The Food and Drug Administration on Wednesday approved an injectable drug from GlaxoSmithKline PLC to treat severe asthma attacks.

The agency cleared Nucala for patients 12 years and older who cannot control their asthma with more conventional drug options.

The new drug joins four other respiratory medicines Glaxo has launched since 2013 as it tries to re-invigorate its respiratory franchise.

Nucala is injected every four weeks by a health care professional in the arm, thigh or abdomen. The genetically engineered antibody is grown in cells from Chinese hamsters and works by reducing levels of white blood cells that contribute to asthma.

Side effects reported in company testing included headache, injection site reactions, back pain, and fatigue. Hypersensitivity reactions can occur within hours or days of injection with Nucala.

Drugs for asthma and other breathing disorders make up Glaxo’s largest drug segment.