Randox aspirin-resistance test gets TGA tick

The TGA has approved a test from Randox Laboratories to determine whether patients taking aspirin to reduce heart attack risks are benefiting from the treatment.

An estimated 25% of the population is resistant to the beneficial effects of aspirin and would better benefit from alternative treatments.

The Randox test, TxB Cardio, has now been cleared for use in Australian laboratories to help determine patients’ resistance to aspirin.

Aspirin’s primary action is to inhibit the production of thromboxane in the blood, helping prevent blood clotting. But methods of directly measuring blood thromboxane levels are unreliable. TxB Cardio instead measures a direct urinary metabolite of thromboxane.

TxB Cardio is an automated assay designed for use with routine laboratory implements. It is the first automated assay of its kind in the global market.

In an interview posted on YouTube, Dr Paul Ames, a consultant in haemostasis and thrombosis at Queen Mary University, London, said the efficacy of aspirin can reduce from 25% in non-resistant patients to 20% or 15% in those with a resistance.

“So you want to make sure that people who are on aspirin in fact do respond to aspirin the way they should,” he said.

Ames added that the properties of the TxB Cardio test make it “far superior” to conventional tests for aspirin resistance.