ThromboGenics and BioInvent Announce the Start of New Study of Novel Antibody Anti-Cancer Agent TB-403 (Anti-PlGF) by Partner Roche

Two New Studies Now Ongoing: Phase Ib/II in Patients With Aggressive Brain Tumour and Phase Ib in Primary Liver Cancer

LEUVEN, Belgium and LUND, Sweden, May 16, 2011 - ThromboGenics NV (Euronext Brussels: THR) and co-development partner
BioInvent International AB (OMXS: BINV) announce today that their partner
Roche (SIX: RO, ROG; OTCQX: RHHBY) has dosed the first patient in a Phase
Ib/II study with the novel antibody anti-cancer agent TB-403 (RG7334). The
trial is in patients with glioblastoma multiforme, the most common and
aggressive type of primary brain tumour in humans.

The multi-center, Phase Ib/II trial will examine the safety and clinical
effect of TB-403 in combination with Avastin(R) (bevacizumab) in patients
with recurrent glioblastoma. Secondary objectives include safety,
tolerability and pharmacokinetics of the combination. The trial will also
include an evaluation of candidate biomarkers. The study will recruit
approximately 100 patients.

The start of the Phase Ib/II glioblastoma study has triggered a EUR4
million milestone payment to ThromboGenics and BioInvent. This is the second
clinical milestone that they have received from Roche. The first milestone of
EUR10 million was paid last year when Roche initiated an imaging study in
patients with colorectal and ovarian cancer.

In March 2011, Roche initiated a Phase Ib study of TB-403 in
patients with primary liver cancer (hepatocellular carcinoma). This study
will determine the safety, tolerability and dosage of TB-403 in combination
with Nexavar(R) (sorafenib), as well as pharmacokinetics and
pharmacodynamics. The study will recruit 60-70 patients.

Dr Patrik De Haes, CEO of ThromboGenics, commented, "The start of these
trials reflects a great interest in evaluating TB-403, in combination with
more established oncology drugs, in a range of cancer indications. The
glioblastoma study, using TB-403 together with Avastin, is designed to find
better treatment options for patients with this very aggressive form of brain
cancer. I believe that these studies will confirm that the further
development of this novel selective anti-angiogenic antibody is warranted."

Svein Mathisen, CEO of BioInvent added, "We are very pleased that Roche
has decided to take TB-403 to the next stage of its development. We believe
that TB-403 could make a major contribution to the armamentarium used to
treat cancer. In glioblastoma, the medical need is significant and it is our
hope that this unique product candidate could improve the prospects for this
patient group whose current treatment options are very limited."

Notes to Editors:

About TB-403

The novel mechanism of action of TB-403 represents a potentially
promising cancer therapy. It is a humanized monoclonal antibody directed
towards placental growth factor (PIGF), expected to act by blocking the
formation of the new blood vessels that are required for tumor growth.
Preclinical exploration of PIGF biology suggests a role in tumor angiogenesis
and metastasis and a limited role in the maintenance of normal vasculature.
This mode of action could result in therapeutic benefit with an acceptable
side effect profile.

Two Phase I clinical trials have found that TB-403 was well tolerated
with no reported dose limited toxicity.

About ThromboGenics

ThromboGenics is a biopharmaceutical company focused on the discovery and
development of innovative medicines for the treatment of eye disease,
vascular disease and cancer. The Company's lead product ocriplasmin
(microplasmin) has completed two Phase III clinical trials for the
pharmacological treatment of symptomatic vitreomacular adhesion (sVMA).
Ocriplasmin is also being evaluated in Phase II clinical development for
additional vitreoretinal conditions. In addition, ThromboGenics is developing
novel antibody therapeutics in collaboration with BioInvent International;
these include TB-402 (anti-Factor VIII), a long acting anti-coagulant in
Phase II, and TB-403 (anti-PlGF) in Phase Ib/II for cancer in partnership
with Roche.

ThromboGenics is headquartered in Leuven, Belgium. The Company is listed
on NYSE Euronext Brussels under the symbol THR. More information is available
at www.thrombogenics.com.

About BioInvent

BioInvent International AB, listed on the NASDAQ OMX Stockholm (BINV), is
a research-based

pharmaceutical company that focuses on developing antibody drugs. The
Company currently has four clinical development projects within the areas of
thrombosis, cancer and atherosclerosis. The Company has signed various
strategic alliances to strengthen the product pipeline and increase the
likelihood of success. These partners include Genentech, Human Genome
Sciences, Roche and ThromboGenics.

The company's competitive position is underpinned by an in substance
patented antibody development platform. The scope and strength of this
platform is also utilised by partners, such as Bayer HealthCare, Daiichi
Sankyo, Mitsubishi Tanabe, UCB and XOMA. More information is available at
www.bioinvent.com.

Legal disclaimer

This press release contains statements about the future, consisting of
subjective assumptions and forecasts for future scenarios. Predictions for
the future only apply as of the date they are made and are, by their very
nature, in the same way as research and development work in the biotech
segment, associated with risk and uncertainty. With this in mind, the actual
outcome may deviate significantly from the scenarios described in this press
release.

Information disclosed in this press release is provided herein
pursuant to the Swedish Securities Markets Act and/or the Swedish Financial
Instruments Trading Act. The information was submitted for publication at
7.30 a.m. CET, on X February, 2011.

    For further information, please contact:

    ThromboGenics NV

    Dr. Patrik De Haes
    CEO
    Tel: +32(0)16-75-13-10
    E-mail: patrik.dehaes@thrombogenics.com 

    Dr. Steve Pakola
    CMO
    Tel: +1(212)201-0920
    E-mail: steve.pakola@thrombogenics.com

    Citigate Dewe Rogerson
    David Dible, Nina Enegren, Sita Shah
    Tel: +44(0)207-638-95-71
    E-mail: nina.enegren@citigatedr.co.uk

    BioInvent International AB

    Svein Mathisen
    President & CEO
    Tel:    +46(0)46-286-85-67
    Mobile: +46(0)708-97-82-13
    E-mail: svein.mathisen@bioinvent.com 

    Cristina Glad
    Executive Vice President
    Tel: +46 (0)46-286 85 51
    Mobile: +46 (0)708-16 85 70
    E-mail: cristina.glad@bioinvent.com

    College Hill (media enquiries)
    Melanie Toyne Sewell, Anastasios Koutsos
    Tel: +44(0)20-7866-7856
    Rebecca Skye Dietrich
    Tel: +1(857)241-0795
    E-mail: bioinvent@collegehill.com

    ThromboGenics NV
    Gaston Geenslaan 1
    B-3001 Leuven
    Belgium
    Tel: +32(0)16-75-13-10
    www.thrombogenics.com 

    BioInvent International AB (publ)
    Co. reg. No. 556537-7263,
    Address: Solvegatan 41
    Mailing address: SE-223 70 LUND
    Tel: +46(0)46-286-85-50
    info@bioinvent.com
    www.bioinvent.com

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