Medicago Reports Positive Phase I Results for its Avian Flu Pandemic Vaccine

Company's Results Amongst the Best for Influenza Vaccine Manufacturing Technologies

QUEBEC CITY, December 21 - Medicago Inc. (TSX-V: MDG) a biotechnology company focused on developing
highly effective and affordable vaccines based on proprietary manufacturing
technologies and Virus-Like Particles (VLPs), today reported positive interim
results from a Phase I human clinical trial with its H5N1 Avian Influenza
vaccine candidate ("H5N1 vaccine"). The vaccine was found to be safe, well
tolerated and also induced a solid immune response.

"We are very pleased with the results from this study. This trial was the
first ever clinical evaluation of a plant-based Influenza VLP vaccine and
shows that Medicago's vaccine is safe in humans," said Andy Sheldon,
President and CEO of Medicago. "We believe our novel vaccine candidate,
coupled with our rapid response and low cost manufacturing system offers a
preferred option to increase the speed of a public health response in the
event of a pandemic outbreak. Looking ahead, the successful completion of
this trial should enable us to formalize various partner agreements. It may
also allow us to access new sources of non-dilutive funding available through
U.S. grant programs and by organizations interested in funding the
development of better technologies for pandemic vaccine production."

The Phase I study was designed to investigate the safety of the Company's
H5N1 alum-adjuvanted pandemic vaccine candidate and to provide an initial
indication of the immune response. A total of 48 healthy volunteers between
the ages 18 to 60 received two doses of either Medicago's vaccine at doses of
5, 10 or 20 micrograms (mcg) or a placebo. No serious adverse events were
reported during the trial and the vaccine was found to be well tolerated at
all three dose levels. Local site reactions were mild and the incidence of
systemic side effects was comparable between the H5N1 vaccine groups and the
placebo. As planned in the initial design, adverse event monitoring will
continue for six months after administration of the second vaccine dose. The
trial was conducted at the Vaccine Evaluation Center of McGill University in
Montreal, Canada, under the supervision of Dr. Brian Ward.

Preliminary results showed that 81% of immunized subjects developed an
immune response against the H5N1 virus after the second immunization. A four-
fold increase in HI titers from baseline in 58% of subjects was observed in
the 20 mcg group. HI titers greater than 1:40 were developed in 50% of the
subjects in the 20 mcg group. The H5N1 vaccine also induced the production of
antibodies cross-reacting with two other strains of H5N1 Avian Influenza
suggesting Medicago's vaccine potential for cross-protection.

"Results at these lower dosage levels have not been reported for an H5N1
vaccine manufactured with a novel vaccine manufacturing technology," said
Nathalie Landry, VP Product Development of Medicago. "H5N1 vaccines are
poorly immunogenic in humans and are known to require repeated
administrations with an adjuvant to elicit an immune response at low doses."

Full results of this trial will be submitted for publication in a
scientific journal and will be available in the coming months. Based on these
results, Medicago will proceed with a Phase II clinical trial, expected to
commence during the first half of 2010.

About Medicago's pandemic flu vaccine candidate

Medicago's H5N1 vaccine candidate was formulated to protect against the
Indonesian influenza virus. It is manufactured in Nicotiana benthamiana, a
relative of the tobacco plant, using the Company's proprietary VLP
technology. VLPs may have several advantages over traditional flu vaccines.
They are made to look like a virus, allowing them to be recognized readily by
the body's immune system, however, they lack the core genetic material making
them non-infectious and unable to replicate. FDA-approved H5N1 influenza
vaccines in the United States require two 90-microgram doses, administered at
least four weeks apart to achieve appropriate level of antibodies in 44% of
vaccinated individuals. Because Medicago's technology requires the genetic
sequence of a viral strain and not the live influenza virus, vaccines can be
manufactured within four weeks of obtaining the genetic sequence of a
pandemic strain. This is in contrast with current manufacturing technologies
which rely on strain adaptation and can only deliver a vaccine six to nine
months after a pandemic is declared.

About Medicago

Medicago is committed to provide highly effective and affordable vaccines
based on proprietary Virus-Like Particle (VLP) and manufacturing
technologies. Medicago is developing VLP vaccines to protect against H5N1
pandemic influenza, using a transient expression system which produces
recombinant vaccine antigens in non-transgenic plants. This technology has
potential to offer advantages of speed and cost over competitive
technologies. It could deliver a vaccine for testing in about a month after
the identification and reception of genetic sequences from a pandemic strain.
This production time frame has the potential to allow vaccination of the
population before the first wave of a pandemic strikes and to supply large
volumes of vaccine antigens to the world market. Additional information about
Medicago is available at www.medicago.com.

Forward Looking Statements

This news release includes certain forward-looking statements that are
based upon current expectations, which involve risks and uncertainties
associated with Medicago's business and the environment in which the Company
operates. Any statements contained herein that are not statements of
historical facts may be deemed to be forward-looking, including those
identified by the expressions "anticipate", "believe", "plan", "estimate",
"expect", "intend", and similar expressions to the extent they relate to
Medicago or its management. The forward-looking statements are not historical
facts, but reflect Medicago's current expectations regarding future results
or events. These forward-looking statements are subject to a number of risks
and uncertainties that could cause actual results or events to differ
materially from current expectations, including the matters discussed under
"Risks Factors and Uncertainties" in Medicago's Annual Information Form filed
on March 25, 2009 with the regulatory authorities. Medicago assumes no
obligation to update the forward-looking statements, or to update the reasons
why actual results could differ from those reflected in the forward-looking
statements.

Neither TSX Venture Exchange nor its Regulation Services Provider (as
that term is defined in the policies of the TSX Venture Exchange) accepts
responsibility for the adequacy or accuracy of this release.

For further information: Medicago, Inc., Andy Sheldon, President and CEO,
+1-418-658-9393 x135; Medicago Inc., Pierre Labbé, Chief Financial Officer,
+1-418-658-9393 x135

For further information: Medicago, Inc., Andy Sheldon, President and CEO, +1-418-658-9393 x135; Medicago Inc., Pierre Labbé, Chief Financial Officer, +1-418-658-9393 x135