Depletion of neutralising antibodies resensitises a secondary non-responder to botulinum A neurotoxin
- aDepartment of Neurology, bDivision of Transfusion Medicine Immunohematology, Bayerische Julius-Maximilians-Universität, Würzburg, Germany, cDepartment of Pharmacology and Toxicology, Medizinische Hochschule Hannover, Hannover, Germany
- Dr Markus Naumann, Neurologische Klinik der Bayerischen Julius-Maximilians-Universität, Josef-Schneider-Straβe 11, 97080 Würzburg, Germany. Telephone 0049 931 201 2621; fax 0049 9367 980388.
- Received 4 March 1998
- Revised 12 May 1998
- Accepted 29 June 1998
Abstract
The objective was to evaluate whether removal of neutralising antibodies potentially resensitises a secondary non-responder to botulinum neurotoxin A (BoNT/A). Neutralising antibodies directed against BoNT/A are produced during long term treatment with BoNT/A-hemagglutinin complex in up to 10% of patients with cervical dystonia. These patients become secondary non-responders. Other serotypes of BoNT are not yet generally available and may also bear the risk of inducing antibody formation. Plasma exchange (PE) (one treatment cycle) and immunoadsorption on a protein A column (IA-PA; three treatment cycles) was employed over 15 months to remove neutralising antibodies from a severely disabled secondary non-responder with cervical dystonia. After plasma exchange or IA-PA, BoNT/A was reinjected. Antibodies were measured with a sensitive functional toxin neutralising test.
Repeated use of plasma exchange and IA-PA depleted neutralising antibodies to below the detection limit and subsequently allowed successful BoNT/A injection into dystonic muscles. No serious side effects were found related to the depletion of IgG.
In conclusion PE or IA-PA performed before BoNT/A readministration may provide an alternative strategy in treating selected secondary non-responders who are severely disabled.
