OSI Pharmaceuticals Inc.'s Tarceva - partnered with Genentech Inc. - won FDA approval in combination with gemcitabine as a first-line treatment in patients with pancreatic cancer who have not received prior chemotherapy, based on an overall survival benefit demonstrated in a Phase III trial.

It marks the second indication for Tarceva (erlotinib), a once-daily oral tablet, which already is used in non-small-cell lung cancer (NSCLC) in patients whose disease has progressed after chemotherapy. The supplemental new drug application filed in April requested clearance for the drug to be administered at 100-mg doses with gemcitabine in patients with unresectable or metastatic pancreatic cancer.

"This is an important step forward for the patients with pancreatic cancer," said Pablo Cagnoni, OSI's vice president of medical affairs and translational research. "This adds a new treatment option for them."

Shares of OSI (NASDAQ:OSIP) gained $1.45 after the news was released Wednesday afternoon. The stock rose an additional 99 cents Thursday to close at $24.72.

Pancreatic cancer is the fourth leading cause of cancer deaths in the U.S., although it makes up only 2 percent of new cancer cases each year. The American Cancer Society estimates that in 2005 about 32,000 people in the U.S. will be diagnosed with pancreatic cancer. Worldwide that number totals about 216,000.

"The number of new cases each year and the number of deaths each year is about the same, unfortunately," Cagnoni told BioWorld Today.

Tarceva, a small-molecule tyrosine kinase inhibitor, works by targeting the epidermal growth factor receptor (EGFR) pathway and preventing actions mediated by the receptor, including cell proliferation and rapid cell division.

Its ability to prolong survival in pancreatic cancer patients was observed during a two-year pivotal Phase III PA31 study involving 569 subjects. Data demonstrated that treatment with 100 mg of Tarceva plus gemcitabine resulted in a 23 percent longer survival rate compared to gemcitabine alone. At the end of one year, 24 percent of the patients receiving both drugs were still alive, compared to 19 percent receiving only chemotherapy. (See BioWorld Today, Sept. 21, 2004.)

"It's the first drug to show statistically significant improvement in survival benefit compared to gemcitabine alone," said Cagnoni, who reviewed those trial results before the FDA's Oncologic Drugs Advisory Committee in September.

ODAC voted 10-3 in favor of the expanded label, despite concerns raised by an FDA investigator regarding the drug's safety profile, specifically citing a 2.3 percent incidence of stroke in the Tarceva arm, compared to none in the placebo group, as well as possible increased risks of cardiovascular complications and interstitial lung disease. (See BioWorld Today, Sept. 14, 2005.)

Cagnoni said the "few side effects are not uncommon" for cancer treatments, and data from the PA13 trial "are clear that Tarceva plus gemcitabine is safe and well tolerated by the vast majority of patients."

Though the FDA is not bound by ODAC's recommendation, "we fully expected approval to be granted based on the data," he added.

OSI declined to disclose projected sales figures for Tarceva in the pancreatic cancer indication, though the drug has pulled in more than $200 million since it was launched last November to treat NSCLC. In the third quarter, U.S. sales of Tarceva totaled $73.2 million, as recorded by South San Francisco-based Genentech.

Genentech's stock (NYSE:DNA) closed at $92.84 Thursday, up $1.09.

Outside the U.S., Tarceva is marketed by Basel, Switzerland-based F. Hoffmann-La Roche Ltd. The drug received approval in the European Union in September for NSCLC, and is awaiting action on a marketing authorization application for pancreatic cancer.

In addition to those first two indications, OSI and Genentech are conducting "more than 100 clinical trials with Tarceva in almost every type of solid tumor," Cagnoni said. "We're exploring its use in earlier stages of lung cancer, ovarian cancer, head and neck cancer and other cancers."

OSI, which posted its earnings earlier this week, reported a net loss of $20 million, or 39 cents per share, for the three months ending Sept. 30. As of that date, the company had cash and investments totaling $560.7 million.