Does Mecasermin work?
Partly: follow-up of 76 children with no comparison group, and nothing on other uses.
The approval rests on open-label, uncontrolled studies: the cited 2007 report followed 76 children with severe primary IGF-1 deficiency for up to 12 years, using each child's pre-treatment growth rate as the comparison. No placebo-controlled trial exists, which is defensible for a rare pediatric disease but keeps the grade at B. The off-label uses promoted online (muscle growth, recovery) have no human trials at all. 12
The cited 2007 study pooled 76 children with severe primary IGF-1 deficiency. They were treated with mecasermin for up to 12 years. Height velocity rose from an average of 2.8 cm per year before treatment to 8.0 cm per year in the first year. It then declined in later years but stayed above baseline for up to 8 years. Final adult heights improved compared with untreated historical patients. They stayed well below population norms. 1
No randomized comparison exists. No trials have tested mecasermin for muscle growth, athletic performance or any adult approved use. Findings from children cannot be carried over to those uses. 12
Evidence checklist
- Randomised controlled trial Open-label, uncontrolled studies
- Human study over 100 people 76 children followed up to 12 years
- More than one research group Mostly sponsor-run registration studies
- Clinical outcomes, not surrogate markers Height velocity in children
- Human safety data beyond case reports Hypoglycemia rates from label data
More on Mecasermin
Citations
- Chernausek 2007, J Clin Endocrinol Metab: Long-term treatment with recombinant IGF-1 in children with severe IGF-1 deficiency doi.org
- FDA 2025: Increlex (mecasermin) prescribing information accessdata.fda.gov
Reference information only, not medical advice. Drawn from the Mecasermin article, fact-checked against the cited sources. No dosing anywhere on this site.