Comparison
Semaglutide vs Thymosin Alpha-1
Side-by-side of Semaglutide and Thymosin Alpha-1. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Semaglutide
Semaglutide for weight loss: GLP-1 agonist (Ozempic, Wegovy) drives 15-17% mean loss at 2.4 mg/week in STEP trials. Watch lean-mass loss.
Thymosin Alpha-1
Thymosin alpha-1 peptide (Zadaxin, thymalfasin): 28-amino-acid TA1 immunomodulator. Dosing, T-cell effects, hepatitis B and HCV adjunct evidence.
Effects at a glance
Semaglutide
- •Long-acting GLP-1 receptor agonist with a ~7-day half-life that supports once-weekly subcutaneous dosing
- •STEP trials reported ~15 to 17% mean body-weight loss at 2.4 mg/week over 68 weeks in adults with obesity
- •Lowers HbA1c by ~1.0 to 1.8 percentage points in type 2 diabetes versus placebo
- •SELECT trial showed reduced major cardiovascular events in adults with prior CVD and overweight or obesity
- •Up to 25 to 40% of weight lost can be lean mass; pairing with resistance training and protein intake mitigates this
- •GI effects (nausea, vomiting, constipation) drive most discontinuations and ease with slow titration
Thymosin Alpha-1
- •28-amino-acid synthetic peptide identical to thymic-derived immunomodulator
- •Approved in over 35 countries as Zadaxin for hepatitis B, hepatitis C adjunct, and immune support
- •Not FDA approved in US; compounded by 503A/503B pharmacies for off-label immune support
- •Modulates T-cell maturation, NK activity, and Th1 polarization in immunocompromised states
- •Standard label dose: 1.6 mg subcutaneously twice weekly
- •Cleanest safety profile in the peptide class with hundreds of regulated trials behind it
Side-by-side
| Attribute | Semaglutide | Thymosin Alpha-1 |
|---|---|---|
| Category | pharmaceutical | peptide |
| Also known as | Ozempic, Wegovy, Rybelsus | Talpha1, Ta1, Zadaxin, Thymalfasin |
| Half-life (hr) ↗ | 168 | 2 |
| Typical dose (mg) ↗ | 2.4 | 1.6 |
| Dosing frequency | weekly (SC); daily (oral Rybelsus) | 2x weekly |
| Routes | subcutaneous, oral | subcutaneous, intramuscular |
| Onset (hr) | 24 | 24 |
| Peak (hr) | 72 | 168 |
| Molecular weight | 4113.58 | 3108.32 |
| Molecular formula | - | C129H215N33O55 |
| Mechanism | Long-acting GLP-1 receptor agonist; potentiates glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and acts on hypothalamic satiety centers. | Synthetic peptide modulator of innate and adaptive immunity. Promotes T-cell maturation and CD4/CD8 production, modulates Th1/Th2 balance, stimulates NK cell activity, and modulates TLR2/TLR9 signaling in dendritic cells. |
| Legal status | Prescription only (FDA-approved, EMA-approved) | Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List |
| WADA status | allowed | unknown |
| DEA / Rx | Rx only (not a controlled substance); FDA-approved for type 2 diabetes (2017) and chronic weight management (2021) | Rx only via international approval or US compounding (no controlled-substance schedule) |
| Pregnancy | Not recommended; discontinue 2 months before planned pregnancy | Not recommended; insufficient data |
| CAS | 910463-68-2 | 62304-98-7 |
| PubChem CID | 56843331 | 16130571 |
| Wikidata | Q27089394 | Q913854 |
Safety profile
Semaglutide
Common side effects
- nausea
- vomiting
- diarrhea
- constipation
- decreased appetite
- injection-site reactions
- fatigue
Contraindications
- personal or family history of medullary thyroid carcinoma
- multiple endocrine neoplasia type 2
- pregnancy
- history of pancreatitis (use caution)
Interactions
- insulin: additive hypoglycemia risk; insulin dose typically reduced(major)
- sulfonylureas (glipizide, glyburide): hypoglycemia risk, sulfonylurea dose often reduced(major)
- oral medications (general): delayed gastric emptying can alter absorption kinetics(moderate)
- warfarin: monitor INR due to altered absorption(moderate)
Thymosin Alpha-1
Common side effects
- mild injection-site irritation (rare)
- transient mild fatigue (rare)
- occasional headache (rare)
Contraindications
- pregnancy
- lactation
- active organ transplant rejection therapy
- systemic immunosuppression for autoimmune disease (relative)
- severe active autoimmune disease (caution)
Interactions
- interferon-alpha: additive immune effect; used clinically in approved combination protocols(minor)
- calcineurin inhibitors (cyclosporine, tacrolimus): theoretical destabilization of immunosuppression; avoid(major)
- antimetabolites (azathioprine, mycophenolate): theoretical destabilization of immunosuppression; avoid(major)
- vaccine administration: may augment vaccine response in elderly or immunocompromised; coordinate with clinician(minor)
Which Should You Take?
Semaglutide and Thymosin Alpha-1 score evenly on the criteria we weight (goal breadth, legal accessibility, evidence depth). The conditionals below should drive the decision more than any aggregate score.
- → If your priority is metabolic health and glucose control, pick Semaglutide.
- → If your priority is fat loss, pick Semaglutide.
- → If your priority is immune support, pick Thymosin Alpha-1.
- → If your priority is post-training recovery, pick Thymosin Alpha-1.
Edge case: If you cannot self-administer injections, Semaglutide is the only oral option in this pair.
Default choice: either is defensible. Semaglutide edges out on goal breadth + legal accessibility; Thymosin Alpha-1 is the right call if your priority sits in the goals listed above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Semaglutide and Thymosin Alpha-1?
Semaglutide and Thymosin Alpha-1 differ in category (pharmaceutical vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Semaglutide or Thymosin Alpha-1?
Semaglutide half-life is 168 hours; Thymosin Alpha-1 half-life is 2 hours.
Can you stack Semaglutide with Thymosin Alpha-1?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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