Biotech giant

Genentech

( DNA) received regulatory clearance in the U.S. for Lucentis, a drug designed to treat an eye disease that can progress until it ultimately leads to blindness.

Earlier in the day Friday, investors had already been expecting the approval and sent Genentech's shares up more than 3%. Recently, the stock rose $2.74, or 3.4%, to $82.87.

Lucentis will be used against a condition called wet age-related macular degeneration. The drug has performed well in clinical trials showing its efficacy, including one that involved a head-to-head comparison with another treatment, Visudyne from

Novartis'

(NVS) - Get Report

and

QLT

(QLTI)

. During the trial, Lucentis actually improved the vision of some patients.

While clinical trial results presented to the Food and Drug Administration to obtain marketing approval for a drug often compare the experimental product with a placebo, a direct comparison with an existing treatment is considered better evidence of its effectiveness, some researchers believe.

Genentech expects to ship the drug immediately. When Lucentis becomes available, Visudyne won't be its only competition. Another option for treating AMD is Macugen, a drug sold by

OSI Pharmaceuticals

( OSIP). OSI inherited Macugen when it acquired Eyetech Pharmaceuticals last year.