UPDATE 3-Regeneron shares jump after CEO touts drugs

* Expects aflibercept colon, lung cancer data next year

* Says aflibercept has best chance against colon cancer

* Says drug may have less blood-clot risk than Avastin

* Shares close up 5.6 pct (Adds CEO quotes from interview, details on drugs)

By Ransdell Pierson

NEW YORK, March 23 (Reuters) - The CEO of Regeneron Inc (REGN.O) said on Tuesday his company expects late-stage data by the first half of 2011 on its experimental drug for colorectal and lung cancer, and that it could show a safety advantage over Roche Holding AG's (ROG.VX) blockbuster Avastin.

Shares of Tarrytown, New York-based Regeneron closed up 5.6 percent at $25.72 Tuesday on the Nasdaq, after Chief Executive Leonard Schleifer put the spotlight on aflibercept and other company drugs now winding their way through late-stage trials.

Partner Sanofi-Aventis (SASY.PA) is paying all costs of developing the oncology product, aflibercept, which is also being tested against prostate cancer. Interim data from late-stage trials for that cancer are expected in mid-2011.

But Schleifer said aflibercept probably has the best chance of succeeding against colorectal cancer. He noted it works through a similar mechanism as Avastin, which is one of the leading approved treatments for that cancer.

Aflibercept and Avastin both block a protein called VEGF that tumors use to build blood vessels capable of supplying themselves nutrients.

But Avastin and other anti-VEGF drugs cause blood clots, presumably by causing sticky blood cells called platelets to clump together, Schleifer said in a presentation at the annual Barclays Capital Global Healthcare Conference in Miami.

"There is reason to expect our drug doesn't activate platelets," providing a possible safety advantage over rival anti-VEGF drugs, Schleifer said.

Regeneron is also conducting late-stage trials of drugs meant to treat gout and macular degeneration, a leading cause of blindness.

Schleifer said the company expects late-stage data in the the second quarter on use of its drug, Arcalyst (rilonacept), to prevent gout flares and to treat acute gout -- an intensely painful form of arthritis.

He said Regeneron expects late-state data in the second half of this year on its medicine for macular degeneration, called VEGF-TRAP, whose active ingredient is aflibercept.

By developing an eye drug with its VEGF-inhibitor, Regeneron is following a trail blazed by Roche. The Swiss drugmaker also sells a treatment for macular degeneration, Lucentis, whose active ingredient is very similar to Avastin.

Regeneron also hopes to receive "proof-of-concept" data in the second quarter from an early-stage human trial of an experimental drug that cut "bad" LDL cholesterol 70 percent in primate studies. It works by blocking a protein called PCSK9.

"It's one of the most exciting new targets in biotechnology," Schleifer told Reuters in an interview, noting the drug is among a handful of monoclonal antibodies being tested in human trials under a 3-year-old deal with Sanofi.

Regeneron aims to begin trials of 30 to 40 other antibodies in the next eight years, under the Sanofi partnership.

"This is a year chock full of data for us and the depth and breadth of our pipeline, with eight biologics in development, is really just beginning to be appreciated," Schleifer said.

"I would aspire over time to achieve what some of the larger and more successful biotechnology companies have done, such as Genentech and Amgen," he said, adding that success will be measured by how many significant drugs Regeneron launches.

Sanofi provides Regeneron $160 million a year that it uses to discover new antibodies, and pays 100 percent of later costs to test the experimental drugs in clinical trials. In return, Schleifer said Regeneron will be entitled to very hefty royalties on drugs that succeed in trials and are approved.

Sanofi's funding represents a "substantial" percentage of the $750 million Regeneron will spend this year on research and development, Schleifer said, a strong endorsement of the company by far-larger Sanofi.

"It's also a big vote of confidence of us in Sanofi because we hooked up with them," said Schleifer. "And I feel strongly about that." (Reporting by Ransdell Pierson; editing by Matthew Lewis, Bernard Orr)