The U.S. Food and Drug Administration (FDA) has approved the expanded use of Johnson & Johnson’s drug Imaavy to treat a rare blood disorder.
According to the Company the approval makes Imaavy the first treatment cleared for warm autoimmune haemolytic anaemia (wAIHA), covering patients aged 12 and older who are currently receiving or have previously received steroids.
wAIHA is a potentially life-threatening condition in which the immune system destroys red blood cells, leading to severe anaemia, fatigue, blood clots and kidney failure.
Imaavy works by blocking a protein that helps keep harmful antibodies in the bloodstream, thereby lowering their levels while preserving other immune functions.
The drug is administered intravenously every four weeks, with the dosage based on the patient’s weight.
Johnson & Johnson’s Global Immunology Head, David Lee, said the drug enabled patients to reduce their reliance on steroids while maintaining clinical response.
Lee said; “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.”
The approval was based on a mid-to-late-stage study involving 115 adults, in which about three times as many patients receiving Imaavy achieved a sustained improvement in haemoglobin levels after 24 weeks compared with those given a placebo.
Haemoglobin is the protein in red blood cells responsible for carrying oxygen around the body.
The most common side effects reported were swelling in the arms or legs, diarrhoea and fever.
According to the drug’s prescribing information, “Imaavy may also increase the risk of infections and cause serious allergic or infusion-related reactions.”
Lee said “existing treatments also have toxicities and may not adequately control the disease, adding that Imaavy improved and stabilised patients’ blood counts in the study.”
According to Johnson & Johnson, about one in 8,000 people have wAIHA, while one to three new cases are diagnosed annually per 100,000 people.
Imaavy was first approved in April 2025 to treat generalised myasthenia gravis in certain adults and patients aged 12 and older.
Myasthenia gravis is a rare immune disorder that causes muscle weakness.
Reuters
