Abstract Number: PB0830
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » Acquired Thrombocytopenias
Background: Efgartigimod, an FcRn antagonist, was well tolerated compared to placebo and induced a rapid reduction of total IgG levels, which was associated with clinically relevant increases in platelet counts, and a reduced proportion of patients with bleeding in the Phase 2 trial in patients with primary ITP (Newland AC. Am J Hematol. 2020;95:178-187. NCT03102593), warranting further evaluation in Phase 3 clinical trials. A subcutaneous (SC) formulation has been developed to offer additional flexibility and convenience for patients.
Aims: ADVANCE SC, a Phase 3, multicenter, randomized, double-blinded, placebo-controlled trial (NCT04687072), will evaluate the efficacy and safety of efgartigimod PH20 administered SC in adults with persistent or chronic ITP.
Methods: Eligible patients must have a mean platelet count <30×109/L over at least 3 qualifying evaluations and have received at least 2 prior ITP treatments or 1 prior and 1 concurrent treatment, with response to at least one. Patients will enter a 24-week treatment period and receive either efgartigimod (1,000 mg) co-formulated with PH20 or matching placebo (randomization 2:1), administered weekly from visits 1 to 4 and then either weekly or every other week from visits 5 to 16, as determined by platelet counts. Dosing schedule will be fixed from visits 17 to 24. Permitted concurrent ITP treatments include corticosteroids, oral immunosuppressants, dapsone/danazol, fostamatinib and/or oral TPO-RAs.
Results: The primary endpoint is the proportion of patients with a sustained platelet count response (≥50×109/L for at least 4 of the 6 visits between study weeks 19 and 24). Secondary endpoints include safety and tolerability, bleeding severity, quality of life and patient-reported outcome measures,
and the immunogenicity and pharmacokinetic/pharmacodynamic effects of efgartigimod.
Conclusions: Recruitment is ongoing in Asia-Pacific, Europe, Japan, Latin America, the Middle East, Africa and USA. Trial participants will be eligible for continuation into ADVANCE SC+, a long-term open-label extension trial.
To cite this abstract in AMA style:
Broome C, McDonald V, Jain S, Babu S, Oliva E, Parys W, Hultberg A, De Beuf K, Gandini D, Miyakawa Y, Ghanima W. Efficacy and Safety of Efgartigimod PH20 Subcutaneous in Adult Patients with Primary Immune Thrombocytopenia: ADVANCE SC, a Global Phase 3 Clinical Trial in Progress [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/efficacy-and-safety-of-efgartigimod-ph20-subcutaneous-in-adult-patients-with-primary-immune-thrombocytopenia-advance-sc-a-global-phase-3-clinical-trial-in-progress/. Accessed November 29, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/efficacy-and-safety-of-efgartigimod-ph20-subcutaneous-in-adult-patients-with-primary-immune-thrombocytopenia-advance-sc-a-global-phase-3-clinical-trial-in-progress/