Risk of anti-EGFR monoclonal antibody-related hypomagnesemia: systematic review and pooled analysis of randomized studies.

INTRODUCTION: The typical class side effect of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (panitumumab and cetuximab) is a cutaneous maculopapular rash, although hypomagnesemia is also described to be a frequent adverse event. The purpose of our meta-analysis is to evaluate the frequency and the relative risk of hypomagnesemia in patients treated with cetuximab or panitumumab in randomized trials. AREA COVERED: Eligible studies included prospective randomized Phase III controlled trials in which cetuximab or panitumumab were compared with standard anti-neoplastic therapy or best supportive care. Summary incidence rates and relative risks with 95% confidence intervals were calculated. EXPERT OPINION: The overall incidence of hypomagnesemia was 17% among the patients who received the treatment, whose risk of developing hypomagnesemia turned out to be significantly increased compared with the patients treated with control medication, with an overall relative risk of 5.83 (p < 0.00001), where 3.87 refers to cetuximab and 12.55 to panitumumab. The addition of anti-EGFR monoclonal antibodies to standard anticancer therapy showed a significantly increased risk of hypomagnesemia compared with controls. The risk seems to be even higher for panitumumab, probably correlated with the increased risk of other adverse events (e.g., diarrhea and dehydration). Hypomagnesemia does not seem to be linked with any serious complications.