Protherics PLC / Angiotensin vaccine
25 April 2002 .... Protherics also announces further trials to develop its angiotensin vaccine, following successful early phase II trials.
The next trial, designed to optimise the formulation and dosing schedule for maximum antibody titres, is planned for the third quarter of 2002. The trial will use a recently enhanced formulation incorporating three times more angiotensin immunogen in the active molecule of the vaccine than used in previous trials. This trial is intended to be followed by a larger proof of concept study involving approximately 360 patients. Protherics is seeking partnership with a major pharmaceutical company to fully develop the vaccine.
On 25 March, Protherics announced successful phase II results indicating that its angiotensin vaccine is effective in inducing antibodies against angiotensin - the main objective of the trial. Statistically significant effects on aldosterone and renin levels were also observed, indicating that the vaccine interacts with the hormonal regulation of blood pressure. In addition, there was a small, dose dependent reduction in systolic blood pressure in vaccinated patients, but a much larger trial would be required to confirm statistically significant effects on blood pressure...
25 March 2002
Protherics PLC announces that it has achieved successful results from early phase II trials indicating that its angiotensin vaccine is effective at inducing antibodies against angiotensin, an important hormone target for the treatment of hypertension (high blood pressure). Inhibition of angiotensin is known to reduce blood pressure.
The results show that angiotensin antibodies were induced in all 17 patients treated with the vaccine over a six-week period, with antibody levels peaking three weeks after the last dose. In addition, the results identified a long antibody half-life of more than two months, which supports Protherics' aim of developing a long-term treatment for hypertension by a primary immunisation followed by booster injections once or twice a year. Other significant pharmacological reactions were observed indicating that the vaccine interacts with the hormonal regulation of blood pressure.
Commenting on the results, Andrew Heath, Chief Executive said:
'We are very encouraged by these latest results in patients which support
earlier positive test data. The next step will be to optimise the formulation to maximise antibody titres and then progress to large scale patient studies to enable us to determine the effect of the vaccine on blood pressure.'
Professor M J Brown, Clinical Pharmacology Unit, Addenbrookes' Hospital,
Cambridge said:
'The angiotensin system is a prime target for a number of drugs to treat high blood pressure or heart disease. Development of a treatment that avoids the need for daily drug therapy is an appealing prospect. This study is an important step in that direction, demonstrating that long-lived immunity can be generated in patients with high blood pressure. The vaccine was generally well tolerated by patients.' |
