SS-31 (Elamipretide) Half-Life Calculator
SS-31, also called elamipretide, is a tetrapeptide that concentrates in the inner mitochondrial membrane by binding cardiolipin. It has been through clinical trials, which places it further along than most compounds discussed alongside it.
Half-life 4 hours · peaks at 45 min
Every 24 hours.
Half-life
Left at next dose
SS-31 (Elamipretide) · once daily · levels plateau after ~20 hours
Steady-state peak
1.01 mg
Steady-state trough
0.02 mg
Accumulation
None
At once daily, each dose has essentially cleared before the next one — levels don't accumulate, they repeat the same rise and fall. Clearance after a dose takes about 20 hours.
This is a modelled estimate of relative levels from published half-life and time-to-peak figures — not a measured blood concentration. Individual pharmacokinetics vary.
Based on a published SS-31 (Elamipretide) half-life of about 4 hours. The chart models RELATIVE levels from a unit dose — enter your own figures to see the shape. It is not a dose recommendation.
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What a 4 hours half-life means in practice
A half-life of 4 hours against once daily dosing means each dose has essentially cleared before the next arrives. That shapes the curve in three ways:
1. One half-life
Half the dose is gone after 4 hours. After two half-lives 25% remains, after three 12.5%.
2. What's left at the next dose
Dosing once daily means the next dose lands 24 hours later, with about 2% of the previous one still present.
3. Accumulation and plateau
Almost nothing carries over, so levels don't accumulate — each dose repeats the same rise and fall, clearing in about 20 hours.
Worked example
SS-31 (Elamipretide) has a half-life of 4 hours. Dosing once daily, the next dose arrives 24 hours later with about 2% of the previous one still on board. That's little enough that levels don't build up: each dose rises and falls on its own, clearing in about 20 hours.
Targeting rather than circulating
Most compounds distribute broadly and act wherever their receptor happens to be. SS-31 is designed to concentrate in a specific place: it binds cardiolipin, a phospholipid found in the inner mitochondrial membrane, which localises it to mitochondria at far higher concentration than the plasma level would suggest.
That distinction matters for reading its pharmacokinetics. A plasma half-life describes how long the compound circulates, not how long it remains where it accumulates, and for a compound designed to concentrate in a specific membrane the two can diverge considerably. It has been investigated in clinical trials for mitochondrial disease indications.
Frequently asked questions
This calculator is provided for informational and educational purposes only and is not medical advice. Always confirm dosing with a qualified healthcare professional and double-check your own measurements before administering anything.
Built by the Pep AI team.