A recent clinical trial has revealed promising results for patients suffering from primary immune thrombocytopenia (ITP), an autoimmune disorder that can lead to severe bleeding. More than half of the participants who received the experimental monoclonal antibody ianalumab were able to maintain safe platelet counts without serious bleeding episodes for at least one year. These findings were published in the New England Journal of Medicine and presented at the 67th American Society of Hematology Annual Meeting in Orlando, Florida.
ITP occurs when the immune system mistakenly attacks platelets, the cells essential for blood clotting. The condition affects approximately 50,000 people in the United States and can manifest at any age. Symptoms include abnormal bleeding from the skin and mucous membranes, such as nosebleeds and heavy menstruation. In severe cases, low platelet counts can result in easy bruising and fatigue. While some individuals with ITP do not require treatment, others with persistent low platelet counts or severe bleeding typically begin with steroid therapy. However, when steroids are ineffective or difficult to taper, alternative treatments become necessary.
Currently, there are three FDA-approved second-line therapies for ITP, but they usually entail lifelong treatment, often in the form of daily pills or weekly injections, each carrying potential side effects and financial burdens. Lead author Adam Cuker, MD, MS, who serves as the section chief for Hematology at the Perelman School of Medicine, emphasized the need for more effective long-term solutions. “This study shows that prolonged, durable responses to ITP treatment, without the need for ongoing therapy, are possible—and that’s a huge advantage for patients,” he stated.
Study Design and Results
The double-blind, multicenter clinical trial known as the VAYHIT2 study involved 152 adult patients with ITP, who were randomized into three groups: a higher dose of ianalumab (50 patients), a lower dose (51 patients), and a placebo (51 patients). Ianalumab targets the B-cell-activating factor (BAFF) receptor, leading to a depletion of autoreactive B cells that produce anti-platelet antibodies responsible for ITP.
Participants had previously experienced relapses after steroid treatment or had not responded to steroids at all. Ianalumab was administered intravenously once a month for four months, but to facilitate the study’s objectives, all patients also received eltrombopag, an existing oral medication approved for second-line ITP treatment. While eltrombopag is typically taken indefinitely, patients were instructed to taper off during the study.
The primary endpoint measured was “time to treatment failure,” which was defined as a low platelet count, the need for additional ITP therapy, inability to taper or discontinue eltrombopag, or death. The results indicated that the estimated probability of avoiding treatment failure at 12 months was 54.2% in the high-dose ianalumab group and 50.5% in the low-dose group, compared to only 30% in the placebo group. Furthermore, six months post-treatment (two months after the last dose of ianalumab), 62% of patients in the high-dose group maintained stable platelet counts, while only 39.2% of those in the placebo group achieved similar results.
Future Outlook and Ongoing Research
Although ianalumab is not yet approved by the FDA, additional clinical trials are underway to explore its efficacy in treating other autoimmune conditions. Researchers plan to continue monitoring the patients involved in this study to assess long-term responses to treatment. Dr. Cuker expressed optimism about the future for ITP patients: “Improving the long-term reality of living with ITP is not something we’ve been able to think about before. This research is ushering in a new era of hope for patients with ITP.”
The study received funding from Novartis, highlighting the ongoing collaboration between academia and pharmaceutical companies to advance treatment options for challenging medical conditions. For more detailed information, refer to the publication “Ianalumab plus Eltrombopag versus Placebo plus Eltrombopag in Immune Thrombocytopenia” in the New England Journal of Medicine (2025). DOI: 10.1056/NEJMoa2515168.
