Side-by-side · Research reference

CJC-1295 (no DAC)vsThymosin α-1

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

APhase 1Reviewed15/51 cited

BPhase 3Reviewed8/39 cited

CJC-1295 (no DAC)

Short-acting GHRH · No DAC variant

100 mcgPer doseTeichman 2006

~30 minHalf-lifeIonescu 2006

Phase 1Evidence levelTeichman 2006 Sigalos 2018

SQ · Pre-sleep · 1–2×/day

Thymosin α-1

Immune modulator · Approved (some countries)

1.6 mgPer doseIyer 2007

Phase 3Evidence levelIyer 2007 Camerini 2001

~2 hrHalf-life

SQ · 2× weekly · 6+ months for chronic indications

01Mechanism of Action

Parameter

CJC-1295 (no DAC)

Thymosin α-1

Primary target

Pituitary GHRH receptorTeichman 2006

Toll-like receptor 9 (TLR9) + T-cell maturation pathwayCamerini 2001

Pathway

GHRH-R → Gαs → cAMP → PKA → GH vesicle exocytosisTeichman 2006

TLR9 activation → ↑ IFN-α + IL-2 + IFN-γ → enhanced T-cell function + dendritic cell maturationIyer 2007

Downstream effect

Pulsatile GH release matching physiological pattern; subsequent IGF-1 elevationIonescu 2006

Restored T-cell function, improved viral clearance, anti-tumour adjuvant effectsIyer 2007

Feedback intact?

Yes — short pulse preserves somatostatin negative feedbackIonescu 2006

—

Origin

Modified human GRF 1-29 with four substitutions (D-Ala²/Gln⁸/Ala¹⁵/Leu²⁷) for protease resistanceTeichman 2006

Synthetic 28-AA peptide identical to natural Tα-1 isolated from thymus extractCamerini 2001

Antibody development

Not reported in short-term studies

—

02Dosage Protocols

Parameter

CJC-1295 (no DAC)

Thymosin α-1

Standard dose

100 mcg per injectionTeichman 2006

Often paired with ipamorelin in same syringe.

—

Frequency

1–2× daily (pre-sleep ± morning)

2× weekly (Mon/Thu typical)

Lower / starter dose

50 mcg per dose

0.8 mg per injection

Evidence basis

Phase 1 (CJC-1295 with DAC); analog dataTeichman 2006 Ionescu 2006

No-DAC variant is less studied directly; PK extrapolated from native GHRH.

Phase 3 + approved (35+ countries as Zadaxin)Iyer 2007

Duration

8–12 weeks on / 4 off (anecdotal)

6–12 months for chronic indications

Reconstitution

Bacteriostatic water

Sterile water for injection per vial label

Timing

Pre-sleep + fasted preferred

No specific time

Half-life

~30 minIonescu 2006

Short pulse vs CJC-1295-DAC (~8 days). Choose no-DAC for pulsatile, DAC for sustained.

~2 hours plasma; tissue effect days

Standard dose (HBV/HCV)

—

1.6 mg SQ 2× weekly × 6–12 monthsIyer 2007

04Side Effects & Safety

Parameter

CJC-1295 (no DAC)

Thymosin α-1

Injection site reaction

Erythema, mild pruritus

Erythema, mild discomfort

Flushing / headache

Common transient effect

—

Cortisol elevation

Minimal at standard doses

—

Prolactin elevation

Minimal

—

Glucose intolerance

Possible at high cumulative doses

—

IGF-1 elevation

Dose-dependent; monitor with chronic use

—

Cancer risk

Contraindicated in active malignancy (GH/IGF-1 axis)

No signal — used as adjuvant in oncology

Pregnancy / OB

Avoid

GI symptoms

—

Rare nausea

Fatigue

—

Common during initial weeks

Fever / flu-like

—

Mild interferon-like response possible

Autoimmune

—

Theoretical risk; caution in active autoimmune disease

Absolute Contraindications

CJC-1295 (no DAC)

·Active malignancy or cancer history
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

Thymosin α-1

·Pregnancy / breastfeeding
·Hypersensitivity to peptide
·Concurrent immunosuppressant therapy (transplant patients)

Relative Contraindications

CJC-1295 (no DAC)

·Untreated diabetes
·Severe insulin resistance

Thymosin α-1

·Active autoimmune disease
·Severe immunocompromised state without supervision

05Administration Protocol

Parameter

CJC-1295 (no DAC)

Thymosin α-1

1. Reconstitution

Add 2 mL bacteriostatic water to 2 mg vial → 1 mg/mL = 100 mcg per 0.1 mL. Roll gently.

Add 1 mL sterile water per 1.6 mg vial → 1.6 mg/mL.

2. Injection site

Subcutaneous, abdomen or thigh. Rotate sites.

SQ — abdomen, thigh, or upper arm. Rotate sites.

3. Timing

Pre-sleep preferred. Often combined with ipamorelin in the same syringe.

2× weekly, e.g. Monday + Thursday.

4. Storage

Lyophilised: room temp, protected from light. Reconstituted: refrigerate 2–8 °C, use within 30 days.

Lyophilised: refrigerate. Reconstituted: refrigerate, use within 24 h.

5. Needle

29–31G, 4–8 mm insulin syringe.

27–31G, 4–8 mm insulin syringe.

06Stack Synergy

CJC-1295 (no DAC)

+ Ipamorelin

Strong

View Ipamorelin →

CJC-1295 (no DAC) and ipamorelin are the canonical "GHRH + GHRP" dual-axis stack at physiological timing. Both peak within 30 min and clear within 2 hours, producing a sharp, high-amplitude GH pulse closely resembling natural physiology. Preferred over the CJC-1295-DAC + ipamorelin stack when pulsatility (vs sustained elevation) is the goal.

CJC-1295 (no DAC): 100 mcg SQ · pre-sleep
Ipamorelin: 200–300 mcg SQ · same injection
Primary benefit: Pulsatile GH stimulation, recovery, body composition

Teichman 2006 Raun 1998

Thymosin α-1

— no documented stacks