Magnesium monitoring practice in monoclonal anti-epidermal growth factor receptor antibodies therapy

• Published in: Journal of clinical pharmacy and therapeutics Vol. 38; no. 2; pp. 101 - 103
• Main Authors: do Pazo-Oubiña, F., Estefanell-Tejero, A., Riu-Viladoms, G., Anglada-Martínez, H., Molas-Ferrer, G., Creus-Baró, N.
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.04.2013; Blackwell; Hindawi Limited
• Subjects: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal - administration & dosage; Antibodies, Monoclonal - adverse effects; Antibodies, Monoclonal, Humanized - administration & dosage; Antibodies, Monoclonal, Humanized - adverse effects; Biological and medical sciences; Cetuximab; Female; Humans; hypomagnesemia; magnesium; Magnesium - blood; Male; Medical sciences; Metabolic diseases; Metals (hemochromatosis...); Middle Aged; Other metabolic disorders; panitumumab; Pharmacology. Drug treatments; Receptor, Epidermal Growth Factor - antagonists & inhibitors; Receptor, Epidermal Growth Factor - immunology; Retrospective Studies; Antineoplastic agent; Hydroelectrolytic balance disorder; Anti-EGFR; Panitumumab; Monoclonal antibody; Inorganic element; Epidermal growth factor receptor; Immunomodulator; Metabolic disorder; Treatment; Surveillance; Magnesium; Cetuximab; Hypomagnesemia
• ISSN: 0269-4727; 1365-2710
• DOI: 10.1111/jcpt.12028

Summary What is known and Objective It is now estimated that about 5% of cetuximab‐treated patients and about 3% of panitumumab‐treated patients will develop grade 3–4 hypomagnesemia. The aim of this study was to assess the extent of magnesium monitoring in patients treated with epidermal growth factor receptor (EGFR)‐targeting antibodies and to estimate the incidence of hypomagnesemia in these patients at our institution. Methods A 2‐year retrospective study was carried out. At least four doses of weekly cetuximab or two doses of bi‐weekly panitumumab were required for inclusion. Serum magnesium profiles were reviewed from 1 month before treatment until 3 months after treatment discontinuation, and patients with <2 determinations were excluded. Results and Discussion Two hundred and one patients received at least one dose of EGFR‐targeting antibodies, but only 68 met the inclusion criteria. Seventy patients had <2 magnesium determinations. The overall hypomagnesemia was 58·82% (40 of 68 patients), with a 4·41% grade 3 hypomagnesemia (three of 68 patients). No grade 4 hypomagnesemia was detected. What is new and Conclusion There is a lack of magnesium monitoring in these patients. Serum magnesium determinations should be done every 4–8 weeks in patients treated with EGFR‐targeting antibodies, as it is a useful surrogate marker for both toxicity and efficacy.