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Thursday, February 23, 2006

Diabetic Macular Edema trial with Retisert; Positive Results for pSivida

2/21/2006 12:47:40 PM

Diabetic Macular Edema trial with Retisert; Positive Results for pSivida

Global bio-nanotech company pSivida Limited today announced the publication of preliminary three year follow-up data from Bausch and Lomb's multi-center, randomized, controlled clinical trial of Retisert for the treatment of diabetic macular edema (DME). Global eye health company, Bausch and Lomb, exclusive licensee of Retisert from pSivida, conducted the study in hospitals in the United States in which 197 patients were randomized to receive either standard of care (repeat laser or observation) or a Retisert implant. The study concluded that significantly more patients receiving a Retisert implant had improved visual acuity (of three or more lines on an eye chart) than those receiving standard of care.

DME, a common complication of Diabetic Retinopathy (DR), is the leading cause of vision loss in people under the age of 65 in the United States with an estimated 500,000 treatable cases. DME is characterized by swelling of the retina and loss of vision. Currently the only FDA approved treatment is laser therapy in which holes are burned into the macula with a laser. This treatment is often ineffective or generally provides only temporary benefit. There are no approved drug therapies for the treatment of either DME or DR. Retisert for DME is surgically implanted into the eye and releases a constant amount of the drug, fluocinolone acetonide. Retisert is FDA approved for the treatment of posterior uveitis with a duration of 30 months and is licensed to Bausch & Lomb and co-promoted by Novartis.

Medidur is pSivida's next generation product. It is a tiny, injectable device that can release the same drug as Retisert. Unlike Retisert, which is surgically implanted, Medidur is injected into the eye during an office visit. Medidur is in Phase III clinical trials in DME in collaboration with Alimera Sciences Inc., a specialty pharmaceutical company focused on the ophthalmic industry.
"As Retisert and Medidur can deliver the same drug, at a similar rate, to the back of the eye, we hope the Medidur trials in DME show a very similar improvement in visual acuity to that shown in the Retisert DME trial. Medidur differs from Retisert in that it is a smaller device that can be inserted without the need for surgery," said Mr Gavin Rezos, CEO of pSivida Limited.

Results of the Bausch & Lomb study has shown that a statistically significant number of eyes treated with Retisert had an improvement of visual acuity of three or more lines on an eye chart compared to eyes receiving standard of care (28% versus 15%, p less than 0.05). Additionally, a statistically significant number of eyes treated with Retisert showed an improvement in their diabetic retinopathy severity score, a measure of the severity of their disease (13% versus 4% p less than 0.001). More eyes receiving Retisert also showed a reduction in their edema and there was also no evidence of edema in 58% of eyes receiving the implant versus 30% of eyes receiving standard of care (p less than 0.001).

Side-effects of Retisert in patients with DME were similar to those reported in patients with uveitis for which Retisert is approved. Of the patients with DME receiving Retisert, at three years 33% required an operation to relieve elevated intraocular pressure (IOP) and 95% required cataract surgery. Cataract surgery is a relatively uncomplicated and established procedure with a high success rate. The abstract (#5442) detailing the DME data is available on the website of the Association for Research in Vision and Ophthalmology http://www.arvo.org. The three year uveitis data is available at the same website (abstract #1523). Fuller data will be presented at the ARVO conference in May 2006.

pSivida receives royalties from sales of Retisert for chronic non-infectious posterior segment uveitis, a sight threatening condition that affects an estimated 175,000 people in the United States and an estimated 800,000 people worldwide. The product is presently priced at US$18,250 and is approved as a 30 month treatment. Covered in the United States by Medicare and Medicaid, Retisert is co-marketed in the United States by Bausch & Lomb and Novartis. In the event that Retisert is approved for DME and Bausch & Lomb decide to market Retisert for DME, then pSivida will receive royalty payments from Bausch & Lomb for Retisert sales for DME.