Imeglimin
aka Twymeeg
Class Glimin (tetrahydrotriazine) / first-in-class mitochondrial optimizer
Status Rx-approved (Japan, June 2021) — not approved in Western jurisdictions; import-only outside Japan
TL;DR
Japan-approved first-in-class glimin that outperforms metformin on mitochondria: partial Complex I inhibition + Complex III enhancement (no electron bottleneck), zero mGPDH interaction (no lactic acidosis risk), NAMPT → NAD+ → SIRT1/PGC-1α axis. Clinically validated: −0.87% HbA1c monotherapy, safe in CKD (where metformin is banned), 13% quadriceps strength gain independent of lean mass, erythrocyte lifespan extension via NAMPT. Polypharmacy-friendly (no CYP450 interactions). Requires import outside Japan.
Why it matters for Vitals
Imeglimin targets the mitochondria directly without metformin’s key failure modes. The muscle-quality finding (strength gain without mass change) is a unique biometric signal — likely mediated by Akt/GLUT4/mTOR optimization at constant lean mass. The NAMPT/NAD+ axis connects to the existing NMN NAD+ stack. Erythrocyte lifespan extension means HbA1c reads falsely elevated early — a confound for any Vitals user tracking glycemic control via HbA1c rather than CGM.
Key Facts
| Mechanism | Partial Complex I inhibition + Complex III enhancement; NAMPT → NAD+ → SIRT1/PGC-1α; zero mGPDH binding |
| Glycemic | −0.87% HbA1c monotherapy (TIMES 1, 24 wks); −0.92% with DPP-4i add-on |
| Renal | Safe at adjusted doses in CKD/ESRD; metformin contraindicated |
| Muscle | +13% quadriceps strength independent of lean mass (INFINITY trial) |
| Lactic acidosis | Zero — does not inhibit mGPDH (metformin’s fatal flaw) |
| CYP450 | No interactions; polypharmacy-friendly |
| Dosing | 1000 mg bid oral (standard); 500 mg bid (CKD eGFR 15–45); 500 mg daily (ESRD eGFR <15); take with meals |
| Evidence | TIMES 1/2/3 program; TWINKLE CKD study; INFINITY trial (Aging Cell 2025) |
Mechanism Summary
Dual-node electron chain modulation:
- Partial Complex I inhibition → mild electron leakage suppression (not the severe, non-competitive block of metformin)
- Complex III enhancement → clears the electron bottleneck at Qcytochrome c oxidoreductase
- Result: stable membrane potential, reduced ROS, better ATP resynthesis
NAD+/SIRT1/PGC-1α axis:
- Upregulates NAMPT → raises NAD+ → activates SIRT1/SIRT3 → deacetylates PGC-1α
- PGC-1α activation → mitochondrial biogenesis
vs. Metformin:
| Metformin | Imeglimin | |
|---|---|---|
| Complex I | Severe, non-competitive inhibition | Partial |
| Complex III | No effect | Enhanced |
| mGPDH | Inhibited | No effect |
| Lactic acidosis risk | Significant | Zero |
| Renal | Contraindicated | Safe (dose-adjusted) |
| Muscle | Neutral | +13% strength |
| CYP450 | Interactions | None |
What the current evidence suggests
- Glycemic efficacy well-established in T2DM (TIMES program, n=1000+)
- Muscle quality signal is real but requires replication in larger cohorts — currently from INFINITY trial aging/prevention cohort
- Erythrocyte lifespan extension (85.7 → ~103 days) is novel and has direct HbA1c interpretation implications
- Non-diabetic longevity applications are promising but still emerging
Stacks
| Stack | Rationale |
|---|---|
| + SLU-PP-332 | Imeglimin upregulates PGC-1α (SIRT1/AMPK); SLU-PP-332 activates ERRs requiring PGC-1α as co-activator → maximum mitochondrial biogenesis |
| + Retatrutide | Retatrutide drives aggressive fat loss; Imeglimin preserves muscle quality and prevents sarcopenia |
| + NMN NAD+ | NAMPT upregulation + NMN substrate → amplified NAD+ feedback loop |
| + GHK-Cu | GHK drives epigenetic remodeling (ATP-hungry); Imeglimin provides ATP for DNA repair/transcription |
Risks and Uncertainty
- HbA1c confound: Erythrocyte lifespan extension means HbA1c appears falsely elevated early — do not titrate based on early HbA1c readings
- Renal dose-adjustment required in CKD/ESRD
- Western regulatory approval: none (Japan only as of 2026)
- Muscle strength data: single INFINITY trial cohort, needs replication
- Long-term cardiovascular outcome trials: not yet completed
Links
- NMN NAD+ — NAD+ axis shared
- SLU-PP-332 — PGC-1α synergy
- Retatrutide — body composition pairing
- GHK-Cu — ATP support synergy
- Mitophagy — mitochondrial quality control pathway (link)
- Peptides MOC — for peptide/stack context
Source: TIMES trials · TWINKLE study · INFINITY trial (Aging Cell 2025) · Gemini Deep Research 2026-03-12