Plant Bioscience Ltd transfers control of Hypertrans® plant-based biologics and vaccines expression technology to Leaf Expression Systems Ltd

14 May 2019: Norwich Plant Bioscience Ltd (PBL) and Leaf Expression Systems Ltd (Leaf) are delighted to announce a further development in their relationship, with PBL granting Leaf the exclusive rights to sub-license the Hypertrans® transient expression system, the core technology underpinning Leaf’s biologics and vaccines contract development and manufacturing services business. Apart from rights previously granted to PBL’s pre-existing licensees, this effectively transfers to Leaf full control of the Hypertrans® technology and associated patented intellectual property. This extension of Leaf’s rights will ensure that Leaf’s clients are able to use Hypertrans® for the manufacture of their products in multiple geographical locations to meet the needs of individual markets and to enable clients to take advantage of lower manufacturing costs in some of these markets.

Leaf’s CEO Simon Saxby commented “I am delighted that we have strengthened our relationship with PBL and that we can now offer our clients the assurances they need in order to plan for scale up manufacture using Hypertrans® in the locations that are most appropriate for the target indications of their new biologic drugs or vaccines”.
PBL’s Managing Director Dr Jan Chojecki added “Leaf has been outstandingly successful in establishing its technical operations and developing its customer base and partnering activity. Now is the time to put Leaf fully in the driving seat with regard to this important and proprietary intellectual property asset developed originally by Professor George Lomonossoff at the John Innes Centre”.

For further information, contact:
Polly Ferris, Marketing & Communications Officer.
T: 01603 859 298

Notes to editors:

About Leaf Expression Systems

Leaf Expression Systems is a contract development and manufacturing business specialising in plant-based expression and production of proteins, vaccines and complex natural products for research and commercial applications. It uses Hypertrans®, the proprietary transient expression technology, which was originally developed by Professor George Lomonossoff of the John Innes Centre.

The Hypertrans® system allows for the rapid simultaneous production of multiple gene products in a controlled and coordinated manner within the tissues of plants. Using gene synthesis and modular vectors, new products such as vaccines, antibodies or enzymes can be produced at speed and on a large scale, so it is well suited to be able to rapidly respond to emergencies like pandemics.

Leaf Expression Systems is based in a purpose-built, state-of-the-art facility on Norwich Research Park, that boasts of four environmentally controlled growing rooms, plant potting areas, a plant inoculation area, microbiology/molecular biology labs, protein purification and natural product processing facilities.

About PBL
PBL ( is the intellectual property management and technology commercialization company of the John Innes Centre and others.

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