Biopharmaceutical firm Protherics has acquired a new adjuvant from Dutch company CoVaccine that it will use for its hypertension vaccine, hoping to boost antibody production by tenfold.
The adjuvant is a sucrose fatty acid sulphate ester that promises to increase both humoral and cell-mediated immune responses to experimental vaccines following intramuscular administration, so Protherics found it to be a good target for its Angiotensin vaccine after considering a number of third party proprietary adjuvants.
The global market for the treatment of high blood pressure is estimated to be in excess of €24bn annually, making the Angiotensin vaccine, if successful, a major out-licensing opportunity for Protherics, as current treatments are tablet based, require daily doses, sometimes for life, and patient compliance is often poor.
However, in preclinical models, compared to the conventional use of aluminium hydroxide as adjuvant, the new formulation containing CoVaccine's adjuvant resulted in a rise, by a factor of ten, in antibody production against angiotensin, a peptide hormone that plays a key role in the regulation of blood pressure.
The London-based company has already completed non-clinical safety testing of the CoVaccine adjuvant and is starting good manufacturing practice (GMP) production of both the adjuvant and the vaccine to use in a phase IIa proof of concept study in the second half of 2007.
The goal of this study will be to confirm that the new formulation increases levels of anti-angiotensin antibodies in hypertensive patients and to establish whether this results in a reduction in blood pressure.
"The adjuvant has been used in animal models and toxicology studies with other vaccines but has not yet been administered to man," Sally Waterman, director of Research & Development at Protherics, told In-PharmaTechnologist.com.
"The adjuvant and vaccine conjugate will be manufactured separately and then mixed prior to filling into vials so there is no particular issue with scale up."
Protherics will pay CoVaccine more than €1m in the form of 295,413 shares, following the signing of the deal, and a further 590,826 shares upon completion of two development related milestones.
CoVaccine, which has now ceased all operational activities, is also entitled to receive a "low single-digit royalty" on net sales of products containing the CoVaccine adjuvant.
Protherics' strategy is to use the revenues generated from its marketed products to help fund the advancement of its development pipeline.
The British firm's two lead programmes are CytoFab, for severe sepsis, which has been out-licensed to AstraZeneca and is being prepared for a pivotal phase III trial, and Voraxaze, for the control of high dose methotrexate therapy in cancer, where discussions are on-going with the US and EU regulators regarding marketing approvals.