Warm autoimmune hemolytic anemia, or wAIHA (pronounced “wah-ha”), is a rare, potentially life-threatening disease, with about one in 8,000 people living with the condition. It occurs when the body’s immune system produces autoantibodies—pathogenic antibodies—that attack and destroy healthy red blood cells.
Red blood cells have the vital job of delivering oxygen throughout the body, and antibodies normally protect the body from harmful invaders like bacteria and viruses. But when someone has wAIHA, immunoglobulin G (IgG) antibodies (the most common type of antibody) mistakenly mark red blood cells for destruction. This process is called hemolysis.
“Those antibodies are leading to prematurely destroying the red blood cells, sometimes faster than the body can produce new red blood cells,” explains Ludovic de Beaucoudrey, Ph.D., Vice President, Global Medical Affairs, Autoantibody at Johnson & Johnson. “This leads to anemia, which hinders oxygen delivery to every organ in the body.”
Anemia, a condition marked by low levels of red blood cells, in turn causes a range of debilitating symptoms. The term “warm” means that the antibodies bind to and attack red blood cells at normal body temperatures, as opposed to the mechanism behind other types of autoimmune hemolytic anemia, says de Beaucoudrey.
Here’s what to know about wAIHA, including Johnson & Johnson’s commitment to advancing newl treatment options for patients with this disease.
The two types of wAIHA
Primary wAIHA—which accounts for about 60% of cases—doesn’t have an identifiable cause.
Experts classify wAIHA as secondary when it is caused by an underlying condition, such as a blood cancer, infection or another immune-mediated disease. It can also be associated with some medications.
Either type of wAIHA can strike anyone at any age. However, the incidence of the disease becomes more common after age 50, and slightly more women than men develop wAIHA.
What are the symptoms of wAIHA?
Without enough red blood cells bringing oxygen to the body, anemia will develop and leave a person feeling depleted of energy. As a result, profound fatigue is the most common symptom of wAIHA.
“When anemia is severe, patients describe it as being unable to get out of bed,” says de Beaucoudrey. “If they can get up and take a shower, that can be all they do—they’re done for the day.” They may feel weak all over, too tired to cook a meal to eat and unable to start or finish tasks. They may be forced to limit social interactions and need extra sleep during daytime hours.
Along with fatigue, signs and symptoms can include dizziness, shortness of breath (especially with exertion), increased heart rate, yellowing of the skin and eyes, pale skin, chest pain and dark urine.
For many patients, wAIHA is recurrent; they experience periods of remission and then relapses in which symptoms return. About two-thirds of patients have some type of relapse, says de Beaucoudrey. On top of dealing with symptom recurrences, relapses can take an emotional toll, leading to anxiety and depression.
“Patients may suffer from significant physical effects as well as emotional effects,” he explains. “They have the burden of wondering if and when the condition will worsen and how severely or suddenly, usually with little warning.”
How wAIHA is diagnosed
The first step toward a diagnosis is having a healthcare provider check a person’s complete blood count, which measures red and white blood cell levels. A blood count will also show whether hemoglobin is low, which is a hallmark sign of anemia.
If anemia is discovered, clinicians will look into all possible causes, such as iron deficiency, says de Beaucoudrey. Tests can distinguish hemolysis and then more blood tests will be ordered. “Specifically, the Direct Antiglobulin Test can uncover if IgG antibodies are attacking red blood cells and thus can help confirm wAIHA,” he says.
Physicians then do further testing to determine the presence of an associated condition, like lupus or blood cancer, which could be the underlying cause of wAIHA. This helps patients get the appropriate treatment for those diseases, and that often improves symptoms, says de Beaucoudrey. If wAIHA remains undiagnosed, anemia can become severe, compromising blood oxygenation in organs and tissues.
Treatment for wAIHA
wAIHA is classified as a rare disease, which means it affects so few people that it’s difficult to find enough study subjects to conduct clinical trials on the effectiveness of potential treatments. “Because studies are challenging to conduct, clinicians have few studies upon which to base treatment decisions,” says de Beaucoudrey.
In the absence of an FDA- or EMA-approved therapy for wAIHA, healthcare providers typically try solutions that help manage symptoms by increasing hemoglobin levels and decreasing hemolysis. One first-line treatment is high-dose corticosteroids, a type of anti-inflammatory medication.
B-cell depletion therapy is another option. B cells are white blood cells that can create antibodies that attack red blood cells.
Some patients with wAIHA may have their spleen removed, as the spleen is where antibodies destroy red blood cells. Other treatments include taking immunosuppressant drugs or receiving blood transfusions. But newer options that can provide sustained disease control, have a demonstrated safety profile and target the specific mechanisms of the disease are needed, says de Beaucoudrey.
Johnson & Johnson completed the double-blind portion of a clinical study for a targeted treatment for wAIHA. Based on the study findings, the company submitted an application to the U.S. Food and Drug Administration in February 2026 seeking approval of its investigational treatment in wAIHA. Approval was granted in late August 2026.
As part of its research into wAIHA, Johnson & Johnson has also partnered with patients and amplified their voices with the goal of understanding the personal impact of this disease. The company created a patient council to learn from people living with wAIHA about their diagnosis and treatment journeys, plus how the condition affects their day-to-day lives.
Immune-mediated diseases, including those classified as rare diseases, have long been a focus for Johnson & Johnson, says de Beaucoudrey. That focus includes the 80-plus autoantibody-driven conditions severely impacting nearly 240 million people worldwide.
“People living with wAIHA have faced a significant unmet need, with no approved therapy indicated specifically for their disease until now,” he says. “At Johnson & Johnson, we are proud to help advance research in this rare, immune-mediated condition and support progress toward solutions that may make a meaningful difference for patients and the healthcare providers who care for them.”
This is an update to a story originally published on June 12, 2025
