West Coast Editor

InSite Vision Inc. hit the primary endpoint - equivalence to tobramycin, with reduced dosing - in a Phase III trial with its longer-lasting version of topical azithromycin for pink eye.

"Our impression is, nothing is available presently that has such characteristics, and from my own viewpoint, nothing is under development that has such characteristics," Kumar Chandrasekaran, CEO of Alameda, Calif.-based InSite, told investors during a conference call.

The company's stock (AMEX:ISV) closed Wednesday at 89 cents, up 13 cents.

Top-line data from the pivotal, 746-patient study with AzaSite at 47 sites showed the compound, formulated by way of the firm's DuraSite system, gained a clinical resolution rate for patients with bacterial conjunctivitis of 80 percent, as compared to 78 percent for tobramycin.

The dosage for AzaSite was twice a day for the first two days, followed by once per day for the next three days. Tobramycin-treated patients got their dose four times per day for five days. InSite plans to file a new drug application next year.

The company disclosed plans in the summer of 2004 for a pair of Phase III trials - one comparing AzaSite with placebo and the other comparing the drug with tobramycin, which is a "highly effective, approved and marketed drug" for pink eye, Chandrasekaran noted Wednesday. (See BioWorld Today, Aug. 12, 2004.)

Results from both studies are expected to be detailed in an upcoming scientific meeting.

"I don't expect additional data will be presented before then," Chandrasekaran said, adding that he tries to "play things rather conservatively because at this stage of the game, one doesn't want to be unduly optimistic."

Still, Eugene Protzko, clinical instructor at the University of Maryland School of Medicine and a principal investigator in the trial, called 80 percent "pretty high," especially given the standards of disease measure demanded by the FDA, which call for the taking of eye cultures during the treatment period.

"You're going to have some noise that limits you [to] that 80 percent," he said, adding that the cure rate would probably rise in a physician's clinical practice.

Chandrasekaran, who estimated AzaSite's market size at $200 million, said InSite is "in active discussions with several potential partners, and these are all relatively late stage," with a disclosure likely "before the end of this year" on that score.

"At this day and age, everyone wants instant gratification," he said, pointing out that other products in the InSite hopper have "generated a lot of interest" and the firm is sorting through would-be partners carefully.

"We've tried to compartmentalize them, from the standpoint of let's make a deal with AzaSite [first]," Chandrasekaran said.

Meanwhile, the company's quarterly report for the period ending Sept. 30 lists total assets of about $3.3 million, and liabilities of about $2.9 million.

InSite is investigating "financing options that, to as high an extent as possible, would be non-dilutive or minimally dilutive," Chandrasekaran said, acknowledging that the firm may have to do an interim financing.

"One thing we have always been very careful about is to have a great discipline in how we spend our money and how we can extend the resources we presently have," he said, adding that officials are "very cognizant" about the present situation and aim to "ensure there is no gap in monies on our balance sheet and what we require for operations."

Down the road, InSite plans to seek approval for a version of AzaSite combined with a steroid. TobraDex, the combination of tobramycin and dexamethasone marketed by Alcon Labs Inc., of Fort Worth, Texas, sold $250 million last year, Chandrasekaran said, and the amount is expected to reach "close to $300-plus million" this year.

Approved in late 1980, TobraDex is due for patent expiration soon, he said - Alcon's website noted that the "patents run to 2007" - and InSite's steroid version of AzaSite would compete with generic forms of TobraDex.