UPDATE 2-La Jolla says gets positive data from lupus drug trial

(Adds comments from company, analyst; updates share movement)

By Esha Dey

BANGALORE, April 23 (Reuters) - Biotechnology company La Jolla Pharmaceutical Co (LJPC.O: Quote, Profile, Research) said interim data from a late-stage trial of its lupus drug, Riquent, showed higher doses of the drug were more effective in reducing antibodies, sending its shares up as much as 24 percent.

Lupus is a potentially fatal, chronic autoimmune disease in which the body creates antibodies that attack the body's own connective tissues.

"Today's interim data is basically supportive of a similar data published by the company last year," Liana Moussatos, an analyst with Pacific Growth Equities said by phone.

Last May, the San Diego-based company said data from a late-stage trial showed higher doses of Riquent were more effective than the lower doses or a dummy drug.

Company spokesman Andrew Wiseman said data released Wednesday was for the complete 12 months of treatment, while the data announced last year was from the first eight weeks of the study.

"The new information is that they are going to enroll additional patients in the trial and the final data won't come out until the second half of 2009," Moussatos said.

La Jolla said it plans to enroll at least 800 patients in the study, above its initial target of 740.