Efficacy and safety of OK-432 immunotherapy of lymphatic malformations

Objectives: To determine the efficacy and safety of the immunostimulant OK‐432 (Picibanil) as a treatment option in the management of children with cervicofacial lymphatic malformations. Study Design: A prospective, randomized, multi‐institutional phase II clinical trial at 27 U.S. academic medical centers. Methods: 182 patients with lymphatic malformations (LM) were enrolled between January 1998 and November 2004. Of the 151 patients with complete case report forms, 117 patients were randomized into immediate or delayed treatment groups; 34 patients were nonrandomized and assigned to the open‐label group. Treatment consisted of a four‐dose intralesional injection series of OK‐432 at eight‐week intervals. Patients randomized into the delayed treatment group served as observational controls for spontaneous regression. Response to therapy was measured radiographically by quantitating change in lesion size and graded as complete (90%–100%), substantial (60%–89%), intermediate (20%–59%), or none (