Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of HGH Fragment 176-191 and Tirzepatide — mechanism, side effects, legal status, and pricing.
HGH Fragment 176-191 is a synthetic 16-residue disulfide-cyclized peptide corresponding to the C-terminal region (residues 176–191) of human growth hormone. It is classified as a lipolytic/GH-fragment peptide, not a full growth hormone. The compound is prohibited at all times under WADA Section S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics). Not FDA-approved for any indication; clinical development of the related analogue AOD9604 was discontinued in 2007 after a pivotal Phase IIb obesity trial failed its primary efficacy endpoint.
Tirzepatide is a unimolecular dual GIP and GLP-1 receptor agonist FDA-approved as Mounjaro for type 2 diabetes (2022), Zepbound for chronic weight management in adults with obesity or overweight with a weight-related comorbidity (2023), and Zepbound for moderate-to-severe obstructive sleep apnea in adults with obesity (2024). It has a half-life of approximately 5 days, allowing once-weekly subcutaneous dosing.
HGH Fragment 176-191
Tirzepatide
Category
Legal Status
Mechanism
Half-life
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
HGH Fragment 176-191
No pricing data yet.
Check HGH Fragment 176-191 prices →Tirzepatide
COA corpus from Disclosed Labs — independently tested batches only.
HGH Fragment 176-191
1
COAs
99.2%
Avg purity
1
Labs
Tirzepatide
306
COAs
99.7%
Avg purity
15
Labs
No human data were found for the native peptide (CAS 66004-57-7, Phe176) itself. All identified human clinical work was conducted on AOD9604, a distinct N-terminal Tyr-substituted analogue: six sponsor-run, randomized, double-blind, placebo-controlled trials (Phase I–IIb, 2001–2006, ~900 total subjects, including a ~502-subject 24-week Phase IIb obesity trial) assessed safety and later weight-loss efficacy. Reported: good tolerability, no serious adverse events, no IGF-1 elevation—but the pivotal Phase IIb trial did not meet its primary weight-loss endpoint versus placebo and Metabolic Pharmaceuticals discontinued development in 2007. In obese Zucker rats, oral AOD9604 (500 µg/kg/day × 19 days) reduced body-weight gain by >50% and increased adipose lipolytic activity without impairing insulin sensitivity. In obese and lean mice, both hGH and AOD9604 reduced weight gain and increased fat oxidation and plasma glycerol; unlike hGH, AOD9604 caused no hyperglycemia and did not compete for the hGH receptor. In β3-AR knockout mice, chronic lipolytic/weight effects were lost while acute energy-expenditure increases persisted. Intra-articular AOD9604 combined with hyaluronic acid outperformed either agent alone in a rabbit collagenase-induced knee osteoarthritis model.
Key references
The SURPASS program established efficacy in type 2 diabetes, including SURPASS-2 (Frias et al., NEJM 2021), in which tirzepatide was superior to semaglutide 1 mg for A1C reduction and body weight. The SURMOUNT-1 obesity trial (Jastreboff et al., NEJM 2022) demonstrated up to approximately 20.9% mean body-weight reduction at 15 mg over 72 weeks. SURMOUNT-OSA (Malhotra et al., NEJM 2024) showed large reductions in apnea-hypopnea index in obstructive sleep apnea with obesity, supporting the 2024 FDA indication (Zepbound for moderate-to-severe OSA in adults with obesity). The SUMMIT trial (Packer et al., NEJM 2025) demonstrated a lower risk of cardiovascular death or worsening heart failure in HFpEF with obesity.
HGH Fragment 176-191 and Tirzepatide are both in the Metabolic category and may have overlapping mechanisms. Researchers should review both profiles carefully, understand the mechanisms of action, and monitor the relevant biomarkers when combining compounds in the same class. As always, consult a licensed healthcare provider before making any decisions about combining research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Contraindications
Lab Testing
Disclosed Labs