ISTA Pharmaceuticals Inc. released positive Phase III findings for its eye drug Xibrom, showing a statistically significant absence in ocular inflammation following treatment.
The company plans to file a new drug application in the second quarter. If approved, it could be launched in the first half of 2005.
ISTA's stock (NASDAQ:ISTA) rose about 17 percent, or $1.87, on Tuesday's news, closing at $12.62.
The positive results pleased officials of the Irvine, Calif.-based company, which held a conference call Tuesday morning.
"As expected, we did achieve efficacy on twice-a-day dosing with a very favorable safety profile," said Vicente Anido, the company's CEO. "As a result of the data we will begin working very quickly to file an NDA for this drug sometime in the second quarter of this year."
Xibrom (bromfenac sodium ophthalmic solution) is a topical, non-steroid solution being developed to treat ocular inflammation following cataract surgery. It offers an advantage to currently marketed products because of its twice-daily dose. Its competitors are dosed four times daily.
"Clearly, the twice-a-day vs. the four-times-a-day dosing is a major advantage for us," Anido said. "The clean side effect profile vs. what is available is also a strong message."
ISTA began its Phase III program as one large trial, later splitting it into two double-masked, placebo-controlled trials in the U.S.
The first study involved 296 patients at 20 sites. It showed that 62.6 percent of Xibrom-treated patients cleared their ocular inflammation at 15 days, compared to 39.8 percent of placebo patients.
The second study, involving 231 patients at 19 sites, showed Xibrom again did better than placebo in clearing ocular inflammation at 65.8 percent and 47.9 percent, respectively. Both trials reached statistical significance with a "p" value of less than 0.01. The primary endpoint of complete absence of ocular inflammation was measured by an assessment of immune cells in the anterior chamber of the eye and cellular debris.
While the company is still analyzing the results, researchers noticed a treatment effect could be seen very early in both trials.
"We saw efficacy as early as three days following initiation of treatment," Lisa Grillone, ISTA's vice president of clinical research and medical affairs, said in the conference call.
Xibrom also showed a statistically significant benefit in the secondary endpoints of both trials - inflammation clearance in patients only on the assigned treatment and no other medications. In the first study, the rates of clearance were 57.6 percent for Xibrom and 23.5 percent for placebo. In the second study, the rates were 62 percent for Xibrom and 31.5 percent for placebo.
Xibrom was well tolerated with a low incidence of ocular adverse events - consistent with results of previous Japanese studies conducted by developer Senju Pharmaceuticals Co. Ltd., of Osaka, Japan.
Only 3.5 percent of Xibrom-treated patients in the first study experienced burning and stinging, compared with 6 percent of patients in the placebo arm. Results from the second study were similar.
"The incidence that you see here for a variety of ocular adverse events is extremely low," Grillone said.
ISTA gained product rights for Xibrom in May 2002 through its acquisition of AcSentient Inc., of Research Triangle Park, N.C. AcSentient had acquired the rights from Senju, which launched the product in Japan in 2000.
ISTA plans to market the product itself in the U.S.
"We have not partnered this product out. We do not expect to partner this product out," Anido said. "We will expand the sales force this year to have a 2005 sales force of 60 people."
Aside from Xibrom, ISTA has a few other products nearing the market.
The company is awaiting a decision on Vitrase as a single injection to the eye for vitreous hemorrhage. The FDA issued an approvable letter last year. (See BioWorld Today, April 8, 2003.)
ISTA also has a pending amendment to its Vitrase NDA to use it as a spreading agent that would facilitate the dispersion and absorption of other drugs.
Last summer, the company received an FDA approvable letter for Istalol to treat glaucoma. Istalol, a liquid, once-per-day formulation of the beta-blocker timolol, also was developed by Senju. (See BioWorld Today, July 29, 2003.)
In addition to Istalol and Xibrom, ISTA acquired worldwide marketing rights to Caprogel, a compound to treat hyphema, from Senju through its acquisition of AcSentient.