Pfizer pulls hypertension drug Thelin off the markets and ends studies because of liver damage

"Pfizer Inc. has said it is pulling its blood pressure drug Thelin off the market and stopping all clinical trials because the drug can cause fatal liver damage. Thelin is sold in the European Union, Canada, and Australia as an oral treatment for severe pulmonary arterial hypertension, or high blood pressure in the pulmonary artery. Pfizer said two patients who were taking Thelin died during a clinical trial, and a review of data from clinical studies and post-marketing reports showed a new link to liver injury. Liver damage was a known side effect of Thelin and similar drugs, the company said, but the review uncovered a link to liver damage that was not tied to identifiable risk factors. It said the problem was unlikely to be detected by routine monitoring, and in some cases, the problems did not go away after patients stopped taking Thelin. Pfizer said the withdrawal was voluntary and added that it has withdrawn its filing for marketing approval in the U.S."