Angiotensin II – Peptide for Blood Pressure Support and Other Related Cardiovascular Complications

Angiotensin II may help patients with severe low blood pressure, especially those in septic shock. It works by tightening blood vessels and helping the body retain fluid, which can raise blood pressure and improve blood flow to vital organs like the kidneys and brain.

Angiotensin II is a peptide, specifically an octapeptide (a peptide consisting of eight amino acids). It acts as a primary active peptide hormone in the renin-angiotensin-aldosterone system (RAAS), functioning as a potent vasoconstrictor to regulate blood pressure and fluid balance

FDA-Approved Uses of Angiotensin II

Angiotensin II is FDA-approved to increase blood pressure in adults experiencing septic or other distributive (vasodilatory) shock. It is a life-threatening condition. In such conditions blood pressure falls dangerously low despite fluid resuscitation and conventional vasopressor therapy (e.g., norepinephrine).

Specific Clinical Uses of Angiotensin II

Used when patients require vasopressor support ≥0.2 mcg/kg/min norepinephrine equivalents
After adequate fluid resuscitation (≥25 mL/kg within 3 hours)
Primarily septic shock, but covers all distributive/vasodilatory shock states
Administered exclusively in ICU/critical care settings with continuous hemodynamic monitoring

Other uses of Angiotensin II

Perioperative hypotension during cardiac surgery and liver transplantation
Intraoperative vasodilation during kidney transplantation (published case series)
Hepatorenal syndrome (HRS) — emerging data
COVID-19-associated distributive shock (used during pandemic).

Trade Names Angiotensin II of in USA and Manufacturers

FDA-Approved Brand:

Giapreza® (angiotensin II injection, 2.5 mg/mL concentrate for IV infusion)
Manufacturer: La Jolla Pharmaceutical Company (San Diego, CA)
NDC: Available in 1 mL single-dose vials (2.5 mg per vial)
No FDA-approved generic equivalent as of May 2026 (patent-protected)

Molecular identity (Giapreza):

Synthetic octapeptide (8 amino acids) with structure IDENTICAL to endogenous human angiotensin II
Sequence: Asp-Arg-Val-Tyr-Ile-His-Pro-Phe
MW: ~1,046 Daltons
Produced by total chemical synthesis (not derived from plasma)
Formulation: Sterile, concentrated solution; diluted before IV infusion

Dosage of Angiotensin II

FDA-Approved Dosing of Angiotensin II,

Initiation:

Starting dose: 20 ng/kg/min IV continuous infusion
Dilution: Dilute in 0.9% NaCl to a concentration of 5,000 ng/mL or 10,000 ng/mL
Commercial pre-diluted bags also available from some centers

Titration (to achieve target MAP):

Target MAP: ≥65 mmHg
Increase by: Up to 15 ng/kg/min every 5 minutes
Maximum maintenance dose: 80 ng/kg/min
If needed within first 3 hours: may increase up to 200 ng/kg/min during acute rescue

Maintenance:

Maintain at lowest effective dose to achieve target MAP
Wean gradually as hemodynamics stabilize
Do NOT abruptly discontinue

Administration requirements:

Continuous IV infusion only (NEVER IV bolus)
Dedicated IV line preferred
Continuous arterial blood pressure monitoring required
Concurrent venous thromboembolism (VTE) prophylaxis REQUIRED (boxed warning)
Concurrent antifibrinolytic use NOT recommended
ICU/critical care setting ONLY

Storage: Refrigerate at 2–8°C; do not freeze; protect from light

Price of Angiotensin II

Hospital-administered drug; patients do not purchase directly. Costs included in ICU billing.

Approximate acquisition cost:

Per 1 mL vial (2.5 mg): ~$1,500 per vial
A typical ICU course lasting 24–72 hours may require multiple vials
Estimated total drug cost per patient course: ~$3,000–$10,000+ depending on duration and dose
[Costs are absorbed into hospital/ICU billing and not separately charged to patients at most institutions]

La Jolla Pharmaceutical offers a Wastage Product Replacement Program for hospitals:
Hospitals may receive replacement vials for unused portion if MAP target was not achieved within first 3 hours, under specific eligibility criteria.

Coverage by Insurance Type for Angiotensin II

Angiotensin II is covered by most common insurance plans.

ACA Marketplace / Commercial Insurance:
Covered as ICU/inpatient drug under hospital benefit
Employer Insurance:
Covered under inpatient/hospital benefit
Medicare Part A (Inpatient Hospital):
Covered as ICU inpatient drug under Part A hospital benefit
Medicare Part D:
N/A — hospital-only drug administered by healthcare providers
Medicaid:
Covered for medically necessary inpatient critical care use
TRICARE (Military):
Covered for inpatient critical care use

Tips for Availing Insurance Coverage

Giapreza is exclusively an ICU/hospital drug.
ACE inhibitors (e.g., lisinopril, enalapril) INCREASE the response to Giapreza. If a patient is on an ACE inhibitor, expect an enhanced and potentially prolonged vasopressor effect — adjust dosing accordingly.
ARBs (e.g., losartan, valsartan) REDUCE the response to Giapreza by blocking AT1 receptors. For larger doses may be required in patients on chronic ARB therapy.
VTE prophylaxis is MANDATORY when using Giapreza. The ATHOS-3 trial showed 13% thromboembolic event rate vs. 5% placebo. Use concurrent anticoagulation per ICU protocol.
Giapreza is NOT a first-line vasopressor. It is a rescue agent for refractory distributive shock that has failed norepinephrine and/or vasopressin.

Side Effects of Angiotensin II

From FDA prescribing information and ATHOS-3 clinical trial data (n=321):

Common adverse reactions (>10%):
Thromboembolic and thrombotic events: 13% (vs. 5% placebo) — most common clinically significant event

Other adverse reactions observed:

Hypertension (blood pressure overshoot): Risk with rapid titration or excessive dosing

Peripheral ischemia: Risk of end-organ ischemia with excessive vasoconstriction
Tachycardia / bradycardia: Reflex changes in heart rate
Acidosis: Metabolic consequences in critically ill patients
Delirium / altered mental status: Confounded by critical illness context
Fungal infection: Observed in ATHOS-3; possibly disease-related in immunocompromised shock patients
Thrombocytopenia (low platelet count)

Drug interactions:

ACE inhibitors: INCREASE response to Giapreza (increased vasoconstriction)
ARBs (angiotensin receptor blockers): DECREASE response to Giapreza (AT1 receptor blockade)
Antifibrinolytic agents: Concurrent use NOT recommended (additive thrombotic risk)

Patient population note: Most adverse events in ATHOS-3 were confounded by critical illness baseline — attributing individual events to Giapreza vs. underlying septic shock is clinically challenging.

Contraindications

Per FDA Giapreza prescribing information:

Contraindicated:
– Known hypersensitivity to angiotensin II or any component of Giapreza formulation

Warnings and precautions (not absolute contraindications but require careful management):

Thromboembolic risk: Concurrent VTE prophylaxis required for all patients
Concurrent antifibrinolytic agents: NOT recommended due to additive clot-promoting risk
Pregnancy: Not recommended — angiotensin II causes fetal harm (known teratogen in RAAS pathway; similar drugs cause fetal renal toxicity, oligohydramnios, fetal death)
Breastfeeding: Unknown if excreted in human milk; benefit-risk assessment required in critical care context

Clinical context considerations:

Not intended for use outside ICU/critical care with continuous hemodynamic monitoring
Not for non-distributive shock (cardiogenic, obstructive, hypovolemic)
Patients on chronic ACE inhibitors: Enhanced and prolonged response expected

Pharmacology of Angiotensin II

Angiotensin II (Giapreza) is a synthetic octapeptide (8 amino acids) with a structure IDENTICAL to endogenous human angiotensin II. The primary active effector peptide of the renin-angiotensin-aldosterone system (RAAS). Sequence: Asp-Arg-Val-Tyr-Ile-His-Pro-Phe. MW ~1,046 Daltons. Synthesized by total chemical synthesis (not plasma-derived). Formulated as a sterile concentrate (2.5 mg/mL in 0.9% NaCl for dilution before infusion).

Endogenous angiotensin II is produced by the sequential cleavage of angiotensinogen → angiotensin I (renin enzyme) → angiotensin II (ACE enzyme). It is the master vasoconstrictor of the body and the primary regulator of blood pressure, fluid balance, and aldosterone secretion.

Pharmacokinetics (Giapreza):

Onset: Rapid (within minutes of IV infusion initiation)
Distribution half-life: <1 minute
Elimination half-life: ~1 minute
Clearance: Independent of renal and hepatic function (important in critically ill patients with multi-organ failure)
Metabolism: Aminopeptidase A cleavage → angiotensin III (retains ~10–25% vasopressor activity) and further metabolites

Mechanism of Action in Angiotensin II

Angiotensin II binds to AT1 receptors (angiotensin type 1 receptors) — G-protein coupled receptors (Gq/11). It expressed widely in vascular smooth muscle, adrenal cortex, heart, kidney, and brain:

Vasoconstriction

Activation of the angiotensin II type 1 receptor (AT1R) starts a chain reaction inside blood vessels. This reaction increases calcium (Ca²⁺) levels in smooth muscle cells, causing the blood vessels to tighten, a process called vasoconstriction. When the vessels become narrower, systemic vascular resistance (SVR) and mean arterial pressure (MAP) increase. This effect is important in shock management because it helps raise blood pressure and improve blood flow to vital organs.

Aldosterone Release

When AT1R is activated in the adrenal cortex, it causes the release of a hormone called aldosterone. Aldosterone helps the kidneys keep more sodium (Na⁺) and water in the body. This increases the amount of circulating blood, which provides extra support for raising blood pressure.

Renal Effects

Activation of AT1R causes constriction of the efferent arterioles in the kidneys, which increases pressure inside the glomeruli and helps support filtration. Early research suggests this effect may help improve vasodilatory acute kidney injury (AKI) linked to septic shock.

Interaction with vasopressin deficiency

Distributive shock is characterized by relative vasopressin deficiency AND RAAS dysregulation. Angiotensin II directly addresses the RAAS component, complementing catecholamines and vasopressin.

Result Claims By Different Companies

La Jolla Pharmaceutical Company (based on ATHOS-3 pivotal trial data supporting FDA approval):

ATHOS-3 Trial (Phase 3, n=321, multicenter, randomized, double-blind, placebo-controlled):

Primary endpoint: Cardiovascular SOFA score response at 3 hours (MAP ≥75 mmHg or ≥10 mmHg increase from baseline without increasing background vasopressors)
69.9% responders in Giapreza arm vs. 23.4% in placebo arm (p<0.001)
Statistically significant primary endpoint met

Secondary endpoint: 28-day all-cause mortality

46% mortality in Giapreza arm vs. 54% in placebo arm
Hazard ratio 0.78 (95% CI 0.57–1.07) — trend toward benefit, NOT statistically significant
FDA approved despite non-significant mortality benefit based on the blood pressure endpoint

Additional ATHOS-3 findings:

Patients with low baseline renin levels (indicating intact RAAS capacity) showed greater vasopressor response and better survival benefit
Mean norepinephrine dose reduced in Giapreza arm — suggests catecholamine-sparing effect

Manufacturer claim: ‘Giapreza (angiotensin II) increases blood pressure in adults with septic or other distributive shock.’

Independent assessment:

PMC commentary (2018): ATHOS-3 raised questions about safety (thromboembolic events) and whether blood pressure normalization is a valid surrogate for meaningful clinical outcomes. 28-day mortality benefit was not statistically proven.
Giapreza represents a mechanistically novel vasopressor addressing RAAS deficiency in shock — clinical positioning as third-line/rescue vasopressor is appropriate given the evidence profile.

Disclaimer

This content about “Angiotensin II is is for informational and educational purposes only, is not medical advice, does not replace consultation with a licensed healthcare professional, and affiliate links may result in compensation at no additional cost to you.

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