A phase 2 prospective study of bortezomib, cyclophosphamide, and dexamethasone in patients with newly diagnosed iMCD

TO THE EDITOR:

Human herpesvirus 8 (HHV-8)–negative idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disorder.¹ Patients with iMCD experience a wide spectrum of life-threatening cytokine storm–related symptoms including fatigue, fever, anorexia, weight loss, and ascites.² A subset of patients with iMCD have shared manifestations, including thrombocytopenia, anasarca/ascites, reticulin fibrosis in bone marrow, renal dysfunction, and organomegaly (TAFRO) and are identified as having the iMCD-TAFRO clinical subtype.³ Patients with iMCD not meeting the criteria for iMCD-TAFRO are considered to have iMCD-not otherwise specified (iMCD-NOS).

Interleukin-6 (IL-6) is known to play a key role in a portion of patients. Siltuximab, as an IL-6–directed monoclonal antibody, induced a complete or partial response rate of 34% in an international randomized controlled trial and showed a significantly improved progression-free survival (median, 14.5 months) compared with the placebo group.^4,5...