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Aug 1 (Reuters) - Pfizer Inc reported quarterly revenue on Tuesday that missed Wall Street estimates, driven by lower demand for its rheumatoid arthritis treatment Enbrel and pneumonia vaccine Prevnar.
Sales of Enbrel, which Pfizer sells outside the United States and Canada, tumbled about 19.5 percent to $617 million on competition from biosimilars.
Prevnar sales declined 8.2 percent to $1.15 billion, while sales of its breast cancer treatment, Ibrance, earned $853 million, up from $514 million in the year-ago quarter.
Sales of its copycat generics and biosimilars fell 13.5 percent in the quarter to $5.23 billion, while revenue from its patent-protected drugs rose about 8 percent to $7.67 billion.
Overall, revenue fell to $12.9 billion in the second quarter from $13.15 billion, below analysts' estimates of $13.08 billion, according to Thomson Reuters I/B/E/S. However, net income attributable to the largest U.S. drugmaker rose to $3.07 billion, or 51 cents per share, from $2.05 billion, or 33 cents per share, a year earlier.
Excluding items, Pfizer earned 67 cents per share, beating the average analysts' estimate by a cent.
Looming patent expirations on Pfizer's sexual dysfunction treatment Viagra, pain drug Lyrica and falling Prevnar sales has pushed analysts to prescribe deals to resuscitate the company's growth.
"Over the next five years, we project the potential for approximately 25 to 30 approvals, of which up to 15 have the potential to be blockbusters," Chief Executive Ian Read said in a statement on Tuesday.
The drugmaker also narrowed its 2017 adjusted earnings forecast to a range of $2.54 per share to $2.60 per share. It had previously forecast a range of $2.50 per share to $2.60 per share.
The company's shares were marginally up at $33.30 before the bell on Tuesday. (Reporting by Natalie Grover in Bengaluru; Editing by Arun Koyyur)