CYT006-AngQb was an investigational

vaccine A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease. The safety and effectiveness of vaccines has been widely studied and verified.

against angiotensin II, designed to lower blood pressure. It was somewhat effective in

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...

s, but less so than conventional drugs against hypertension (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

covalent A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms ...

ly coupled to angiotensin II. Subcutaneous injection 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 (5:00-8:00) 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 If a standard drug treatment is found to dangerously inhibit the renin-angiotensin-aldosterone system, it can be withdrawn and the effects reversed quickly, but that would not be true of the vaccine.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 inhibitors and

angiotensin II receptor antagonist Angiotensin II receptor blockers (ARBs), formally angiotensin II receptor type 1 (AT1) antagonists, also known as angiotensin receptor blockers, angiotensin II receptor antagonists, or AT1 receptor antagonists, are a group of pharmaceuticals tha ...

s, and they were not reproducible across dosing schemes. Similar vaccines with modified

immunogen An immunogen is any substance that generates B-cell (humoral/antibody) and/or T-cell (cellular) adaptive immune responses upon exposure to a host organism. Immunogens that generate antibodies are called antigens ("antibody-generating"). Immunogen ...

s and different

adjuvant In pharmacology, an adjuvant is a drug or other substance, or a combination of substances, that is used to increase the efficacy or potency of certain drugs. Specifically, the term can refer to: * Adjuvant therapy in cancer management * Analgesi ...

s are being investigated.

References

{{DEFAULTSORT:Cyt006angqb Vaccines Antihypertensive agents