Liver test takes shine off Exanta
pharmafile | October 29, 2003 | News story | |Â Â Â
AstraZeneca has admitted that patients on its new anti-clotting drug Exanta will need liver tests, denting the drug's profile as a medical advance.
"I would anticipate that some form of liver function testing in clinical practice will be necessary", Dr Hamish Cameron, Vice President and head of Exanta development at AstraZeneca, told Reuters.
The drug would still require far less patient monitoring than older drugs such as standard treatment combination of warfarin, he added.
New trial data showed that 9.9% of patients taking Exanta had raised liver enzymes, a potential sign of toxicity, compared with just 2% of patients receiving older drugs.
The company said the raised enzymes were not associated with any specific clinical symptoms and decreased spontaneously.
Results from the six-month THRIVE Treatment study showed Exanta to be as effective as the current standard treatment of enoxaparin (RPR Clexane) and warfarin, on which patients need to be checked daily or every other day when they begin treatment.
Exanta is the first in a new class of anticoagulants the oral direct thrombin inhibitors (DTI) and the first oral anticoagulant since warfarin was introduced over 50 years ago.
"Patients taking Exanta benefit from at least as effective anti-thrombotic protection as those treated with well-controlled warfarin, but without the limitations of warfarin treatment or its requirement for time and cost-intensive coagulation monitoring and dose titration", the company said in a statement.
"These promising efficacy results need to be considered alongside the safety profile for Exanta emerging from this study and from other clinical trials, which will define its overall benefit-risk profile".
Exanta has been submitted to European regulatory authorities for the prevention of venous thromboembolism following surgery, with a US submission for this indication due in the fourth quarter of this year. AstraZeneca also plans to submit the drug in the US and Europe as a stroke prevention treatment in the fourth quarter of 2003.
Exanta is predicted to reach peak year sales of $3 billion in an anti-thrombotic market currently worth $9.6 billion.
