Biopharmaceutical company QLT's ( QLTI) shares sank after the company said sales of its eye drug Visudyne fell nearly 29%.

The stock was 2.3% lower to $8.50 earlyThursday.

QLT's marketing partner Novartis ( NVS) says sales of the drug were approximately $76.5 million in the fourth quarter. Full-year Visudyne sales were $353.8 million, down 27% from 2005.

U.S. sales of the drug, which is used to treat vision loss caused by wet age-related macular degeneration, were $9.2 million in the fourth quarter, representing 12% of total sales, according to preliminary results.

Sales of QLT's Visudyne, as well as those of OSI Pharmaceuticals' ( OSIP) drug Macugen, have taken a hit since the approval of Genentech's ( DNA) drug Lucentis in June. In clinical trials, Lucentis was shown not only to stop vision loss, but also to improve vision in some patients.

QLT is slated to report its full earnings before the market opens on Feb. 22.

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