PROLONGED SURVIVAL ASSOCIATED WITH IMMUNE-RESPONSE IN A PATIENT TREATED WITH LYM-1 MOUSE MONOCLONAL-ANTIBODY

A patient with aggressive, chemotherapy-resistant non-Hodgkins lymphom a (NHL) was treated with I-131-Lym-1, a mouse antibody, on a protocol designed for serial therapy. Human anti-mouse antibody (HAMA) develope d within 1 month of initial therapy. The patient also developed an ant ibody to the hypervariable region of the Lym-1 antibody (Lym-1 specifi c). Because the patient was responding to therapy, plasmaphoresis was used to reduce the level of HAMA followed by unlabeled Lym-1 calculate d to be sufficient to block residual HAMA. This allowed additional the rapy on three subsequent occasions over 5 months. Despite very high HA MA levels, no untoward effects from administrations of Lym-1 were obse rved. The HAMA response of the patient included anti-Lym-1 specific an tibodies containing anti-idiotypic antibodies. The anti-Lym-1 antibody level has been sustained over the 9 year interval since I-131-Lym-1 t herapy and has been associated with a uniquely long remission of the p atient's disease. These observations demonstrate that, under certain c ircumstances, radioimmunotherapy (RIT) can be given safely and effecti vely despite HAMA. Anti-idiotypic antibodies could have induced an imm une cascade that contributed to the prolonged disease-free survival of the patient.