Elamipretide, a prescription drug given by daily injection that targets the energy-producing parts of cells, is approved only for one rare inherited disorder and draws interest for restoring energy in aging muscle. It helped old mice, but in older people one dose only briefly raised muscle energy, and larger trials in muscle and heart disease found no benefit. Injections commonly irritate the skin; decades-long effects are unknown. (Full Review)
| Marker | Target | Why |
|---|---|---|
| eGFR (estimated glomerular filtration rate) | ≥60 mL/min/1.73 m² (standard reference range) | Safety check: sets the dose |
| Absolute eosinophil count | 0.0–0.5 × 10³/µL (standard reference range) | Safety check: the drug raises it |
| 6-minute walk distance | No established target; track change from own baseline | Expected to change: main trial endpoint |
| Knee-extensor strength | No established target; track change from own baseline | Expected to change: basis of approval |
Cadence: Baseline eGFR, eosinophil count and function tests before starting; blood count at 4 weeks and 3 months; eGFR at 3 months, then every 6–12 months; function tests at 3 and 6 months; injection sites, rash or cough checked daily during the first months