A new study revealed that a kidney liver cancer drug called Nexavar has been shown to raise the blood pressure of patients taking it.

The authors of the study appeared in the January 22 online issue of Lancet Oncology suggested that patients taking Nexavar (sorafenib) should be carefully monitored by their physicians.

Nexavar was approved in 2005 to treat advanced kidney cancer and in 2007 for treating the most common form of liver cancer that can’t be surgically removed (unresectable hepatocellular carcinoma or HCC). The drug improved overall survival by 44 percent among people with HCC in clinical testing, which was considered a major discovery against one of the most voracious disease.

Nexavar, manufactured by Bayer AG and Onyx Pharmaceutical Inc., is approved for treating kidney cancer and liver cancer both in Europe and the United States.

“Early detection and effective management of hypertension might allow for safer use of this drug. Future studies will be needed to identify the mechanism and appropriate treatment of sorafenib-induced hypertension,” Shenhong Wu of State University of New York, Stoney Brook and colleagues wrote in their study, considered a meta-analysis of nine studies that included 4,599 patients and were published between January 2006 and July 2007.

The researchers discovered that patients treated with Nexavar have a 23 percent higher chance of having an increase in blood pressure than those not administered the drug.

In 2006, Nexavar sales hit 130 million euros and Bayer has already said that it expects the drug to reach 1 billion euros in annual sales if it gets approval for treatment of various cancer indications.

Liver cancer makes more than 600,000 million victims worldwide each year and is currently treated with limited success using a mix of surgery, radiation and chemotherapy.