UPDATE 2-Regeneron beats profit estimates, lifts Eylea's growth view

(Adds details, analyst comment; updates shares)

Aug 3 (Reuters) - Regeneron Pharmaceuticals Inc's quarterly profit handsomely beat estimates on strong demand for its flagship Eylea drug, helping the U.S. drugmaker raise its full-year growth forecast for the eye treatment.

Lower expenses and a significantly smaller tax rate also helped Regeneron beat analysts' estimates for adjusted profit by a dollar at $4.17 per share, sending the company's shares up 4.3 percent in premarket trading.

Sales of the drug, which is used to treat macular degeneration and other eye disorders, also beat analysts' estimates and rose 11 percent to $919 million in the United States.

Regeneron, which has largely relied on Eylea to grow since 2011, revised all aspects of its 2017 financial outlook in the positive direction on Thursday.

The company now expects U.S. Eylea sales to grow 10 percent over 2016, despite intensifying competition from rival drugs including Lucentis, owned by Roche Holding AG and Novartis AG.

Eylea raked in $3.32 billion in sales from the United States in 2016. Regeneron had previously estimated single-digit percentage growth. The U.S. biotech's second-quarter revenue also benefited from higher-than-expected collaboration revenue from partners Sanofi SA and Bayer AG.

Collaboration revenue rose to $432.5 million from $355.3 million and total revenue rose to $1.47 billion from $1.21 billion.

Analysts on average were expecting total revenue of $1.35 billion, according to Thomson Reuters I/B/E/S.

Regeneron is betting on its recently approved eczema treatment Dupixent and rheumatoid arthritis drug Kevzara to reduce its dependence on Eylea, which accounted for nearly 60 percent of its total revenue in the quarter.

However, investors were unhappy with Dupixent sales of 26 million euros ($30.85 million) in the drug's first full quarter on market, which was revealed by partner Sanofi earlier this week.

On Thursday, Regeneron confirmed the eczema drug generated a weaker-than-expected $29 million.

"Given the weakness in Regeneron over the last few days with the disappointing initial Dupixent number, the solid Eylea beat should improve perception," Morgan Stanley analysts said in a client note.

Dupixent is expected to secure European approval later this year, the company said.

Regeneron said it expected to submit a U.S. application to market the drug as a treatment for uncontrolled asthma.

The drugmaker's net income rose to $387.7 million, or $3.34 per share, in the second quarter ended June 30.

The Tarrytown, New York-based company's stock were at $497.50 in light premarket trading.

($1 = 0.8427 euros) (Reporting by Manas Mishra and Natalie Grover in Bengaluru; Editing by Saumyadeb Chakrabarty and Arun Koyyur)