Side-by-side · Research reference

ARA 290vsHGH 191AA

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 2HUMAN-REVIEWED17/59 cited

BFDA-ApprovedHUMAN-REVIEWED0/75 cited

ARA 290

EPO-Derived Peptide · Innate Repair Receptor Agonist

4 mgDaily doseBrines 2015 Culver 2017

28 daysPhase 2 durationCulver 2017

Non-erythropoieticSafety profileBrines 2015 Liu 2014

SQ · DailyBrines 2015 Culver 2017

HGH 191AA

Recombinant hGH · FDA-Approved

0.024–0.034 mg/kg/dayPediatric GHD dose

2–4 hoursPlasma half-life

191 AASequence length

SQ · Daily · Evening preferred

01Mechanism of Action

Parameter

ARA 290

HGH 191AA

Primary target

Innate repair receptor (EPO receptor / CD131 heterodimer)

Growth hormone receptor (GHR) — JAK2/STAT5 pathway

Pathway

EPO/CD131 → JAK2 activation → PI3K/AKT, MAPK signaling → anti-inflammatory, anti-apoptotic cascades

GHR activation → JAK2/STAT5 → liver IGF-1 synthesis + direct metabolic effects

Downstream effect

Tissue protection, nerve fiber regeneration, suppression of inflammatory macrophage activation, altered T-cell differentiation (↑Treg, ↑Th2, ↓Th1)Liu 2014 Culver 2017

Linear growth, lipolysis, protein synthesis, nitrogen retention, carbohydrate metabolism modulation

Feedback intact?

N/A — does not interact with hematopoietic EPO receptorLiu 2014

No — exogenous GH bypasses hypothalamic-pituitary axis, suppresses endogenous pulsatility

Origin

11-amino-acid sequence from EPO helix B, engineered to eliminate hematopoietic activity while retaining tissue-protective properties

Recombinant DNA technology — 191 AA, identical to pituitary hGH, no methionyl residue

Antibody development

Not reported in clinical trials

Rare — <2% develop binding antibodies, typically non-neutralizing

02Dosage Protocols

Parameter

ARA 290

HGH 191AA

Standard dose (Phase 2)

4 mg / dayBrines 2015 Culver 2017

Sarcoidosis SFN and diabetic neuropathy trials.

—

Frequency

Once daily

Self-administered subcutaneously.

Once daily, typically evening

Evening administration mimics physiological GH pulse.

Duration

28 days (Phase 2)Culver 2017

Corneal nerve improvements observed by day 28.

Years (children until epiphyseal closure); indefinite (adult GHD)

Evidence basis

Phase 2 RCTsCulver 2017 Brines 2015

64-subject sarcoidosis trial, type 2 diabetes trial.

FDA-approved / decades of RCT data

Route

SubcutaneousBrines 2015

—

Timing

Any time of day

No circadian dependence reported.

—

Pediatric GHD

—

0.024–0.034 mg/kg/day SQ

6–7× per week dosing typical. Brand-specific ranges.

Adult GHD

—

0.004–0.016 mg/kg/day SQ

Start low, titrate based on IGF-1 levels.

Turner syndrome

—

0.045–0.050 mg/kg/day SQ

Idiopathic short stature

—

0.037 mg/kg/day SQ

AIDS wasting

—

0.1 mg/kg/day SQ (high-dose)

Short-term indication. Monitor glucose.

Monitoring

—

IGF-1, glucose, thyroid function, bone age (children)

03Metabolic / Fat Loss Evidence

Parameter

ARA 290

HGH 191AA

Primary effect

Improved metabolic control (HbA1c, fasting glucose)Brines 2015

Secondary to neuropathy treatment; direct lipolytic effects not established.

—

HbA1c

Significant reduction vs placebo

Observed in type 2 diabetes + neuropathy trial.

—

Fasting glucose

Improved in ARA 290 group

—

Body composition

Not directly quantified

Fat loss not a primary endpoint; metabolic improvements may reflect insulin sensitivity.

↓ fat mass, ↑ lean mass, ↑ bone mineral density (children)

Primary fat target

—

Visceral and subcutaneous adipose tissue

Mechanism

—

Lipolysis via hormone-sensitive lipase activation, FFA oxidation

Effect on lean mass

—

Significant lean mass increase (protein synthesis, nitrogen retention)

Insulin sensitivity

—

Acute insulin resistance (anti-insulin effect); chronic neutral-to-improved via fat loss

IGF-1 elevation

—

Dose-dependent, significant — primary anabolic mediator

Glucose metabolism

—

Hyperglycemia risk, especially high doses (AIDS wasting)

Clinical context

—

FDA-approved for AIDS wasting (cachexia). Off-label use for body recomposition lacks long-term safety data.

04Side Effects & Safety

Parameter

ARA 290

HGH 191AA

Injection site reaction

Mild, transient

Lipohypertrophy, lipoatrophy, erythema (rotate sites)

Hematopoiesis

None — non-erythropoietic

Distinguishes ARA 290 from native EPO.

—

Cardiovascular

No thrombotic events or hypertension reported

—

Immunogenicity

No antibody formation reported

—

Tolerability

Well-tolerated in Phase 2 trialsCulver 2017 Brines 2015

—

Fluid retention / Edema

—

Peripheral edema, arthralgia, carpal tunnel syndrome (dose-dependent)

Glucose intolerance

—

Hyperglycemia, new-onset diabetes (anti-insulin effect)

Intracranial hypertension

—

Benign intracranial hypertension (pseudotumor cerebri) — headache, visual changes, papilledema

Slipped capital femoral epiphysis

—

SCFE risk in children — limp, hip/knee pain (requires surgery)

Scoliosis progression

—

Rapid growth may unmask/progress scoliosis (monitor spine in children)

Hypothyroidism

—

Central hypothyroidism unmasking or worsening (monitor TSH, free T4)

Cancer risk

—

Contraindicated in active malignancy. Theoretical risk in cancer survivors (controversial).

Antibody formation

—

Rare (<2%), typically non-neutralizing. Loss of efficacy if neutralizing antibodies develop.

Pancreatitis

—

Rare. Higher risk in children with certain syndromes (Prader-Willi).

Gynecomastia

—

Adolescent males (physiological during puberty, may be exacerbated)

Absolute Contraindications

ARA 290

·Hypersensitivity to ARA 290

HGH 191AA

·Active malignancy or history of cancer (especially childhood cancer survivors with risk factors)
·Acute critical illness (post-cardiac surgery, trauma, acute respiratory failure)
·Diabetic retinopathy (active proliferative or severe non-proliferative)
·Prader-Willi syndrome with severe obesity, sleep apnea, or respiratory impairment
·Closed epiphyses (for growth indications)

Relative Contraindications

ARA 290

·Active malignancy (theoretical EPO-axis concern; not observed in trials)

HGH 191AA

·Diabetes mellitus (monitor closely, may require insulin adjustment)
·Intracranial lesions or history of intracranial hypertension
·Scoliosis (monitor curve progression)
·Untreated hypothyroidism (treat before GH initiation)
·Severe obesity (assess OSA risk, cardiovascular status)

05Administration Protocol

Parameter

ARA 290

HGH 191AA

1. Preparation

Reconstitute lyophilised powder per manufacturer instructions. Use sterile technique.

Add diluent (sterile water or bacteriostatic water per manufacturer) to vial. Swirl gently — do not shake. Solution should be clear, colorless. Concentration varies by brand (e.g., 5 mg or 10 mg per vial).

2. Injection site

Subcutaneous — abdomen, thigh, or upper arm. Rotate sites to avoid lipohypertrophy.

Subcutaneous — rotate sites: abdomen, thigh, buttocks, upper arm. Avoid same site within 1 cm for 2 weeks to prevent lipodystrophy.

3. Timing

Once daily, any time of day. Self-administered in Phase 2 trials.Brines 2015

Once daily, evening preferred (6–8 PM or pre-sleep). Mimics physiological nocturnal GH secretion. Consistency is critical.

4. Dosing

4 mg daily for 28 days (Phase 2 protocol). Duration for chronic use not established.Culver 2017

Unreconstituted: refrigerate 2–8 °C, protect from light. Reconstituted: refrigerate, use within 14–28 days (brand-specific). Do not freeze.

5. Storage

Lyophilised: store at controlled room temperature. Reconstituted: refrigerate, use within specified timeframe.

27–31G, 4–8 mm insulin syringe or pen device. Pinch skin, 45–90° angle depending on subcutaneous thickness.

6. Monitoring

—

Baseline and periodic: IGF-1 (target age/sex-adjusted midrange), fasting glucose, HbA1c, thyroid function (TSH, free T4), bone age (children), lipid panel. Fundoscopy if headache/visual symptoms.

06Stack Synergy

ARA 290

+ BPC-157

Moderate

View BPC-157 →

ARA 290 targets the innate repair receptor (EPO/CD131) for nerve regeneration and anti-inflammatory signaling, while BPC-157 promotes angiogenesis and tissue repair through distinct mechanisms (likely involving VEGF, growth hormone receptor pathways). Combined, they may address both neuroinflammation and structural tissue repair in neuropathy or injury models. No direct clinical data; mechanistic overlap in tissue protection.

ARA 290: 4 mg SQ · daily
BPC-157: 250–500 mcg SQ · daily
Frequency: Once daily, same or separate injections
Primary benefit: Nerve regeneration, pain reduction, tissue healing

HGH 191AA

+ Ipamorelin

Moderate

View Ipamorelin →

Ipamorelin (GHRP) stimulates endogenous GH release, which is redundant when exogenous rhGH is administered. However, ipamorelin may still amplify pulsatility of remaining endogenous secretion in partial GHD or during GH dose titration. Not typically combined in standard clinical practice; more common in experimental or off-label protocols. Limited evidence for additive benefit.

HGH 191AA: Standard dose per indication
Ipamorelin: 100–200 mcg SQ · morning (if used)
Note: Monitor IGF-1 closely; avoid supraphysiological levels
Primary benefit: Theoretical enhancement of pulsatility; limited clinical rationale

+ Tesamorelin

Weak

View Tesamorelin →

Tesamorelin (GHRH analogue) stimulates endogenous GH secretion, which is unnecessary when exogenous rhGH is already provided. Combining both offers no mechanistic advantage and increases cost, side effects, and IGF-1 elevation risk. Not recommended in clinical practice.

Note: Combination not recommended — choose one GH modality
Primary benefit: None — redundant mechanisms