- Process Enhances Efficiency and Reliability in Producing Seasonal and
Pandemic Influenza Vaccines -
GAITHERSBURG, Md., July 6 /PRNewswire-FirstCall/ -- MedImmune, Inc.
(Nasdaq: MEDI) announced today that the U.S. Food and Drug Administration
(FDA) has approved the company's supplemental biologics license application
(sBLA) to use reverse genetics technology to construct new vaccine strains to
produce seasonal influenza vaccines, including FluMist (Influenza Virus
Vaccine Live, Intranasal) and the next-generation, refrigerator-stable
formulation, CAIV-T (cold adapted intranasal vaccine -- trivalent). Creation
of new vaccine strains is the first step (and often a production-limiting one)
in the influenza vaccine manufacturing process. Use of reverse genetics (also
known as "plasmid rescue") technology enhances the safety, specificity,
reliability and efficiency with which new vaccine strains can be produced.
"Reverse genetics represents an important breakthrough in commercial
influenza vaccine processes by improving the efficiency of producing new
influenza vaccine strains on an annual basis," said George W. Kemble, Ph.D.,
vice president, research and development, vaccines. "This technology enables
scientists to replace cumbersome seasonal vaccine strain development methods
that were created in the 1960s with modern techniques, which should allow us
to accelerate the availability of influenza vaccines to the public.
"For producing pandemic influenza vaccine seeds, reverse genetics has the
added benefit of allowing scientists to remove potentially pathogenic portions
of the virus, thereby creating a safer production process for the vaccines,"
Dr. Kemble commented further.
Toward this end, MedImmune has already begun applying its plasmid rescue
technology to pandemic research efforts. Last month, the National Institutes
of Health (NIH) began enrolling participants in a Phase 1 study of an
intranasal H5N1 influenza vaccine candidate based on MedImmune's live,
attenuated vaccine technology, which also utilized reverse genetics
technology. Investigators at MedImmune and Johns Hopkins Bloomberg School of
Public Health Center for Immunization Research, where the study is being
conducted, are hopeful that a live, attenuated intranasal influenza vaccine
would be as effective against potential pandemic A strains as it has been
shown to be against seasonal matched and mismatched A strains of influenza.
Most influenza vaccine manufacturing companies and governmental agencies
are now using reverse genetics technology in their development of pandemic
vaccine candidates because it allows them to avoid working directly with the
infectious, circulating pandemic strains. As the owner or exclusive licensee
of the key patent estates for use of the reverse genetics technology in human
influenza vaccines, MedImmune remains committed to making sure that the
technology is accessible to government institutions and industry
manufacturers. As such, the company has offered other influenza vaccine
manufacturers non-exclusive licenses to this intellectual property estate for
use in manufacturing seasonal or pandemic vaccines.
MedImmune's Commitment to Delivering Influenza Vaccines to the Public
As the manufacturer of FluMist, the first major innovation in influenza
vaccine technology in more than 50 years, MedImmune continues to expand upon
its commitment to ensure the nation is adequately protected against seasonal
and pandemic influenza by using the latest in scientific and medical
advancements. In addition to the activities described above, the company also
recently received a $170-million contract from the U.S. Health and Human
Services Department to expedite the development of cell culture-based
production of its influenza vaccine. Further, the company also recently
submitted its first lots of commercial FluMist for the 2006-2007 influenza
season to the FDA for approval and release. The company expects to have all
lots approved and released for commercial sale by the first week in September.
Should all things continue on track, MedImmune anticipates shipping its first
doses of FluMist for the upcoming season to customers by the end of July 2006.
FluMist is 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. Like any vaccine, FluMist
does not protect 100 percent of individuals vaccinated. In studies of people
between the ages of 5 and 49 years, runny nose was the most commonly reported
side effect. Other common side effects included various cold-like symptoms,
such as headache, cough, sore throat, tiredness/weakness, irritability, and
FluMist should not be used, under any circumstances, in anyone with an
allergy to any part of the vaccine, including eggs; in children and
adolescents receiving aspirin therapy; in people who have a history of
Guillain-Barre syndrome; and in people with known or suspected immune system
problems. Pregnant women and people with certain medical conditions, asthma,
or reactive airways disease should not get FluMist.
Please see the Prescribing Information at
http://www.flumist.com/pdf/prescribinginfo.pdf, visit http://www.flumist.com ,
or call 1-877-633-4411 for additional information.
CAIV-T is an investigational intranasal, cold-adapted trivalent influenza
vaccine. It is the next-generation, refrigerator-stable formulation of
FluMist, which is a frozen, live attenuated cold-adapted trivalent influenza
vaccine. To date, the safety, tolerability and efficacy of CAIV-T has been
studied in both healthy and at-risk populations between the ages of 6 weeks
and 98 years.
On May 1, 2006 at the Pediatric Academic Societies' annual meeting,
MedImmune presented its pivotal Phase 3 study for CAIV-T, entitled,
"Comparison of the Efficacy and Safety of Cold-Adapted Influenza Vaccine,
Trivalent With Trivalent Inactivated Influenza Vaccine in Young Children 5 to
59 Months of Age." The study included 8,475 children at 249 sites in 16
countries in North America, Europe, the Middle East and Asia. Study
participants were randomized one-to-one to receive either CAIV-T or the flu
shot during the 2004-2005 influenza season. Each participant also received a
placebo nasal spray or placebo injection to preserve the double-blind design
of the study. Participants were followed through the influenza season and
evaluated to identify illnesses caused by influenza virus. The trial included
more than 6,300 previously unvaccinated children with nearly 50 percent of
those children less than 2 years of age.
The results of this trial showed that CAIV-T was 55 percent more effective
than the trivalent injectable inactivated influenza vaccine (TIV) in reducing
influenza illness caused by any influenza strain in children 6 months to 59
months of age, including both matched and mismatched strains. The influenza
attack rate was 8.6 percent for study participants receiving the flu shot
compared to 3.9 percent for those who received CAIV-T (P <0.001). Against
matched strains alone, CAIV-T was 44 percent more effective than the flu shot
(attack rates: TIV = 2.4 percent, CAIV-T = 1.4 percent; P<0.001). In this
study, CAIV-T also appeared to be 89 percent more effective than the flu shot
in reducing influenza illness caused by the matched H1N1 A strain (attack
rates: TIV = 0.7 percent, CAIV-T = 0.1 percent; P<0.001) and 79 percent more
effective than the flu shot against the circulating mismatched H3N2 A strain
(attack rates: TIV = 4.5 percent, CAIV-T = 1.0 percent; P<0.001). There were
no cultures of mismatched H1N1 strains or matched H3N2 strains detected in the
trial. While there were 16-percent fewer children with illnesses associated
with B strains in the CAIV-T group compared to TIV (attack rates: TIV= 3.5
percent, CAIV-T = 3.0 percent), this difference was not statistically
In the study, the overall incidence of adverse events and serious adverse
events was similar in both groups except for a higher incidence of runny nose
and nasal congestion in CAIV-T recipients (2.5 - 5.6 percent increase) and a
higher incidence of injection site reactions in those receiving the flu shot
(3.6 - 7.6 percent increase). There were no significant differences through
the whole study period for all reported wheezing or for medically significant
wheezing (MSW), a pre-specified safety endpoint. Previously unvaccinated
children between 6 and 23 months of age had a small but statistically
significant increase in MSW at 42 days following their first dose (2.0 percent
for TIV vs. 3.2 percent for CAIV-T). Statistically significant differences
were not seen beyond 42 days after this first dose nor at any time after the
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 2,300 employees worldwide,
MedImmune is headquartered in Maryland. For more information, visit the
company's website at http://www.medimmune.com .
This announcement contains, in addition to historical information, certain
forward-looking statements that involve risks and uncertainties, in
particular, related to the research and development of potential influenza
vaccines. Such statements reflect management's current views and are based on
certain assumptions. Actual results could differ materially from those
currently anticipated as a result of a number of factors, including risks and
uncertainties discussed in MedImmune's filings with the U.S. Securities and
Exchange Commission. There can be no assurance that such development efforts
will succeed, that such products will receive required regulatory clearance or
that, even if such regulatory clearance is received, such products will
ultimately achieve commercial success.
SOURCE MedImmune, Inc.
CONTACT: Media: Clarencia Stephen, +1-301-398-4073, or Jamie Lacey, +1-
301-398-4035, Investors: Peter Vozzo, +1-301-398-4358, all of MedImmune, Inc.