Xencor Licenses Xtend™ Therapeutic Protein Half-life Extension Technology to CSL

 Xencor Licenses Xtend™ Therapeutic Protein Half-life Extension Technology to
                                     CSL

PR Newswire

MONROVIA, Calif. and MELBOURNE, Australia, April 16, 2013

MONROVIA, Calif. and MELBOURNE, Australia, April 16, 2013 /PRNewswire/ --
Xencor, Inc. announced today that Xencor and CSL Limited have entered into a
technology license agreement to provide CSL access to Xencor's Xtend
technology to optimize the performance of CSL's monoclonal antibodies.

Under the agreement CSL will be granted an exclusive license to utilize
Xencor's proprietary Xtend™ half-life extension technology in its program
against an undisclosed target. Xencor will receive an upfront payment and is
eligible to receive from CSL preclinical, clinical, regulatory and sales
milestone payments, as well as royalties on product sales.

"CSL's selection of Xencor's technology reflects the significant interest we
have seen in the use of our Xtend platform for enhancing next-generation
protein and antibody drug candidates," said Bassil Dahiyat, Ph.D., Xencor's
chief executive officer. "This technology offers our partners an opportunity
to create truly best-in-class therapeutics."

Xencor's Xtend technology dramatically improves the pharmacokinetic profile of
protein drug candidates while introducing only very subtle changes to the
protein sequence.

"Incorporating Xencor's Xtend technology into CSL's drug development aligns
with our approach of applying breakthrough science to the development of
therapeutics for life-threatening conditions," said Andrew Nash, Ph.D., senior
vice president of research of CSL. "We are committed to developing the highest
quality treatments for the patients who need them."

About Xtend™ technology
Xencor's proprietary antibody technology platform provides a validated
solution to enhancing the serum half-life of immunoglobulin molecules.Using
its proprietary series of antibody Fc variants, antibody half-life can be
readily prolonged to enhance performance in a number of different therapeutic
indications. By prolonging the serum half-life of antibody drug molecules the
opportunity arises to address chronic indications with an antibody drug
product that potentially i) enhances drug exposure and patient responses, ii)
is administered at more than monthly intervals, greatly enhancing patient
convenience, reducing administration costs and improving market positioning,
and iii) has a reduced dose required to maintain effective drug levels,
potentially improving the cost, profitability and capital expense profile of
the product.

About Xencor, Inc.
Xencor, Inc. engineers superior biotherapeutics using its proprietary Protein
Design Automation® technology platform, and is a leader in the field of
antibody engineering to significantly improve antibody half-life,
immune-regulatory function and potency. The company is advancing multiple
XmAb® antibody drug candidates in the clinic, including XmAb®5871 targeting
CD32b and CD19 for autoimmune diseases, and an anti-CD30 candidate XmAb®2513
for the treatment of Hodgkin's lymphoma. Xencor is also advancing a portfolio
of biosuperior versions of blockbuster antibody drugs engineered for superior
half-life and dosing schedule. Xencor has entered into multiple partnerships
with industry leaders such as Amgen, Pfizer, Janssen, MorphoSys, Boehringer
Ingelheim, CSL Ltd. and Human Genome Sciences. In these partnerships Xencor is
applying its suite of proprietary antibody Fc domains to improve antibody drug
candidates for traits such as sustained half-life and/or potency. For more
information, please visit www.xencor.com.

About CSL
Headquartered in Melbourne, Australia, CSL Limited is a global
biopharmaceutical company that develops, manufactures and markets biotherapies
to prevent and treat rare and serious human diseases. With major facilities in
Australia, Germany, Switzerland and the US, CSL employs over 11,000 people in
more than 27 countries. For more information visit www.csl.com.au.

SOURCE Xencor, Inc.

Website: http://www.xencor.com
Website: http://www.csl.com.au
Contact: Heidi Chokeir, Ph.D., Canale Communications for Xencor, 619-849-5377,
heidi@canalecomm.com