Newly Published Study Shows OPKO's siRNA Bevasiranib Is Taken Up by Target Tissues in the Eye

MIAMI, June 3 /PRNewswire-FirstCall/ -- OPKO Health, Inc. (Amex: OPK) today announced that a study published in the peer-reviewed journal Molecular Vision demonstrates that bevasiranib, its siRNA (small interfering RNA) agent is distributed throughout the eye, including extensive uptake into the retina. In two tissue distribution and pharmacokinetic studies in rabbits, results showed that bevasiranib was present in the retina and in targeted retinal pigment epithelium (RPE) cells following intravitreal injection. Bevasiranib is a gene-silencing agent designed to shut down the production of vascular endothelial growth factor (VEGF), a primary cause of the new blood vessel growth, or neovascularization, associated with vision loss in patients with wet age-related macular degeneration, or wet AMD. The efficacy and safety of bevasiranib are currently being assessed in the COBALT study, an international Phase III trial for the treatment of wet AMD.

"Importantly, these data indicate that following intravitreal injection, bevasiranib distributes to the ocular structures relevant to the VEGF-induced neovascularization associated with vision loss in wet AMD, and we believe this animal data provides support for the use of bevasiranib in our ongoing pivotal Phase III trial for the treatment of wet AMD," said Samuel Reich, Executive Vice President of OPKO Ophthalmics. "It is noteworthy that bevasiranib was distributed to the RPE cells, since we believe that even a fraction of the tissue-associated bevasiranib entering the RPE cell is likely to be effective in specifically suppressing VEGF production."

"Ocular biodistribution of bevasiranib following a single intravitreal injection to rabbit eyes," NS Dejneka, S Wan, OS Bond, DJ Kornbrust, SJ Reich, Molecular Vision, Volume 14, May 28, 2008

About OPKO Health, Inc.

Miami-based OPKO is a specialty healthcare company. Its lead investigational drug, the pioneering gene silencing agent bevasiranib, has entered a pivotal Phase III trial after successfully completing Phase II trials for wet age-related macular degeneration and diabetic macular edema. OPKO is developing a preclinical pipeline of novel agents for ophthalmic diseases, and it markets innovative diagnostic imaging systems that complement the company's therapeutic products. For more information visit the company's website at http://www.opko.com.

This press release contains "forward-looking statements," as that term is defined under the Private Securities Litigation Reform Act of 1995 (PSLRA), which statements may be identified by words such as "expects," "plans," "projects," "will," "may," "anticipates," "believes," "should," "intends," "estimates," and other words of similar meaning, including statements regarding the potential benefits and effectiveness of bevasiranib in suppressing the production of VEGF and reducing ocular neovascularization, our ability to establish OPKO's leadership position, our ability to aggressively engage in R&D activities and advance clinical testing of bevasiranib and our ability to develop a preclinical pipeline of novel agents for ophthalmic diseases, as well as other non-historical statements about our expectations, beliefs or intentions regarding our business, technologies and products, financial condition, strategies or prospects. Many factors could cause our actual activities or results to differ materially from the activities and results anticipated in forward-looking statements. These factors include those factors described in our filings with the Securities and Exchange Commission, as well as risks inherent in funding, developing and obtaining regulatory approvals of new, commercially-viable and competitive products and treatments, including the risks that enrollment of patients for the Phase III clinical trial for bevasiranib, may not be successful, that the Phase III clinical trial itself may not be completed on a timely basis or at all, that any of our compounds under development, including bevasiranib, may fail, may not achieve the expected results or effectiveness and may not generate data that would support the approval or marketing of products for the indications being studied or for other indications. In addition, forward-looking statements may also be adversely affected by general market factors, competitive product development, product availability, federal and state regulations and legislation, the regulatory process for new products and indications, manufacturing issues that may arise, patent positions and litigation, among other factors. The forward-looking statements contained in this press release speak only as of the date the statements were made, and we do not undertake any obligation to update forward-looking statements. We intend that all forward-looking statements be subject to the safe-harbor provisions of the PSLRA.

SOURCE OPKO Health, Inc.