CHICAGO, June 4 (Reuters) - A kidney cancer drug became the first medicine to extend the life of patients with advanced liver cancer in a large study, adding about three months to survival compared with a placebo, according to a data released on Monday.
The trial found the biotechnology drug, Nexavar, by German drugmaker Bayer AG and its U.S. partner Onyx Pharmaceuticals Inc., extended survival by 10.7 months, compared with 7.9 months for a placebo -- a 44 percent survival benefit.
Of the roughly 100 clinical trials in liver cancer in 30 years, all have been negative, according to Joseph Llovet, director of liver cancer research at Mount Sinai School of Medicine in New York, who led the trial.
"This constitutes the dawn of a new era" for liver cancer, said Philip Johnson, of the Institute for Cancer Studies at Birmingham University in the United Kingdom, who was asked to critique the study in a special session at the American Society of Clinical Oncology's annual meeting in Chicago.
The news spurred rise of more than 8 percent in the stock of Onyx, a biotechnology company based in Emeryville, California. The shares of Bayer, a far larger company, were little changed.
Liver cancer kills 622,000 people globally each year and is treated with a mix of surgery, radiation and chemotherapy. But there are no effective treatments when these aggressive options fail and Bayer and Onyx hope to be first to fill that treatment gap.
Because of the survival advantage, the 600-person study was halted early so all patients taking part could receive Nexavar, taken in pill form.
"People will start to use this drug off-label for liver cancer as a result of this study," said William Blackstock, professor of radiation oncology at Wake Forest University School of Medicine.
Off-label drug use refers to administration of a medicine to treat a condition for which it is not officially approved. The practice is legal because once a medicine is approved, doctors can use it to treat any condition.
Blackstock said the survival advantage was "an important finding," but he stopped short of calling it a breakthrough.
The favorable result led Bear Stearns to raise its rating on Onyx shares to "outperform" from "peer perform," according to theflyonthewall.com.
The liver cancer data on Nexavar, among a new wave of treatments targeting cell receptors to block cancer growth, were presented at the American Society of Clinical Oncology's annual meeting in Chicago, where tens of thousands of cancer experts are gathering.
The limitations of the study include the fact patients tested had relatively good liver function and were primarily Europeans, Johnson said.
GROWING IN THE U.S.
Although relatively uncommon in the United States, liver cancer is the third biggest cause of cancer deaths worldwide, largely due to the high incidence of hepatitis abroad that can lead to liver cancer, according to the World Health Organization.
Nexavar, known generically as sorafenib, is being tested against several types of cancer.
"There's a great deal more to come," Onyx Chief Executive Hollings Renton told CNBC. "We're working hard to get this drug developed broadly for all kinds of cancers."
Bayer plans to submit its full applications seeking approval to sell the drug for liver cancer with U.S. and European regulators this summer, according to a spokesman.
The drug has so-called "orphan status" in both regions, which will give it an extended period of exclusive marketing, because of the lack of treatments for the disease.
Liver cancer is primarily caused by exposure to the hepatitis B and C viruses, which can occur through sharing dirty needles, unprotected sex, in childbirth and from blood transfusions. Alcohol and smoking are other risk factors.
Once the viruses are acquired, they can take several decades to engender cancer. The incidence of liver cancer is rising at varying rates throughout the world because of the timing of viral exposure of different populations.
In the United States, liver cancer kills about 17,000 people annually, but the rate is growing faster than in many other countries.
Onyx shares closed up $2.64 at 33.52 on the Nasdaq.
(Additional reporting by Bill Berkrot and Ransdell Pierson in New York and Julie Steenhuysen in Chicago)
