Drug wholesaler AmerisourceBergen Corp reported higher-than-expected fiscal fourth-quarter earnings on Tuesday, driven by strong sales in its generic and specialty drug businesses.

Net earnings rose 4.3 percent to $147.3 million, or 54 cents a share, compared with the year-ago quarter. Revenue rose 3.5 percent to $20.4 billion.

Excluding one-time items, the company earned 61 cents a share. Analysts on average had expected earnings of 56 cents a share, according to Thomson Reuters I/B/E/S.

Adjusting for a more normalized tax rate, AmerisourceBergen's adjusted EPS came in at 59 cents, still ahead of our and consensus estimates by 3 cents, said A.J. Rice, an analyst at Susquehanna Financial Group, in a research note.

AmerisourceBergen expects earnings per share for fiscal 2012 to be in the range of $2.74 to $2.84 a share.

Previously, AmerisourceBergen had suggested a $2.70 to $2.82 range, said Tom Gallucci, an analyst at Lazard Capital Markets. The increase is due primarily to buyback activity in recent months.

Analysts expect full-year earnings of $2.81 a share.

The Valley Forge, Pennsylvania-based company said it anticipates flat to modest revenue growth in fiscal 2012.

Outstanding performance in the two key growth drivers for our business - generic pharmaceuticals and specialty distribution and services, continues to drive gross margin expansion, said Steven Collis, the company's chief executive officer, in a statement.

In September, the company agreed to buy TheraCom LLC, a unit of CVS Caremark Corp for $250 million to expand its consulting services.

The company's shares fell 1.7 percent to $40.11 a share on the New York Stock Exchange in early trading, slightly less than a decline of 2.2 percent in the Dow Jones Industrial Average. <.DJI>

(Reporting by Toni Clarke in Boston; Editing by Maureen Bavdek, Dave Zimmerman)