Senior Staff Writer

Adding to its portfolio of eye disease therapeutics, Ista Pharmaceuticals licensed a calcium channel blocker and a prostaglandin from Senju Pharmaceuticals Co. Ltd.

The Irvine, Calif.-based company will cover all further development and regulatory costs in North America, as well as manufacturing and commercialization expenses, of iganidipine and a new formulation of latanoprost. It is paying Senju an up-front fee and development and approval milestones of $8 million for each product, or $16 million total. The products could reach the market by 2011, and the deal includes royalties back to Osaka, Japan-based Senju.

"We typically pay royalties that are in the mid- to upper-teens," said Vicente Anido, Ista's president and CEO, who added that most of the milestone payments are "back-end loaded. As we go into Phase III and get the products approved, that's when the bulk of those milestones are due."

Ista exclusively licensed the North American rights to the calcium channel blocker iganidipine and to a new formulation of the prostaglandin latanoprost to balance its portfolio of glaucoma products. Both treatments complement Istalol, a once-daily beta-blocker marketed for glaucoma, which was approved in June 2004 and had net sales of $1.8 million in the first quarter.

Like hypertension, glaucoma is treated with a variety of drugs. If the favorites don't work, physicians turn to other entities to reduce the blood pressure in hypertension or the intraocular pressure in glaucoma. For the latter indication, standard treatment is with a prostaglandin - specifically New York-based Pfizer Inc.'s Xalatan (latanoprost). Its sales were $477 million in 2005, and prostaglandins as a whole represent the largest segment of the U.S. glaucoma market with annual sales of about $700 million.

Although prostaglandins can drop ocular pressure by 30 percent to 35 percent, "roughly half of patients who get a prostaglandin prescription," Anido said, "also get another prescription," such as one for Istalol or Irvine, Calif.-based Allergan Inc.'s Alphagan P.

The new formulation of latanoprost licensed from Senju is an emulsion, as opposed to the current suspension formulation.

"We think it will be more comfortable for the patients," Anido said, adding that the formulation has "some interesting properties. We probably will have a better shelf life than the current product," since there is no need for refrigeration.

Ista expects to complete formulation development and optimization studies with latanoprost next year. The new version, which could earn Ista $50 million annually, cannot be launched "until 2011 when the product goes generic," Anido said.

He is expecting a similar timeline to approval for iganidipine, which could bring in "hundreds of millions of dollars" for Ista. Calcium channel blockers have not been approved to treat glaucoma, but early studies show iganidipine might have the ability to enhance ocular blood flow, lower intraocular pressure and inhibit the progression of visual field defects. Ista expects to start a Phase II study in the U.S. in 2007.

Glaucoma can lead to irreversible eye damage and eventual blindness if not treated. It is the second leading cause of blindness, accounting for an estimated 9 percent to 12 percent of all blindness cases in the U.S.

The Glaucoma Research Foundation reported that 3 million people in the U.S. have the disease and 120,000 new cases are documented annually. Its causes are not well understood.

Other firms working in the glaucoma space include Sophia Antipolis, France-based NicOx SA (working with Pfizer); Novagali Pharma SA, of Evry, France; and the young company Danube Pharmaceuticals Inc., of New York, which just completed a $10 million Series A round last week; among others. (See BioWorld Today, June 15, 2006.)

Aside from Istalol, Ista markets Vitrase as a spreading agent and Xibrom for ocular inflammation in patients who have undergone cataract extraction. It has submitted a new drug application for Vitrase to treat vitreous hemorrhage and is studying in Phase III trials Caprogel for hyphema and TobraPred for ocular inflammation and infection. At Phase II, it is developing ecabet sodium for dry eye, and Vitrase for diabetic retinopathy.

The addition of Senju's products brings the total number of drugs in development at Ista to six. "We think it gives us a fairly rich pipeline," Anido said, adding that the company "expects to add more this year."

Ista's stock (NASDAQ:ISTA) rose 16 cents Monday to close at $6.44.