DOSEGUY

GSK-2881078

guinea pig

Also seen as: GSK2881078, GSK 2881078, GSK

The Dose Guy’s verdict
Sep 1, 2026
3 sources

GSK-2881078 is the rare SARM with real pharmaceutical trial data: first-in-human, phase 1b in older adults, phase 2A in COPD, a genuine lean-mass signal. And then GSK shelved it. My read: liver enzyme bumps, HDL drops, two cases of rhabdomyolysis in a clinical trial, and not enough upside to continue. If you want a SARM with community mileage, ostarine and ligandrol have years of it. GSK-2881078 has receipts but no road.

Would I take it?Not when pharma walked away.

What it is

An oral nonsteroidal SARM developed by GlaxoSmithKline for age-related muscle wasting. It reached further into clinical development than most SARMs ever do: proper dose-escalation, randomized placebo-controlled design, a disease-population trial in COPD. It sits in an odd spot: better studied than most SARMs by pharma standards, basically unknown to the gym community, and abandoned by the company that made it.

What the research shows

More published human data than most SARMs. Still not enough for GSK to continue:

GSK-2881078 produced dose-dependent increases in lean mass in healthy older men and postmenopausal women. Every tested dose beat placebo. Women showed a greater lean-mass response at lower doses than men.JCEM 2018 · phase 1b · dose-escalation
In men with COPD, the absolute leg-strength difference versus placebo was 11.8 kg at 90 days, with a 90% CI of -0.5 to 24.0 kg, which crossed zero. The relative strength gain, 7.0% (90% CI 0.5% to 13.6%), did clear it. Patient-reported outcomes showed no change versus placebo with concurrent home exercise.Thorax 2023 · phase 2A · n=97
A systematic safety review reported rhabdomyolysis in two people exposed to GSK-2881078 in a clinical trial.J Xenobiotics 2023 · systematic review · 33 studies
No phase 3 trial of GSK-2881078 has been published. The program stopped before it got there.as of Aug 2026

Realistic protocols

Almost nobody in the physique community runs GSK-2881078. The trial loaded twice daily for the first three days, then dropped to once daily for up to 53 days, and the long elimination means levels build for weeks. Women responded at lower doses than men in the phase 1b. If you have sourced this compound and intend to try it, treat the trial’s dose range as your ceiling, not your floor. Bloodwork before and after: liver enzymes and lipids are the known signals. Drinking on this compound deserves thought, given the transaminase elevations the trials documented. PCT planning applies the same as any suppressive SARM. A third-party COA is non-negotiable for a compound this niche. Every SARM is WADA-prohibited in tested sport.

Side effects

Better characterized than most SARMs, because the trials actually measured them:

monitorTransient liver enzyme elevations, documented in both the phase 1b and the COPD trial. Reversible, but real.
monitorHDL cholesterol drops, a main finding in the COPD trial. Reversed after stopping.
monitorRhabdomyolysis in two trial participants. Rare, but a reason the bar for running this compound is high.
unknownNo long-term safety data. The program stopped before anyone ran it beyond a few months.

Where to buy

No live listings from tracked vendors right now.