Ianalumab Meets Primary Endpoint in Phase 3 Trial for Primary Immune Thrombocytopenia

Ianalumab, an investigative monoclonal antibody for the treatment of primary immune thrombocytopenia (ITP), has achieved the primary endpoint of improvement in time to treatment failure in the phase 3 VAYHIT2 trial.

Announced on August 12 by parent company Novartis, ianalumab significantly extended the duration of safe platelet levels during and after treatment in patients with ITP previously treated with corticosteroids. These patients also saw a substantially higher rate of sustained improvements in platelet count, which was the central secondary endpoint of VAYHIT2.1

Investigators were encouraged by the drug’s potential for long-term disease maintenance, given the significant treatment burden that many alternative medications can accrue. Many patients require lifelong disease management to maintain optimal platelet counts, with management based primarily on immune suppression via corticosteroids and intravenous immunoglobulins.2

“While current treatments for ITP are generally effective in raising platelet counts, many patients require lifelong treatment to maintain safe levels, which can create a lasting treatment burden,” said Adam Cuker, MD, professor of medicine and chief, section of hematology, University of Pennsylvania. “The results from VAYHIT2 are encouraging, as they suggest that ianalumab may support longer periods of disease control and reduce the need for continuous treatment.”1

Ianalumab is a novel fully human monoclonal antibody currently in testing for the treatment of several B-cell-driven autoimmune diseases such as Sjogren’s disease, lupus nephritis, warm autoimmune hemolytic anemia, immune thrombocytopenia, and diffuse cutaneous systemic sclerosis. The drug targets B cells in 2 ways: by combining B cell depletion via antibody-dependent cellular toxicity and interruption of BAFF-R-mediated signals of B cell survival and function.1

The VAYHIT2 multicenter, randomized, double-blind trial saw patients treated with 2 different doses of ianalumab versus placebo, along with eltrombopag. Included patients had ITP, determined by a platelet count <30 G/L, who failed previous first-line treatment with corticosteroids. Patients were randomized in a 1:1:1 ratio to 4 monthly intravenous infusions of either ianalumab 3 mg/kg, ianalumab 9 mg/kg, or placebo.1

The primary endpoint of time to treatment failure was measured as time from randomization until either: a platelet count >30 G/L later than 8 weeks from randomization; the need for rescue therapy later than 8 weeks from randomization; initiation of a new ITP treatment at any time; inability or ineligibility to taper; or death. Secondary endpoints included measures of depth and duration of platelet response, patient-reported outcomes of quality of life and fatigue, and percentage of patients with a stable platelet count response at month 6, among others.1

“For many people living with ITP, chronic treatment can disrupt their daily life due to the burden of regular dosing, dose adjustments, and side effects,” said Shreeram Aradhye, MD, president, development and chief medical officer, Novartis. “These positive top-line results from the Phase 3 study highlight the potential of ianalumab, if approved, to deliver long-term disease control with 4 once-monthly doses and enable extended time off treatment.”1

Data from VAYHIT2 are expected to be presented at an upcoming medical meeting and will be included in regulatory submissions planned for 2027 in conjunction with results from the ongoing first-line ITP trial VAYHIT1. Ianalumab has already been granted Orphan Drug Designation by the US Food and Drug Administration and the European Medicines Agency.1

References

1. Novartis Pharma. Novartis ianalumab Phase III trial meets primary endpoint in ITP, demonstrating statistically significant improvement in time to treatment failure. GlobeNewswire. August 12, 2025. Accessed August 12, 2025. https://www.globenewswire.com/news-release/2025/08/12/3131405/0/en/Novartis-ianalumab-Phase-III-trial-meets-primary-endpoint-in-ITP-demonstrating-statistically-significant-improvement-in-time-to-treatment-failure.html

2. Mititelu A, Onisâi MC, Roșca A, Vlădăreanu AM. Current Understanding of Immune Thrombocytopenia: A Review of Pathogenesis and Treatment Options. Int J Mol Sci. 2024;25(4):2163. Published 2024 Feb 10. doi:10.3390/ijms25042163