Detection of Pyrogens in Hormonal Implants Using the LAL Test

The State Pharmacopoeia of the Russian Federation, 14th edition states that implants are a sterile dosage form, and have to be tested for pyrogens. However, it does not provide details on how the test should be performed for this dosage form.

The aim of the study was to develop a LAL test procedure for detection of bacterial endotoxins (BE) in implants, using the example of a goserelin product.

Materials and methods: BE extraction from the implant surface into an aqueous medium was performed with subsequent BE detection in the extract by turbidimetric kinetic test. The implant was then dissolved in dimethyl sulfoxide, and the obtained goserelin solution was tested for BEs using the gel-clot test.

Results: the analysis of the Russian and foreign pharmacopoeial approaches to pyrogenic substance detection in hormonal implants helped to develop two sample preparation procedures for determination of BE content (in the extract and the implant solution). It was demonstrated that the BE content in the water extract did not exceed 0.01 EU/mL and was less than 0.07 EU per implant. The BE content in the implant solution was less than 8.3 EU per 1 mg of goserelin, which is almost eleven-fold lower than the theoretically-derived limit.

Conclusions: the authors developed two test procedures for BE detection in hormonal implants using the LAL test, which could be included in manufacturers’ product files. The first procedure involves testing of the water extract from the implant surface and establishes the BE limit of no more than 20 EU/product. The second procedure involves complete dissolution of the implant in dimethyl sulfoxide and establishes the limit of not more than 97.22 EU per 1 mg of goserelin.

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