Johnson & Johnson said that U. S. regulators approved its new drug for the treatment of psoriasis, called Stelara, for patients aged 18 or above with moderate to severe psoriasis.

This drug has been waiting to be approved since late 2007 and was considered to be a potential blockbuster due to its effectiveness and infrequent administration. The U. S. Food and Drug Administration (FDA) went beyond its review of the product at more than one occasion to analyze amendments to J&J's marketing application.

Wells Fargo analyst Larry Biegelsen said, "Stelara's main advantage is its more-convenient dosing". The frequency of dosage is much lesser than other drugs in the same league. It is administered by injection only once every three months compared with injections every few weeks.

An estimated sale of $130 million is predicted in 2010, growing to more than $500 million in 2013.

Psoriasis is a condition, in which itchy red plaques accumulate on the surface of the skin, is caused by an over production of skin cells. It affects about 7.5 million people in the U. S.

The chemical name of Stelara is ustekinumab, it is a monoclonal antibody that proved superior to Amgen Inc's and Wyeth's injectable Enbrel in a study.

It tames two immune system proteins called interleukin-12 (IL-12) and interleukin -23 (IL-23) which is related to inflammation.

During all studies it was received well with mild side effects in some of them which did not require any adjustments in the medicine. J&J later warned that this drug has been linked to some serious infections that may increase the risk of cancer.