The US Food and Drug Administration (FDA) has granted approval for Johnson & Johnson’s Stelara (ustekinumab), a new drug to treat the immune system disorder psoriasis.

Stelara is a monoclonal antibody that mimics the body’s own antibodies to block the action of two proteins that contribute to the overproduction of skin cells and inflammation.

The effectiveness of the treatment was established through three phases of clinical trials involving 2,266 patients.

FDA Centre for Drug Evaluation and Research Office of Drug Evaluation III director Julie Beitz said that this approval provides an alternative treatment for people with plaque psoriasis.

“This is an important new treatment for a disease that can cause significant physical discomfort from pain and itching and result in poor self-image for people who are self-conscious about their appearance,” Beitz said.

The FDA requires a risk evaluation and mitigation strategy for Stelara as the new treatment, which reduces the immune system’s ability to fight infections, has been reported to lead to serious infections – some requiring hospitalisation.

Stelara is manufactured by Centocor Ortho Biotech, a wholly owned subsidiary of Johnson & Johnson.