TGA Laboratories testing report: Microbiological testing of medicines containing Green-lipped Mussel

On this page: Introduction | Testing | Outcome

Introduction

Complementary medicine oral dosage forms on the ARTG that contain green-lipped mussel (Perna canaliculus) as the active ingredient are generally indicated to help reduce joint pain.

Green-lipped mussels are marine shellfish that are efficient filter feeders, concentrating microorganisms, algal biotoxins and chemical pollutants from the waters in which they are farmed and harvested. Consumption of contaminated shellfish can cause serious adverse effects in humans. From 2017 to 2019 the TGA Laboratories undertook testing projects to monitor the microbiological quality of medicines containing green-lipped mussel supplied in Australia.

Complementary medicines containing green-lipped mussel that are supplied in Australia must comply with Therapeutic Goods (Microbiological Standards for Medicines) (TGO 100) Order 2018^[1], clause 11(2), Schedule 1, in relation to microbial count and absence of specified microorganisms. TGO 100 also requires medicines to be free from contamination with objectionable organisms. Vibrio parahaemolyticus and Listeria monocytogenes are examples of objectionable organisms that could contaminate medicines derived from shellfish and pose a risk to consumer safety. As such, these medicines are expected to be free from contamination with these objectionable organisms. See Table 1 for the acceptance criteria applied.

Testing

Testing was performed on twenty seven medicines. Twenty five complied with the requirements of clause 11(2), Schedule 1, of TGO 100 and two failed to comply with this clause (see Table 2).

No specified or objectionable organisms were isolated from any of the samples tested. For one product, the average Total Aerobic Microbial Count for one of three replicate containers tested exceeded the maximum permitted level. For a second product, one of the three containers tested exceeded the maximum permitted level for Bile-tolerant Gram negative bacteria.

One medicine was found not to comply with the labelling standard TGO 92 Standard for labels of non-prescription medicines (TGO 92).

TAMC = Total Aerobic Microbial Count, TYMC = Total Yeast and Mould Count

* To take into consideration the precision of the microbial plate count method, TGO 100 allows a maximum factor of 2 to be applied to the TAMC, TYMC, and Bile-tolerant Gram negative (BTGN) bacteria count criteria (when tested by plate count methods). For example, where the specification is not more than 10⁴ CFU per gram, then the maximum permitted count is 2.0 x 10⁴ CFU/g. The TAMC for one of three replicates was 2.7 x 10⁴ CFU/g, which exceeded the maximum level of 2.0 x 10⁴ CFU/g permitted by TGO 100.
(est.) = estimate (when there are less than 25 colonies on a count plate the result is reported as an estimate only).

Outcome

Twenty seven medicines, representing approximately one third of those on the ARTG containing green lipped mussel, were tested for microbiological quality during the 2017 - 2019 period. Twenty five complied with the requirements of clause 11(2), Schedule 1, of TGO 100 and two did not comply.

The two compliance failures were not safety-related and were considered to be minor product quality concerns. Product sponsors were informed of the test results and asked to investigate potential root causes for the elevated counts. Both provided evidence to show that other product batches were unlikely to be affected. Their proposed actions to address the minor quality concerns were considered satisfactory.

A separate medicine was found not to comply with the labelling standard TGO 92 Standard for labels of non-prescription medicines (TGO 92); this matter was referred to the Complementary & OTC Medicines Branch, who undertook a compliance review, following which the matter was resolved.