MedImmune, Inc. (Nasdaq: MEDI) announced today that the U.S. Food and Drug Administration (FDA) has approved the company's new refrigerated formulation of FluMist(R) (Influenza Virus Vaccine Live, Intranasal) for use in helping to prevent influenza in healthy children and adults from 5 years to 49 years of age.

"Large and well-controlled clinical trials have shown FluMist to be an effective and well-tolerated option to help prevent influenza disease in healthy children and adults," stated Frank M. Malinoski, M.D., Ph.D., senior vice president, medical and scientific affairs. "We are confident that the approval of our refrigerated formulation for FluMist will encourage more healthcare providers to offer FluMist to their customers and patients. The new formulation can be conveniently stored in a standard refrigerator rather than frozen, as previously required. We recognize that the frozen storage presented difficulties for some physician practices as well as for providers who administer vaccine in places like schools, pharmacies and grocery stores, and we are confident that this improvement will enhance access to this important vaccine."

FluMist has been marketed in a frozen formulation since its original FDA approval in 2003, and millions of doses have been distributed and administered. The newly approved formulation of FluMist, known in clinical studies as CAIV-T (cold adapted influenza vaccine-trivalent), will be available for the 2007-2008 influenza season. Both formulations are free of preservatives, including thimerosal.

Next MedImmune Goal for FluMist: Expanding the Pediatric Label

To date, 42 clinical trials involving approximately 60,000 individuals have been conducted, including children as young as 6 weeks of age and adults up to 98 years of age. In a recently completed pivotal Phase 3 study involving approximately 8,500 children between 6 months and 59 months of age, FluMist demonstrated a statistically significant 55 percent relative reduction in the incidence of influenza illness caused by any influenza strain including both matched and mismatched strains when compared to the injectable influenza vaccine (TIV). This study was conducted during the 2004-2005 influenza season in the U.S., Europe and Asia and it was submitted in July 2006 to the FDA as the basis of MedImmune's request to expand the age indication for FluMist to include children as young as one year of age who do not have a history of wheezing or asthma.

Pending the FDA's approval of an expanded age indication, MedImmune plans to increase production of its new formulation of FluMist for the 2007-2008 season. MedImmune anticipates shipping its first doses in 2007 in time for physicians to start vaccinating patients as early as August.

About FluMist

FluMist is currently indicated for active immunization for the prevention of disease caused by influenza A and B viruses in healthy children and adolescents, 5 to 17 years of age, and healthy adults, 18 to 49 years of age. There are risks associated with all vaccines, including FluMist. As with any vaccine, FluMist does not protect 100 percent of individuals vaccinated and may not protect against viral strains not contained in the vaccine.

Under no circumstances should FluMist be administered as an injection (i.e. parenterally). FluMist is contraindicated in persons with hypersensitivity to any component of the vaccine, including eggs; in children and adolescents receiving aspirin therapy or aspirin-containing therapy; in individuals with a history of Guillain-Barre syndrome; and in individuals with known or suspected immune deficiency. The safety and efficacy of FluMist have not been established in pregnant women or for patients with chronic underlying medical conditions, including asthma or reactive airways disease; the vaccine should not be administered to these patients.

In randomized, placebo-controlled clinical trials of FluMist in its refrigerated and frozen formulations, the most common solicited adverse events in the indicated population (n=11,604) included runny nose/nasal congestion, sore throat, cough, irritability, headache, chills, vomiting, muscle aches, decreased appetite, abdominal pain, and decreased activity/feeling of tiredness/weakness.

For information for indications and usage, dosage and administration, and safety information, please see the current Prescribing Information at flumist/pdf/prescribinginfo.pdf, visit flumist, or call 1-877-633-4411 for additional information.

About MedImmune, Inc.

MedImmune strives to provide better medicines to patients, new medical options for physicians, rewarding careers to employees, and increased value to shareholders. Dedicated to advancing science and medicine to help people live better lives, the company is focused on the areas of infectious diseases, cancer and inflammatory diseases. With more than 2,500 employees worldwide, MedImmune is headquartered in Maryland. For more information, visit the company's website at medimmune/ .

This announcement contains, in addition to historical information, certain "forward-looking statements" regarding the potential prospects of FluMist and the results of clinical trials for CAIV-T. Such forward-looking statements are based on current expectations and involve inherent risks and uncertainties, including factors that could delay, divert or change current expectations and could cause actual outcomes and results to differ materially from current expectations. In addition to risks and uncertainties discussed in MedImmune's filings with the U.S. Securities and Exchange Commission, no assurance exists that FluMist will receive required regulatory approval for children 12 months to 59 months of age or that, even if regulatory approval is received, FluMist will be commercially successful. MedImmune undertakes no obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise except as may be required by applicable law or regulation.

MedImmune, Inc.
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