April 22 (Reuters) - Life science real estate investment

trust (REIT) Alexandria Real Estate Equities ( ARE ) posted a

rise in funds from operations (FFO) for the first quarter on

Monday, aided by better occupancy rates.

The Pasadena, California-based company operates and develops

life science laboratories, offices and technology campuses

across North America with clients such as Bristol-Myers Squibb ( BMY )

, Moderna ( MRNA ) and Eli Lilly ( LLY ).

Alexandria's quarterly FFO, a key measure of performance of

a REIT, came in at $2.35 per share, compared with $2.19 per

share a year earlier.

Occupancy of operating properties in North America as of

March 31 stood at 94.6%, compared with 93.6% a year ago.

The company also raised its annual FFO forecast to be

between $9.49 and $9.61 per share, from previous range of $9.37

to $9.57 per share.

Its total revenue for the quarter ended March 31 rose nearly

10% to about $769 million.