VEGF Trap-Eye Phase 2 Wet AMD Results Reported at ARVO Annual Meeting.

Average Vision Gain of More Than 10 Letters at 12 Weeks in Highest Monthly Dose Group

Single Dose Results in Average Vision Gain at 12 Weeks

Phase 3 wet AMD Program to Begin in the Third Quarter of 2007

FORT LAUDERDALE, Fla. -- Regeneron Pharmaceuticals, Inc. (Nasdaq: REGN) today announced positive results from several studies evaluating the VEGF Trap-Eye in the neovascular form of age-related macular degeneration (wet AMD) and diabetic macular edema (DME). These findings were presented this week at the annual meeting of the Association for Research in Vision and Ophthalmology (ARVO). The data reported at the meeting from a pre-planned interim analysis of a Phase 2 randomized study of the VEGF Trap-Eye in patients with wet AMD and a Phase 1 DME trial are available on the Regeneron website (www.regeneron.com on the Events page, under the Investor Relations heading).

"We are very encouraged by the preliminary observation in the Phase 2 wet AMD trial that the most intense dosing regimen studied, 2 milligrams delivered by intravitreal injection every 4 weeks, resulted in an average gain of more than 10 letters after 12 weeks of treatment," said George D. Yancopoulos, M.D., Ph.D., President of Regeneron Research Laboratories. "Perhaps equally important is that after receiving only a single dose of the VEGF Trap-Eye, patients on average had an improvement in the number of letters read both 8 and 12 weeks after treatment. Although significantly more clinical testing is required, the VEGF Trap-Eye may offer the potential to improve vision in patients with wet AMD with a regular dosing regimen that is less frequent than monthly."

Regeneron and Bayer HealthCare AG plan to initiate the VEGF Trap-Eye Phase 3 program in wet AMD in the third quarter of 2007. In the first Phase 3 trial, the companies currently plan to evaluate the VEGF Trap-Eye using 4 and 8 week dosing intervals in direct comparison with ranibizumab (Lucentis([R]), a registered trademark of Genentech, Inc.) administered every 4 weeks according to its label. The companies are collaborating on the global development of the VEGF Trap-Eye for the treatment of wet AMD, diabetic eye diseases, and other eye diseases and disorders. Bayer HealthCare AG and Regeneron will jointly commercialize the VEGF Trap-Eye outside the United States, and Regeneron maintains exclusive rights in the United States.

In the Phase 2 wet AMD trial, data were presented from a pre-planned interim analysis of the first 78 patients who completed 12 weeks of the study. The randomized, multi-center trial involves 150 patients who were randomized to 5 groups and treated with the VEGF Trap-Eye in one eye. Two groups received either 0.5 or 2.0 milligrams (mg) of VEGF Trap-Eye administered every 4 weeks, and three groups received a single dose of 0.5, 2.0, or 4.0 mg of VEGF Trap-Eye. Patients were monitored for safety, retinal thickness, and visual acuity over 12 weeks. The VEGF Trap-Eye met its primary endpoint of a statistically significant reduction in retinal thickness after 12 weeks compared with baseline (all groups combined, decrease of 135 microns, p < 0.0001). Mean change in visual acuity, a key secondary endpoint of the study, also demonstrated a statistically significant improvement (all groups combined, increase of 5.9 letters, p < 0.0001). There were no drug-related serious adverse events, and treatment with the VEGF Trap-Eye was generally well-tolerated. The most common adverse events were those typically associated with intravitreal injections. Interim data for all dose groups were presented at the ARVO meeting. The Phase 2 wet AMD study is now fully enrolled and results for all patients will be presented at a future scientific meeting.

Encouraging results were also presented from a Phase 1 study of VEGF Trap-Eye in DME. In this open-label safety study, the VEGF Trap-Eye was administered as a single 4.0 mg intravitreal injection to 5 patients with longstanding diabetes and multiple prior treatments for DME. The single injection resulted in a marked decrease in mean central retinal thickness and mean macular volume throughout the 6 week observation period. The VEGF Trap-Eye was generally well tolerated, and there were no drug-related serious adverse events. Adverse events were mostly related to the injection procedure.

About the VEGF Trap-Eye

Vascular endothelial growth factor (VEGF) is a naturally occurring protein in the body whose normal role is to trigger formation of new blood vessels (angiogenesis) to support the growth of the body's tissues and organs. It has also been associated with the abnormal growth and fragility of new blood vessels in the eye, which lead to the development of wet AMD. The VEGF Trap-Eye is a fully human, soluble VEGF receptor fusion protein that binds all forms of VEGF-A along with the related placental growth factor (PlGF). The VEGF Trap-Eye is a specific and highly potent blocker of these growth factors. Blockade of VEGF, which can prevent abnormal blood vessel formation and vascular leak, has proven beneficial in the treatment of wet AMD. Blocking VEGF has been shown to be effective in patients with wet AMD; and a VEGF inhibitor, ranibizumab, has been approved for treatment of patients with this condition.

About AMD

Age-related macular degeneration (AMD) is a leading cause of acquired blindness. Patients with this condition can experience a loss of vision due to the development of abnormal, fragile blood vessels in the back of the eye. A particular type of AMD, called wet AMD, accounts for approximately 90% of AMD-related blindness. Wet AMD is the leading cause of blindness for people over the age of 65 in the U.S. and Europe.

Macular degeneration is diagnosed as either dry (nonexudative) or wet (exudative). In wet AMD, new blood vessels grow beneath the retina and leak blood and fluid. This leakage causes disruption and dysfunction of the retina creating blind spots in central vision, and it can account for blindness in wet AMD patients.

About DME

Diabetic Macular Edema (DME) is the most prevalent cause of moderate vision loss in patients with diabetes. DME is a common complication of Diabetic Retinopathy (DR), a disease affecting the blood vessels of the retina. A leading cause of blindness in younger adults (under 50), DME occurs when fluid leaks into the center of the macula, the light-sensitive part of the retina responsible for sharp, direct vision. Fluid in the macula can cause severe vision loss or blindness.

Approximately 500,000 Americans currently suffer from DME, with 75,000 new cases arising each year. According to the American Diabetes Association, more than 18 million Americans currently suffer from diabetes and many other people are at risk for developing diabetes. With the incidence of diabetes steadily climbing, it is projected that up to 10 percent of all patients with diabetes will develop DME during their lifetime.

About Regeneron Pharmaceuticals

Regeneron is a biopharmaceutical company that discovers, develops, and intends to commercialize therapeutic medicines for the treatment of serious medical conditions. Regeneron has therapeutic candidates for the potential treatment of cancer, eye diseases, and inflammatory diseases and has preclinical programs in other diseases and disorders.

This news release discusses historical information and includes forward-looking statements about Regeneron and its products, programs, finances, and business, all of which involve a number of risks and uncertainties, such as risks associated with preclinical and clinical development of our drug candidates, determinations by regulatory and administrative governmental authorities which may delay or restrict our ability to continue to develop or commercialize our drug candidates, competing drugs that are superior to our product candidates, unanticipated expenses, the availability and cost of capital, the costs of developing, producing, and selling products, the potential for any collaboration agreement, including our agreements with the sanofi-aventis Group and Bayer HealthCare, to be canceled or to terminate without any product success, risks associated with third party intellectual property, and other material risks. A more complete description of these and other material risks can be found in Regeneron's filings with the United States Securities and Exchange Commission (SEC), including its Form 10-Q for the quarter ended March 31, 2007. Regeneron does not undertake any obligation to update publicly any forward-looking statement, whether as a result of new information, future events, or otherwise unless required by law.

Additional information about Regeneron and recent news releases are available on Regeneron's worldwide web site at www.regeneron.com