Last reviewed 2026-07-08 · Next review 2026-08-07
BPC-157 and TB-500 are two of the most discussed peptides in online injury-recovery and performance communities, but they originate from fundamentally different biological sources and act through distinct mechanisms. BPC-157 is a pentadecapeptide derived from human gastric juice with reported angiogenic and anti-inflammatory properties. TB-500 is a synthetic fragment of Thymosin Beta-4, a naturally occurring peptide involved in wound healing and cell migration. Both compounds have been studied primarily in animal models and in vitro systems; published human clinical trial data is scarce for both. Neither BPC-157 nor TB-500 is FDA-approved for any indication, and both are sold as research-use-only compounds subject to FDA enforcement. This comparison documents mechanistic and evidence-level differences; it does not recommend either compound or provide treatment guidance.
Last reviewed 2026-07-08 · Next review 2026-08-08
CJC-1295 + Ipamorelin is one of the most discussed peptide stacks in online fitness and anti-aging communities, combining a growth hormone-releasing hormone (GHRH) analog with a growth hormone secretagogue (GHS) for theoretical synergistic GH release. Tesamorelin (Egrifta) is the only GHRH/GHS-class peptide with FDA approval — indicated specifically for reduction of excess visceral abdominal fat in HIV-infected patients with lipodystrophy. This comparison frames the differences in mechanism, evidence, regulatory status, and access paths without recommending either option.
Last reviewed 2026-07-08 · Next review 2026-08-07
CJC-1295 with DAC and CJC-1295 without DAC (Modified GRF 1-29) are two forms of a synthetic GHRH analog distinguished by the presence or absence of a Drug Affinity Complex moiety that binds serum albumin. The DAC variant extends the half-life from minutes to days; the non-DAC variant (Mod GRF 1-29) retains a short half-life closer to endogenous GHRH. Neither form is FDA-approved. The single published human pharmacokinetic study (Teichman et al., 2006) studied the DAC form. Both are sold as research-use-only products and are subject to FDA enforcement.
Last reviewed 2026-07-08 · Next review 2026-08-07
MK-677 (ibutamoren) and ipamorelin are both growth hormone secretagogues that stimulate GH and IGF-1 release via ghrelin receptor agonism, but they differ fundamentally in chemical class, route of administration, and evidence level. MK-677 is a non-peptide, orally active GHSR agonist developed by Merck that completed multiple Phase 2 clinical trials with published peer-reviewed data; it was never submitted for FDA approval and Merck discontinued development. Ipamorelin is a synthetic pentapeptide GHRP (growth hormone releasing peptide) requiring injection, with limited published human clinical data — primarily an original pharmacology study (Raun et al., 1998). Neither compound is FDA-approved for any indication. Both are sold as research-use-only products and are subject to FDA enforcement.
Last reviewed 2026-07-08 · Next review 2026-08-07
Retatrutide and tirzepatide are both Eli Lilly investigational peptides targeting incretin receptors for obesity and metabolic disease, but they differ in receptor pharmacology and regulatory status. Tirzepatide is a dual GIP/GLP-1 receptor agonist FDA-approved as Mounjaro (Type 2 diabetes) and Zepbound (chronic weight management). Retatrutide is a triple GLP-1/GIP/glucagon receptor agonist still in Phase 3 clinical trials (TRIUMPH program) and not approved for any indication. Early Phase 2 data showed retatrutide achieving approximately 24% weight loss at 48 weeks, while the SURMOUNT-1 Phase 3 trial showed tirzepatide achieving 22.5% mean weight loss at 72 weeks. The addition of glucagon receptor agonism in retatrutide may provide additional metabolic effects beyond weight loss, though Phase 3 confirmation is pending.
Last reviewed 2026-07-08 · Next review 2026-08-07
Semaglutide (Wegovy, Novo Nordisk) and tirzepatide (Zepbound, Eli Lilly) are both FDA-approved for chronic weight management. Semaglutide is a GLP-1 receptor agonist whose STEP 1 trial demonstrated 14.9% mean weight loss at 68 weeks. Tirzepatide is a dual GIP/GLP-1 receptor agonist whose SURMOUNT-1 trial demonstrated 22.5% mean weight loss at 72 weeks. The SURMOUNT-5 head-to-head trial directly compared both drugs for obesity and reported greater weight loss with tirzepatide (approximately 20.9%) than semaglutide (approximately 17.3%) at 72 weeks. Both are available via telehealth platforms for their FDA-approved weight management indications. Cost, insurance coverage, and supply availability differ between the two. This page focuses specifically on the weight loss context and does not provide treatment guidance.
Last reviewed 2026-07-08 · Next review 2026-08-07
Sermorelin and tesamorelin are both synthetic analogs of growth hormone-releasing hormone (GHRH) that stimulate endogenous GH secretion via pituitary GHRH receptors. Despite their mechanistic similarity, their regulatory trajectories diverge sharply. Tesamorelin (Egrifta) is FDA-approved for the reduction of excess visceral abdominal fat in HIV-infected patients with lipodystrophy, backed by a Phase 3 trial published in the New England Journal of Medicine (Falutz et al., 2010). Sermorelin (Geref) was previously FDA-approved as a diagnostic agent for pediatric growth hormone deficiency but was discontinued by the manufacturer and is no longer commercially available under an FDA-approved brand; it is now compounded by telehealth clinics for off-label adult use. This comparison documents their overlapping mechanism, divergent evidence bases, and distinct regulatory and availability landscapes.
Last reviewed 2026-07-08 · Next review 2026-08-08
Tirzepatide (Mounjaro/Zepbound, Eli Lilly) and semaglutide (Ozempic/Wegovy/Rybelsus, Novo Nordisk) are both increin-based injectable drugs FDA-approved for Type 2 diabetes and chronic weight management. Semaglutide is a single GLP-1 receptor agonist; tirzepatide is a dual GIP/GLP-1 receptor agonist. Both have published Phase 3 trial data and large-scale cardiovascular outcomes trials. Tirzepatide has demonstrated greater weight loss and A1C reduction in head-to-head trials (SURPASS-2, SURMOUNT-5) versus semaglutide, though the trials differ in populations and protocols. Both are widely prescribed and available via telehealth platforms. This page documents mechanistic, regulatory, and clinical trial differences without recommending either drug.