Hormones & metabolism IGF-1 (recombinant)
Mecasermin
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- FDA approval
- An FDA-approved product contains this peptide
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
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Key takeaway
Mecasermin (sold as Increlex) is recombinant human insulin-like growth factor 1 (IGF-1), used to treat children who cannot make IGF-1 or cannot respond to growth hormone. It supplies the growth signal that growth hormone would normally produce, bypassing the missing step. It has been FDA-approved in the U.S. since 2005 and is given as a twice-daily injection timed around meals.
At a glance
- What it is
- Recombinant human insulin-like growth factor 1 (IGF-1)
- Approved for
- Growth failure in children with severe primary IGF-1 deficiency or growth hormone gene defects with antibodies to growth hormone
- Key fact
- In the pivotal study, treatment raised average height velocity from about 2.8 to 8.0 cm per year in the first year
- Route
- Subcutaneous injection, twice daily
- Evidence strength
- FDA approved
Summary
Mecasermin is recombinant IGF-1, FDA-approved since 2005 for children with severe primary IGF-1 deficiency. Learn how it works and who it is for.
What is mecasermin?
Mecasermin, sold under the brand Increlex, is a laboratory-made copy of insulin-like growth factor 1 (IGF-1), the hormone that actually carries out much of growth hormone's work in the body. Growth hormone stimulates the liver to make IGF-1, and IGF-1 then drives tissue growth. Children who cannot make IGF-1, or who cannot respond to growth hormone, do not grow normally; mecasermin provides the IGF-1 directly. It was approved in the United States in 2005.
How does mecasermin work?
Mecasermin is identical to natural IGF-1 and binds the IGF-1 receptor on cells throughout the body, directly delivering the growth-promoting signal that would normally follow growth hormone action. In children with severe primary IGF-1 deficiency, growth hormone is present but the body cannot generate IGF-1 in response, so replacing IGF-1 restores growth that growth hormone therapy alone cannot achieve.
Because IGF-1 shares actions with insulin, mecasermin can lower blood sugar, which is why it is dosed shortly before or after a meal. In the pivotal study of children with growth hormone insensitivity, IGF-1 raised average height velocity from about 2.8 cm per year at baseline to 8.0 cm per year in the first year of treatment.
Is it FDA-approved?
Editor’s note
Status: Yes. Mecasermin was approved by the FDA in 2005 for growth failure in children with severe primary IGF-1 deficiency, or with growth hormone gene deletion who have developed neutralizing antibodies to growth hormone. It is given as a twice-daily subcutaneous injection.
Category: FDA-approved · Primary body area: Hormones & metabolism
Yes. Mecasermin was approved by the FDA in 2005 for growth failure in children with severe primary IGF-1 deficiency, or with growth hormone gene deletion who have developed neutralizing antibodies to growth hormone. It is given as a twice-daily subcutaneous injection.
What is mecasermin prescribed for?
Mecasermin is prescribed for children with severe primary IGF-1 deficiency, a rare condition in which the body cannot produce IGF-1 despite normal or high growth hormone. It is not a treatment for ordinary growth hormone deficiency, which is treated with growth hormone itself.
What are the side effects?
According to the prescribing information, common side effects include:
- Low blood sugar, which is why dosing is tied to meals
- Injection-site changes such as fatty lumps
- Enlargement of the tonsils or adenoids
More serious considerations include:
- Increased pressure around the brain (intracranial hypertension)
- Slipped hip growth plate and worsening scoliosis
- Cancers, which have been reported in children treated with mecasermin
Mecasermin is contraindicated once the growth plates have closed and in children with cancer or a history of cancer.
Sources: FDA prescribing information for Increlex; a long-term study of IGF-1 therapy (Chernausek et al., Journal of Clinical Endocrinology and Metabolism, 2007, DOI: 10.1210/jc.2006-1610), indexed on PubMed. This document is educational and does not constitute medical advice.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
- [2]
approved (PDF)
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