Mental HealthBiotechnology Reports Biochemical Findings From Phase IIa Study With Hypertension Vaccine CYT006-AngQb
Cytos Biotechnology Ltd (SIX:CYTN) announced results from a biochemical analysis from a phase IIa study (study 02) with the vaccine
candidate CYT006-AngQb for the treatment of hypertension. CYT006-AngQb has demonstrated in a
first phase IIa study (study 01) a significant reduction of the day-time ambulatory blood pressure of
-9 / -4 mmHg (systolic/diastolic) vs. placebo (The Lancet 2008, 371:821). In study 02 an accelerated
treatment regimen with injections at weeks 0, 2, 4, 6, and 10 was tested, while in study 01 the
vaccine was given at weeks 0, 4, and 12. This modification was anticipated to induce higher
antibody titers and, thereby, a stronger blood pressure reduction. While first study results which
were communicated on March 17, 2009 showed on average a 5-fold higher antibody titer in study 02
than in study 01, the blood pressure reductions in study 02 were much lower than in study 01; they
amounted to -2.3 / -0.4 mmHg. In order to understand this discrepancy, the biochemical properties
of the induced antibody responses were analyzed in detail. The main findings are as follows:
- Antibody affinities (i.e. the strength by which the antibodies bind angiotensin II)
determined by different biochemical methods were significantly lower in study 02 than in
study 01 (pAbout the hypertension vaccine CYT006-AngQb
CYT006-AngQb is a therapeutic vaccine in development for the treatment of hypertension1,2. It is
designed to instruct the patient"s immune system to produce an antibody response against
angiotensin II. Angiotensin II is a small peptide in the body and part of the renin-angiotensin
system (RAS), which is an important regulator of blood pressure. Angiotensin II causes blood vessels
to narrow, resulting in increased blood pressure. In a phase IIa study with hypertensive patients, vaccination with CYT006-AngQb has been shown to significantly reduce the mean ambulatory daytime
blood pressure by induction of antibodies that bind angiotensin II (The Lancet 2008, 371:821).
A particularly strong blood pressure reduction has been observed in the early morning hours - a
crucial time of day when adverse cardiovascular events are more likely to occur than during other
times of the day.
CYT006-AngQb is a first-in-class product candidate in this important indication and represents a
completely novel approach to hypertension treatment. Treatment with CYT006-AngQb should allow
for convenient dosing schedules and a smooth control of blood pressure due to a sustained antibody
response induced by vaccination.
About hypertension
Hypertension, also termed high blood pressure, is a medical condition where the blood pressure is
chronically elevated. Although symptomless in nature and in itself rarely an acute problem,
persistent hypertension is one of the most important preventable causes of premature death
worldwide and contributes to around half of all cardiovascular diseases3. It is one of the major risk
factors for stroke, myocardial infarction, heart failure, and vascular disease, and is a leading cause of
chronic renal failure. Genetic predisposition and lifestyle habits such as inadequate physical activity,
high fat diet, and high salt intake promote high blood pressure. Up to 30% of adults in most
countries suffer from hypertension. Despite effective and relatively inexpensive treatment available,
less than one out of four hypertensive individuals have their blood pressure controlled successfully4,5.
This poor overall treatment success is mainly attributed to the symptomless nature of hypertension
and the necessity for long-term treatment with currently available medications that require at least
once daily self-administration.
References
1. Journal of Hypertension; A vaccine for hypertension based on virus-like particles: preclinical
efficacy and phase I safety and immunogenicity; 2007, 25:63
2. The Lancet; Effect of immunization against angiotensin II with CYT006-AngQb on ambulatory
blood pressure: a double-blind, randomized, placebo-controlled phase IIa study; 2008, 371:821
3. Centres for Disease Control and Prevention (CDC); The Atlas of Heart Disease and Stroke, 2004
4. Journal of the American Medical Association (JAMA); The Seventh Report of the Joint National
Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; 2003,
289:2560
5. National Institute for Health and Clinical Excellence (NICE), Centre for Health Services Research,
UK; Essential Hypertension: managing adult patients in primary care; August 2004
Cytos Biotechnology Ltd