Turns out, everolimus is becoming quite the franchise for Novartis ($NVS). Sold under the Afinitor and Votubia names for tumor treatment and as Zortress and Certican for transplant patients, everolimus is one of the Swiss drugmaker's lead drugs in the post-Diovan era. And it just nabbed another approval, this time as Zortress, to prevent organ rejection in liver transplant patients.

The liver-transplant indication isn't nearly as lucrative as Afinitor's recent nod for breast cancer, which could eventually add $1 billion to $1.5 billion to the drug's annual sales. Right now, Afinitor brought in about $800 million last year--an increase of 85%--while the Zortress and Certican brands accounted for about $210 million, a 20% rise.

That $210 million in 2012 sales on the transplant side derived from approvals in heart and kidney transplant patients. There are more than 15,000 kidney transplants in the U.S. each year, and about 6,000 liver transplants annually, the National Institutes of Health says.