Gout is one of the most painful forms of arthritis. It's estimated about 3 percent of the 3 million adults who suffer from gout do not respond to other treatments or cannot take alternatives for various reasons.
Wednesday, the FDA approved the use of Krystexxa for adults who fit that category.
It is given every two weeks intravenously. Clinical trials show the drug lowered uric acid levels and reduced deposits of uric acid crystals in joints and elsewhere.
Some patients did experience severe allergic reactions, nausea and other side effects.
The drug is expected to be available by prescription later this year and will carry a black box warning regarding allergic reactions.