U.S. FDA expands approval for J&J’s drug for rare blood disorder

FILE - The Johnson & Johnson headquarters in New Brunswick, New Jersey, on February 8, 2024. South African authorities have dropped an investigation into Johnson & Johnson for alleged anti-competitive practices after the company agreed not to enforce its patent on a critical TB medication, a move that should allow generic producers to make the drug at much lower prices. (AP Photo/Ted Shaffrey)

The U.S. Food and Drug Administration has approved the expanded use of Johnson & Johnson’s drug to treat a rare blood disorder, the company said on Monday.

The approval makes Imaavy the first treatment cleared for warm autoimmune hemolytic anemia, or wAIHA, and covers patients aged 12 and older who are currently or were previously treated with steroids.

The life-threatening disease causes the immune system to destroy red blood cells, leading to severe anemia, fatigue, blood clots and kidney failure.

Imaavy blocks a protein that keeps harmful antibodies in the bloodstream, lowering their levels while preserving other immune functions. The drug is infused into a vein every four weeks at a dose based on weight.

“Imaavy was able to demonstrate patients can go down on their steroids and still maintain that clinical response. Those are really important advances for patients,” Johnson & Johnson’s global immunology head David Lee told Reuters.

The approval was based on a mid-to-late-stage study of 115 adults in which about three times as many patients receiving Imaavy achieved a lasting improvement in hemoglobin levels after 24 weeks as those on placebo. Hemoglobin carries oxygen in red blood cells.

The most common side effects were swelling in the arms or legs, diarrhea and fever. Imaavy can also raise the risk of infections and cause serious allergic or infusion-related reactions, according to its prescribing information.

Lee said existing treatments also have toxicities and may not adequately control the disease. He said Imaavy improved and stabilized patients’ blood counts in the study.

About one in 8,000 people have wAIHA, with one to three new cases diagnosed annually per 100,000 people, according to Johnson & Johnson.

Imaavy was first approved in April last year to treat generalized myasthenia gravis in certain adults and patients aged 12 and older. The rare immune disorder causes muscle weakness.

(Reporting by Kunal Das, Padmanabhan Ananthan and Christy Santhosh in Bengaluru; Editing by Vijay Kishore)