CYT006-AngQb
Encyclopedia
CYT006-AngQb was an investigational vaccine
against angiotensin II, designed to lower blood pressure
. It was somewhat effective in clinical trial
s, but less so than conventional drugs against hypertension
(elevated blood pressure).
causes the immune system to produce antibodies which reduce angiotensin II blood levels, lowering blood pressure.
Side effects were mild and included local reactions, headache and fatigue.
The 2008 trial was small and exploratory. It did not address the question of whether the vaccine actually protects internal organs, nor did it address safety concerns such as whether the vaccine would cause autoimmune disease. If a standard drug treatment is found to dangerously inhibit the renin-angiotensin-aldosterone system, it can be withdrawn and the effects reversed quickly, but that would not be true of the vaccine. However, poor compliance to standard treatment is the main reason for inadequate control of blood pressure, and if vaccination were safe and effective in the long run, it may solve many compliance problems.
CYT006-AngQb did not reach Phase III studies because the antihypertensive effects were small compared to existing ACE inhibitor
s and angiotensin II receptor antagonist
s, and they were not reproducible across dosing schemes. Similar vaccines with modified immunogens and different adjuvant
s are being investigated.
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...
against angiotensin II, designed to lower blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
. It was somewhat effective in clinical trial
Clinical trial
Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...
s, but less so than conventional drugs against hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
(elevated blood pressure).
Method of action
Angiotensin II causes blood vessels to constrict, and drives blood pressure up. CYT006-AngQb consists of virus-like particles covalently coupled to angiotensin II. Subcutaneous injectionSubcutaneous injection
A subcutaneous injection is administered as a bolus into the subcutis, the layer of skin directly below the dermis and epidermis, collectively referred to as the...
causes the immune system to produce antibodies which reduce angiotensin II blood levels, lowering blood pressure.
Studies
In a 2008 phase IIa study, 72 patients received 100 µg, 300 µg or placebo in weeks 0, 4, and 12. Blood pressure was lowered dose-dependently, by 5.6 mmHg (systolic) and 2.8 mmHg (diastolic) in the 300 µg group. Morning blood pressure (8:00) was lowered by 25 mmHg (systolic) and 13 mmHg (diastolic).Side effects were mild and included local reactions, headache and fatigue.
The 2008 trial was small and exploratory. It did not address the question of whether the vaccine actually protects internal organs, nor did it address safety concerns such as whether the vaccine would cause autoimmune disease. If a standard drug treatment is found to dangerously inhibit the renin-angiotensin-aldosterone system, it can be withdrawn and the effects reversed quickly, but that would not be true of the vaccine. However, poor compliance to standard treatment is the main reason for inadequate control of blood pressure, and if vaccination were safe and effective in the long run, it may solve many compliance problems.
CYT006-AngQb did not reach Phase III studies because the antihypertensive effects were small compared to existing ACE inhibitor
ACE inhibitor
ACE inhibitors or angiotensin-converting enzyme inhibitors are a group of drugs used primarily for the treatment of hypertension and congestive heart failure...
s and angiotensin II receptor antagonist
Angiotensin II receptor antagonist
Angiotensin II receptor antagonists, also known as angiotensin receptor blockers , AT1-receptor antagonists or sartans, are a group of pharmaceuticals which modulate the renin-angiotensin-aldosterone system...
s, and they were not reproducible across dosing schemes. Similar vaccines with modified immunogens and different adjuvant
Immunologic adjuvant
In immunology, an adjuvant is an agent that may stimulate the immune system and increase the response to a vaccine, without having any specific antigenic effect in itself. The word “adjuvant” comes from the Latin word adiuvare, meaning to help or aid...
s are being investigated.