Trastuzumab in Patients on Haemodialysis for Renal Failure

We report two cases of female patients with HER-2-positive metastatic breast cancer and coincidental end-stage renal failure on haemodialysis who received trastuzumab therapy. We are not aware of any previous published reports. Trastuzumab is a recombinant DNA derived, humanised mouse IgG kappa monoclonal antibody that selectively binds to the extracellular domain of HER-2/neu[ 1 Box B.A. Russell C.A. Breast cancer. in: Casciato D. Manual of clinical oncology. 5th edn. Lippincott Williams and Wilkins, 530 Walnut Street, Philadelphia, PA 19106, USA2004: 233-251 Google Scholar ]. Pharmacokinetics are non-linear and dose dependent. Elimination of the drug seems to involve clearance of IgG through the reticuloendothelial system and the half-life is estimated to be 28.5 days. To date there have been no data on the efficacy or safety of trastuzumab in breast cancer patients undergoing haemodialysis for renal failure. The summary of product characteristics does not recommend dosage adjustments in renal failure [ 2 http://www.rocheuk.com/ProductDB/Documents/rx/spc/Herceptin_SPC.pdf Google Scholar ] and Roche (UK) were unable to give any advice on administration in haemodialysis patients. Consultation with the consultant nephrologists suggested that significant removal of the drug during dialysis is unlikely due to the large molecular weight (about 150 000 Da) [ 3 Esteva F.J. Monoclonal antibodies, small molecules, and vaccines in the treatment of breast cancer. Oncologist. 2004; 9: 4-9 Crossref PubMed Scopus (62) Google Scholar , 4 Johnson CA, Simmons WD. Dialysis of drugs. 2006. Available from: http://www.nephrologypharmacy.com/downloads/DialysisDrugs2006.pdf. Google Scholar ]. We therefore proceeded to treat two patients and we report their cases here.