• Posted December 12, 2025

Experimental Drug Provides Lasting Relief For Bleeding Condition

More than half of people with a rare life-threatening bleeding condition received lasting relief from an experimental antibody treatment, clinical trial results show.

Ianalumab, a monoclonal antibody, helped patients with immune thrombocytopenia (ITP) maintain safe platelet counts without serious bleeding episodes for at least a year, according to results published Dec. 9 in The New England Journal of Medicine.

The drug achieved that after four monthly doses, researchers reported.

“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,” lead researcher Dr. Adam Cuker, clinical director of the University of Pennsylvania Blood Disorders Center, said in a news release.

ITP is an autoimmune disease that causes the body’s immune cells to attack platelets, the blood cells responsible for clotting, researchers said in background notes. It affects about 50,000 people in the U.S.

The disease causes abnormal bleeding from the skin and mucous membranes, including nosebleeds, gum bleeding and heavy menstruation. Patients might also suffer from easy bruising and fatigue.

ITP patients who develop low platelet counts or suffer severe bleeding initially are treated with steroids, researchers said. After that, the U.S. Food and Drug Administration (FDA) has approved three drugs for ITP, but all require that people take daily pills or weekly injections for the rest of their lives.

“As a hematologist, I’m glad that we have effective therapies for ITP, but they’re not necessarily ideal for chronic disease management or long-term quality of life,” Cuker said.

Ianalumab works by targeting the immune cells that generate platelet-attacking antibodies, researchers said.

For the new trial, researchers recruited 152 people with ITP and randomly assigned them to one of three groups. The first two groups got either a high or low dose of ianalumab, while the third group received a placebo.

The patients received their doses once a month for four months. Everyone also received eltrombopag, a drug that spurs platelet production, for up to four months.

Results showed that 54% of people who got a higher dose of ianalumab and nearly 51% of those who got the lower dose were likely to maintain normal platelet counts for a year, compared to only 30% of those receiving a placebo.

When platelet counts were measured at six months — two months after the last dose of ianalumab — 62% of the high-dose patients had stable platelet counts, versus 39% in the placebo arm.

Additional clinical trials for ianalumab are ongoing, including studies of other autoimmune disorders, researchers said. Researchers will continue to follow the patients from this trial to track their long-term response.

"We’re looking forward to seeing if the treatment-free responses in this study extend out even further,” Cuker said. “Improving the long-term reality of living with ITP is not something we’ve been able to think about before. The goal has always been to improve platelet counts or reduce the risk of bleeding, but this research is ushering in a new era of hope for patients with ITP.”

Ianalumab is not yet FDA-approved for patients, researchers noted.

Novartis, the developer of ianalumab, funded the clinical trial.

More information

The Cleveland Clinic has more on immune thrombocytopenia.

SOURCE: University of Pennsylvania, news release, Dec. 9, 2025