LGD-4033

LGD-4033, also called ligandrol and registered in one trial under the company code VK5211, is a non-steroidal compound acting on the androgen receptor. It has the cleanest human trial record of the eleven: a placebo controlled phase 1 in healthy men, and a phase 2 in people recovering from a hip fracture that posted real statistics. It holds no medicines approval anywhere the searches looked.

It acts selectively on the androgen receptor. In the 21 day phase 1 what moved was lean body mass, up an average 1.21 kg at the top dose, while leg press strength, stair climbing and appendicular muscle mass did not separate from placebo.

Muscle gain, and recovery after injury. The hip fracture trial is the closest thing to that second use, and its own registry record carries no functional secondary outcome at all, so in people recovering from a broken hip nothing about function was registered to be measured.

The trial doses and the market doses are not the same order of magnitude, and one guide page bridges the gap with a sentence that does not survive checking: it tells readers clinical trials support up to 222 mg a day for 14 days. Its citation list has two entries, and the only trial among them is the 21 day study whose highest dose was 1.0 mg.

Both halves belong together. In the 21 day phase 1 neither of the two liver enzymes on a routine blood test changed significantly at any dose; what fell instead was HDL cholesterol, triglycerides, total testosterone and the protein that carries it, all in proportion to dose and all back to baseline after the men stopped. That is the only measured recovery of the body's own testosterone the class page research found for any of the eleven. Against that, two published case reports name this compound on its own in severe liver injury, one of them at 10 mg a day, and a third describes it alongside RAD-140.