Desensitization to Monoclonal Antibodies

Monoclonal antibodies (mAbs) represent a therapeutic option in patients with chronic inflammatory diseases and oncologic disorders. Desensitization is useful in cases of hypersensitivity reactions (HSRs) without a proper alternative. The aim was to evaluate the effectiveness and security of desensitization protocols in patients with HSR to mAbs. A retrospective-descriptive study was led at our Allergy Department. Medical records from January 2012-July 2014 were searched for HSRs to mAbs that underwent desensitization. Sixty-two desensitizations to mAbs were performed in 6 patients. Mean age 42.24 ±15.5, 50% women, 50% atopics. HSR was immediate in all cases (4 moderate, 2 severe). Two patients showed positive immediate intradermal-test (infliximab and rituximab). The prescribed mAbs were: cetuximab (28), infliximab (21), rituximab (10) and trastuzumab (3). Initially 4 patients had a 16-step and 2 a 12-step protocol. Four received pretreatment with AAS and/or montelukast based on the severity of the reaction. Sixty-one (98.4%) were successfully completed. Fourteen reactions were observed during 11 desensitizations in 4 patients: fever (6), pruritus/wheals(4), musculoskeletal pain (3), nauseas/vomits (3), and hypotension (1), 71.4 % were immediate, 78.6% mild. Only 2 required adrenalin. The initial protocol was modified in 4 patients to avoid new reactions. In all four, an extra and/or prolonged steps, had to be added. Three also received treatment during the following infusion, and in one, pretreatment was added (montelukast). There was no need to withdraw the biologic medication in none of the patients. Desensitization to mAbs is solidly effective and secure, although most protocols need to be personalized.