Corticotropin (ACTH): effects, uses and side effects
Clinical review pending
Corticotropin stimulates the body's steroid production and is used for certain inflammatory and hormonal conditions. An overview of its effects, US approval and risks.
Corticotropin, also called ACTH, prompts the adrenal glands to produce cortisol and related steroid hormones. As a medicine, it is used for conditions including infantile spasms, a severe form of seizures in infancy, and acute relapses of multiple sclerosis. Its effects and side effects partly resemble those of corticosteroids. The approvals described here concern the US.
What is corticotropin?
Corticotropin’s full name is adrenocorticotropic hormone, abbreviated ACTH. The pituitary gland produces this hormone, which consists of 39 amino acids. It stimulates the adrenal glands to produce cortisol and related steroid hormones.
One product is Acthar Gel, formerly H.P. Acthar Gel. It contains purified porcine corticotropin in a long-acting gelatin preparation. Purified Cortrophin Gel is also marketed in the US. Corticotropin is one of the oldest biological medicines: its use dates back to the early 1950s. It is used for various inflammatory and hormonal conditions.
How does corticotropin work?
Corticotropin stimulates steroid production and also acts directly on immune cells and other cells. It does this by binding to different melanocortin receptors, which are binding sites on the cell surface:
| Mode of action | Binding site | Effect |
|---|---|---|
| Classical effect | Melanocortin-2 receptor on the adrenal cortex | Stimulates the adrenal glands to produce and release cortisol, corticosterone and other steroid hormones. Much of the anti-inflammatory effect arises through this stimulation of the body’s own steroid production. |
| Direct effect | Melanocortin receptors on immune cells and other cells | Inhibits inflammation and influences the immune response independently of steroids as well. This influence is called immunomodulation. |
These two pathways may help explain why corticotropin continues to be used in certain treatment settings. The mechanism alone does not establish an advantage over synthetic steroids. In a controlled trial of infantile spasms, high-dose ACTH stopped spasms more effectively than prednisone. This comparison concerns the treatment studied in that trial. 1
Because corticotropin stimulates the body’s own steroid production, side effects similar to those of corticosteroids can also occur.
Is corticotropin FDA-approved?
Yes. Acthar Gel has been approved by the US Food and Drug Administration since 1952. Specific approval for infantile spasms followed in 2010. The US prescribing information lists numerous uses; corticotropin has a long history of use and acts much like steroids in many respects. 2
What is corticotropin prescribed for?
In the US, corticotropin is prescribed for the following conditions and treatment settings:
- Infantile spasms in young children
- Acute relapses of multiple sclerosis
- Nephrotic syndrome
- Short-term adjunctive treatment for various rheumatic diseases, connective-tissue diseases, skin conditions, allergic conditions, eye conditions and other inflammatory conditions, including symptomatic sarcoidosis
Its cost and steroid-like effects and side effects generally limit its use to particular treatment settings.
What side effects can occur?
The prescribing information lists the following common side effects:
- Injection-site reactions
- Fatigue
- Fluid retention and swelling
- Sleep problems and headache
- Increased blood sugar
In infants treated for infantile spasms, common side effects include:
- Infections
- Seizures
- High blood pressure
- Irritability
- Fever
More serious risks include:
- Greater susceptibility to infection because treatment suppresses the immune system
- Suppressed adrenal function, which may become apparent when treatment is stopped
- Impaired growth in children and gastrointestinal bleeding