Nov 05, 2015 09:06 AM EST By Rashmi Kalia, UniversityHerald Reporter

The FDA has approved GlaxoSmithKline's Nucala (mepolizumab) as an add-on maintenance treatment of severe eosinophilic asthma in patients at least 12 years old, Seeking Alpha reports.

The commercial launch of the drug will now start as soon as possible. The FDA clearance is the first regulatory approval anywhere in the world.

Patients suffering from asthma will receive Nucala in addition to their normal medications for severe asthma.

"This approval offers patients with severe asthma an additional therapy when current treatments cannot maintain adequate control of their asthma," Dr. Badrul Chowdhury, director of the FDA's pulmonary, allergy and rheumatology products division, said in a statement, Yahoo News reports.

Analysts expect the drug to generate annual sales of $756 million by 2020, according to Thomson Reuters data.

Nucala is the first and only biologic cleared by the FDA that targets interleukin-5. Interlukin-5 OR il-5 has an important role in the regulation of white blood cells, that increase in number in patients suffering from asthma.

The dosage of Nucala is a100 mg fixed dose subcutaneous injection that is administered every four weeks to the patient.

However, the inclusion of patients as young as 12 years among the patients who can be administered Nucala is a surprise since the FDA's advisory committee voted 10-4 against the use of Nucala in adolescents.

The FDA voted 14-0 in favor of approval in adults.

Nucala is not approved for the treatment of other eosinophilic conditions. It is also not administered for the relief of acute bronchospasm or status asthmaticus..

In controlled trials, patients who received Nucala had fewer asthma attacks that required hospitalization and experienced longer breaks between asthma attacks, Wall Street Journal reports.

The most common reported side effects of Nucala include redness, swelling and itching in the injection area, back pain and fatigue.

The company also said patients should consider a varicella vaccination, if medically appropriate, before starting therapy with Nucala, Wall Street Journal reports.

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