More than 300 million doses of seasonal influenza vaccine are produced each year globally, leaving a considerable shortfall in the event of a pandemic influenza outbreak. A powerful adjuvant such as CoVaccine HT™ may reduce the amount of antigen required in a pandemic influenza vaccine, enabling rapid, large scale production in the event of a pandemic influenza outbreak and for planned stockpiling. In addition, the CoVaccine HT™ adjuvant may increase the potency of a seasonal influenza vaccine for elderly people with impaired immune systems.

The licensing agreement gives Nobilon the exclusive global rights, excluding the US, to develop, manufacture and commercialize two new influenza vaccines containing CoVaccine HT™. Protherics will receive an upfront payment from Nobilon on signing the agreement. Protherics is also entitled to receive success related milestone payments and royalty payments on net sales by Nobilon.

Also announced today, Nobilon and a consortium of leading European vaccine experts has received a €3.5 million grant to help fund the development of a pandemic influenza vaccine containing CoVaccine HT.

Han van den Bosch, director Research and Development of Nobilon commented: "We are delighted to have gained exclusive access to CoVaccine HT, a promising new adjuvant from Protherics, for use in our flu vaccines. The very encouraging results in preclinical experiments using Nobilon's influenza antigen produced by cell culture and Protherics' CoVaccine HT adjuvant, justifies further clinical development."

Andrew Heath, Chief Executive of Protherics commented: "The agreement with Nobilon today supports our excitement about the prospects for our CoVaccine HT adjuvant, which we are also incorporating in our Angiotensin Therapeutic Vaccine. We also have considerable interest from other external parties to use our adjuvant in their vaccines across a range of other potential indications."

About the CoVaccine HT™ Adjuvant
An adjuvant is a substance which enhances the immune response and so helps maximise the production of antibodies. The CoVaccine HT™ adjuvant is a sucrose fatty acid sulphate ester that increases both humoral and cell-mediated immune responses to experimental vaccines following intramuscular administration. In nonclinical studies, the adjuvant has been well-tolerated with no limiting local toxicity, and has produced encouraging immune responses.

About Protherics
Protherics (LSE: PTI, NASDAQ: PTIL) is a leading biopharmaceutical company focused on the development, manufacture and marketing of specialised products for critical care and cancer.

Protherics has developed and manufactures two critical care products currently sold in the US: CroFab™, a pit viper antivenom and DigiFab™, a digoxin antidote. The Company's strategy is to use the revenues generated from its marketed and out-licensed products to help fund the advancement of its broad, late stage pipeline.

Protherics has two major development opportunities in its critical care portfolio. CytoFab™ is being developed by AstraZeneca, for the treatment of severe sepsis, following a major £195 million (more than $340 million) licensing deal in December 2005. An additional, expanded phase II programme is planned to start in the second half of 2007. In addition, Protherics is currently undertaking a phase IIb study with Digoxin Immune Fab for the treatment of pre-eclampsia. This study is expected to report in the first half of 2008.

Protherics has a pipeline of four novel cancer products in clinical development, and intends to undertake the sales and marketing of these products in the US or the EU. Protherics is preparing to resubmit a BLA for Voraxaze™, an adjunct to high dose methotrexate therapy, under a rolling submission in the US starting in early 2008.

Protherics has a strong cash position, with unaudited cash balances at 30 June 2007 of £45m. With headquarters in London, the Company has approximately 270 employees across its operations in the UK, US and Australia.

For further information, visit www.protherics.com.

About Nobilon
Nobilon International BV, part of Organon, a biopharmaceutical business unit of Akzo Nobel, was founded in 2003. It has production and R&D facilities in Boxmeer and Oss, the Netherlands. The biotechnology company is dedicated to develop, produce and market human vaccines against infectious diseases, building on existing expertise within sister companies Intervet and Organon. Nobilon focuses on respiratory and traveler's diseases. One of its core expertises is large scale cell culture production of viruses, including influenza. Nobilon currently employs approximately 75 staff in production and R&D: www.nobilon.com.