Update on Ianalumab and Eltrombopag: Phase III Findings and Implications

The phase 3 VAYHIT2 trial showed that ianalumab plus eltrombopag meaningfully extended disease control in primary immune thrombocytopenia (ITP).

Median time to treatment failure increased by 45%, and median duration of control was 2.8-fold longer versus placebo plus eltrombopag. Clinically, this short-course biologic strategy—four once-monthly IV doses of ianalumab added to eltrombopag—delivers prolonged platelet stability for patients who have not responded to first-line corticosteroids.

VAYHIT2 randomized adults with primary ITP to ianalumab plus eltrombopag or placebo plus eltrombopag, using time to treatment failure and sustained platelet response as the co-primary efficacy measures and combining clinical and laboratory criteria to define endpoints. The active regimen produced the 45% extension in the principal endpoint, a 2.8-fold longer median control duration, and higher six‑month sustained platelet‑response rates—together indicating deeper and more durable control for second‑line ITP patients.

No new safety signals emerged. Adverse events were generally comparable across arms and consistent with prior ianalumab experience. Headache and infusion-related reactions were among the most frequent events; neutropenia occurred more often in treated patients but largely resolved without permanent discontinuation. Events did not lead to unexpected treatment-limiting toxicity, supporting consideration of this short-course B cell–targeted approach in eligible patients while maintaining routine monitoring for cytopenias and infusion reactions.