Medimmune Completes Enrollment in Phase 3 Study Comparing Next-Generation, Intranasal Influenza Vaccine to Injectable inFluenza Vaccine

GAITHERSBURG, Md. -- MedImmune, Inc.

announced today that it has completed enrolling nearly 8,500

children in a pivotal Phase 3 trial approximately one week after initiating

the study.  The trial is designed to compare the next-generation,

refrigerator-stable intranasal influenza vaccine, known as CAIV-T (cold

adapted intranasal influenza vaccine, trivalent), to the injectable influenza

vaccine.  MedImmune is developing CAIV-T as a potential improvement over its

currently marketed frozen influenza vaccine, FluMist (Influenza Virus Vaccine

Live, Intranasal). 

MedImmune also announced today that it has begun enrolling

patients in a Phase 1/2 study comparing the safety and efficacy of FluMist to

the injectable influenza vaccine in children infected with HIV.

"To have enrolled nearly 8,500 children in a pivotal Phase 3 clinical

trial in one week's time is a great accomplishment," commented Dr. Robert

Walker, senior director of clinical research and the project's director,

"because it allows all children in the study to receive their first dose of

vaccine before the influenza season starts in earnest.  This could not have

been achieved without the tremendous cooperation of parents and children

involved in the study, as well as the incredible effort of hundreds of

participating investigational physicians, nurses and their dedicated staffs.

Our hope is that the result of our combined activities will show that CAIV-T

may offer an improved influenza vaccination strategy with an acceptable safety

profile for young children."

MedImmune's pivotal Phase 3 trial is a randomized, double-blind study

designed to assess the comparable safety and relative efficacy of CAIV-T and

the injectable influenza vaccine during the 2004/2005 influenza season.  The

study, being conducted at 249 sites in 16 countries in the Northern

Hemisphere, has enrolled 8,492 children between the ages of 6 months through

59 months.  Participants have been randomized one-to-one to receive either

CAIV-T or the injectable influenza vaccine.  A placebo mist and injection will

be used to preserve the double-blind design of the study.  Participants will

be followed throughout the influenza season and evaluated to identify

illnesses caused by influenza virus.

 This Phase 3 trial is one of eight clinical trials currently being

conducted by MedImmune with either FluMist or CAIV-T that are building upon

data collected from a large number of previously completed studies.  Twenty-

one clinical trials involving approximately 30,000 subjects have already been

completed for FluMist, while an additional 21 trials involving

approximately another 34,000 subjects have already been completed for CAIV-T.

MedImmune has entered into a collaboration with the Pediatric AIDS

Clinical Trials Group (PACTG) to compare FluMist to the injectable influenza

vaccine in HIV-infected children.  This Phase 1/2 trial is a randomized, open

label study designed to evaluate the safety, immunogenicity and vaccine virus

shedding in HIV-infected children.  The study will enroll approximately 300

HIV-infected children from 5 to 18 years of age at approximately 50

participating PACTG sites in the United States.  Each participant will be

followed for six months after dosing.

 In a previous clinical study, FluMist was safely administered to 24 HIV-

infected children aged 1 to 8 years.  Signs and symptoms in the HIV-infected

children in this study were similar to those seen in healthy children who have

received FluMist, and there were no vaccine-related serious adverse events.

Similar results were obtained in a study involving 57 HIV-infected adults.

FluMist is the first live, attenuated influenza vaccine 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.

For the 2004-2005 influenza season, the CDC has encouraged the use of

intranasally administered, live, attenuated influenza vaccine (FluMist), if

available, for healthy, non-pregnant individuals ages 5 to 49 years, including

healthcare workers (except those who care for severely immunocompromised

patients in special care units) and individuals caring for children younger

than six months.

There are risks associated with all vaccines, including FluMist.  FluMist

does not protect 100-percent of individuals vaccinated, or may not protect

against viral strains not represented in the vaccine.  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. 

Source:  MedImmune, Inc.