, 6 antibiotics and 2 other medications. The majority of studies (93%) contained samples with inadequate amounts of active ingredients. The prevalence of substandard/counterfeit antimicrobials was significantly higher when purchased from unlicensed outlets (p<0.000; 95% CI 0.21 to 0.32). No individual data about the prevalence in upper middle-income countries and high-income countries were available.

LIMITATIONS

Studies with strong methodology were few. The majority did not differentiate between substandard and counterfeit medicines. Most studies assessed only a single therapeutic class of antimicrobials.

CONCLUSIONS

The prevalence of poor-quality antimicrobial medicines is widespread throughout Africa and Asia in lower income countries and lower middle-income countries . The main problem identified was inadequate amounts of the active ingredients.