The earnings beat, relative to investor expectations, was also due to cost controls, surging demand in China for its products and because Zyprexa's decline was not as steep as had been feared, said company spokesman Mark Taylor.
The Indianapolis drugmaker said on Wednesday it earned $1.01 billion, or 91 cents per share in the first quarter. That compared with $1.06 billion, or 95 cents per share, in the year-earlier period, when the company took a number of restructuring and research-related charges.
Excluding special items, Lilly earned 92 cents per share. Analysts, on average, had expected 78 cents per share, according to Thomson Reuters I/B/E/S.
The company's shares rose 2.2 percent in premarket trading.
"Lilly just reported what looks like a solid first quarter," ISI Group analyst Mark Schoenebaum said in a research note.
But Schoenebaum predicted its shares would not react in a major way since investors are more focused on the company's progress in developing solanezumab, its experimental Alzheimer's disease treatment, than on quarterly earnings.
Data from the drug's late-stage trial is expected later this year. Although the drug is considered to be a long shot, investors say it would have huge sales potential if shown to slow progress of the memory-robbing disease, and speed Lilly's return to profit growth.
Global company revenue fell 4 percent to $5.6 billion, little affected by foreign exchange rates, above Wall Street expectations of $5.36 billion.
Sales of Zyprexa, which lost U.S. patent protection in October, tumbled 56 percent to $563 million, while Cymbalta sales jumped 23 percent to $1.11 billion.
Although Cymbalta's growth helped offset declines for Zyprexa in the quarter, the depression drug's own U.S. patent will lapse in mid-2013. Its sales will then shrink dramatically, worsening Lilly's long-feared patent cliff.
Global sales of Alimta, the company's lung cancer drug, rose 5 percent to $607 million. Its Humalog insulin rose 12 percent to $590 million, while its Humulin insulin brand grew 6 percent to $308 million.
The company slightly raised its 2012 profit forecast to between $3.15 and $3.30 per share, excluding special items. In January, Lilly forecast $3.10 to $3.20 per share, far below analyst estimates, sending the drugmaker's stock down sharply.
(Reporting By Ransdell Pierson; Editing by Gerald E. McCormick and Maureen Bavdek)