Public Statement of Pfizer's Thelin EU Marketing Authorization Withdrawal

The EMA has issued a statement addressing the withdrawal of the marketing authorization for Thelin, which was voluntarily withdrawn in 2010 because of a risk of serious liver injury.

Back in August 2006, the European Commission (EC) awarded the orphan designated Thelin (sitaxentan) marketing authorisation in the EU. Used to treat adults with pulmonary arterial hypertension, the endothelin receptor antagonist increases capacity for physical activity. Sixteen EU Member States consequently marketed Thelin.

On 10 Dec, 2010, Pfizer announced that it would cease clinical trials of Thelin and initiated a voluntary withdrawal of the product in the EU, Canada and Australia. Pfizer based this decision on safety information obtained from clinical trials and post-marketing reports. In a press release, the company stated: “While liver toxicity is a known complication of the class of drugs to which Thelin belongs, a new potentially life-threatening idiosyncratic risk of liver injury with Thelin has been observed.” Indeed, the withdrawal followed information on two cases of fatal liver injury.

On 6 Jan. 2011, the EC issued a decision confirming the withdrawal of the marketing authorization of Thelin and the European public assessment report has been updated to reflect the change. The EMA made a public statement addressing the withdrawal on 2 Mar. 2011.