The purpose of this study is to evaluate the effect of two different doses of ianalumab added to eltrombopag to prolong Time to Treatment Failure (TTF) in adults with primary ITP who failed previous first-line treatment with steroids.

This is a multicenter, randomized, double-blinded phase 3 study to assess efficacy and safety of two different doses of ianalumab versus placebo in addition to eltrombopag in adults with primary ITP (platelet count <30 G/L) who failed previous first-line treatment with corticosteroids.

After completion of the screening period, the participants will enter the randomized treatment period (ianalumab/placebo with eltrombopag) followed by the eltrombopag tapering period. Afterwards, all participants will enter the follow-up period to be monitored for efficacy and safety or safety only depending on how the participants responded to the study treatment.

Key Inclusion criteria

1. Male or female patients aged 18 years and older on the day of signing the informed consent.
2. A signed informed consent must be obtained prior to participation in the study.
3. A diagnosis of primary ITP, with insufficient response to, or relapse after a first-line corticosteroid therapy ± IVIG.
4. Patient with platelet count <30G/L (whom eltrombopag is clinically indicated as per physician's discretion) and with no contraindication to receive eltrombopag

Key Exclusion criteria

1. ITP patients who received second-line ITP treatments (other than steroid therapy± IVIG) including splenectomy. However, patients exposed to thrombopoietin receptor agonists (TPO-RAs) for a limited time (max one week) before screening are eligible.
2. Patients with key lab abnormalities and patients with Evans syndrome or any other cytopenia, (patients with low grade anemia related to bleeding or iron deficiency are eligible).
3. Patients with history of clinically significant hematological disorders, or with marked altered hematologic parameters
4. Patients with current or history of life-threatening bleeding
5. Patient that are Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), Hepatitis B surface Antigen (HBsAg)/ Hepatitis B core antibody (HBcAb)-positive. HBcAb-positive patients can be enrolled if HBsAg negative, HBV DNA negative, no pre-existing liver fibrosis is present and antiviral prophylaxis is given
6. Patients with known active or uncontrolled infection requiring systemic treatment during screening period
7. Patients with hepatic impairment
8. Patients with concurrent coagulation disorders and/or receiving antiplatelet or anticoagulant medication with an exemption of low dose of acetylsalicylic acid (≤150 mg daily)
9. Nursing (breast feeding) or pregnant women

Other protocol-defined inclusion/exclusion criteria may apply.

Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations.

This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com