Crescendo Biologics Extends IP Protection for Mouse Knock Out Technology

CAMBRIDGE, England, October 5, 2012 /PRNewswire/ –

Crescendo Biologics Limited (Crescendo) today announces it has received Notice of
Allowance of US 12/476,087 (a continuation of its granted patent US 7,541,513) which
covers mice in which the endogenous immunoglobulin lambda light chain locus is
functionally deleted.

This further extends coverage of the core Crescendo patent family which includes the
European patent EP1399559 (inventors: Brueggemann et al.) which was originally granted on
30th April 2008 to the Babraham Institute and was subsequently assigned to Crescendo. All
the key claims of EP1399559 were upheld by the Opposition Division on 4th April 2011.

Crescendo has already made use of its ability to knock out lambda light chain to
generate proprietary ‘triple knockout’ mice that have the immunoglobulin heavy chain,
kappa light chain and lambda light chain loci all functionally deleted. This is a
significant advance over previous knockout mice which retain intact lambda light chain.

Knockout of lambda light chain expression, in addition to knockout of heavy chain and
kappa light chain, is important for the efficient generation of human heavy chain
antibodies in a transgenic mouse. Therefore the triple knock out background is core to
Crescendo’s mouse platform which provides fully-human, in vivo-matured VH fragments, and
will be used in the development of differentiated products for the company’s in-house
pipeline and for partnering.

About Crescendo Biologics Ltd

Crescendo Biologics is building a pipeline of novel medicines based on its highly
innovative VH antibody fragment platform through both in-house development and strategic
partnerships. Crescendo’s proprietary VH technology produces human heavy chain-only
antibodies in transgenic mice providing a unique source of fully human VH fragments that
have matured in vivo to have high affinity, stability and solubility. VH fragments are the
smallest antibody fragments that retain binding affinity and specificity offering the
potential to generate novel products with improved drug-like properties and able to
address unmet medical needs.

Crescendo’s technologies were invented by scientists at the Babraham Institute,
Cambridge (UK). The company has raised funding totalling GBP7.7 million from an investment
consortium led by Sofinnova Partners with Avlar BioVentures, Babraham Bioscience
Technologies, and the Rainbow Seed Fund.

http://www.crescendobiologics.com

        Contacts

        Mike Romanos/Amanda Bettison
        Crescendo Biologics
        Tel: +44(0)1223-497140
        Email: mromanos/abettison@crescendobiologics.com

        Chris Gardner
        Citigate Dewe Rogerson
        Tel: +44(0)207-638-9571
        Email: chris.gardner@citigatedr.co.uk

SOURCE Crescendo Biologics Limited