Oral magnesium supplements for cancer treatment‐induced hypomagnesemia: Results from a pilot randomized trial

Abstract

Background and Aims Optimal management of cancer treatment‐induced hypomagnesemia (hMg) is not known. We assessed the feasibility of using a novel pragmatic clinical trials model to compare two commonly used oral Mg replacement strategies. Methods Patients with grade 1 to 3 hMg while receiving either platinum‐based chemotherapy or epidermal growth factor receptor inhibitors (EGFRI) were randomized to oral magnesium oxide (MgOx) or oral magnesium citrate (MgCit). The trial methodology utilized the integrated consent model. Feasibility would be successful if; accrual rate was ≥5 patients a month and if measures of patient and physician engagement, were > 50%. Secondary endpoints included; comparison of Mg levels, cardiac arrhythmias, and rates of treatment delay/hospitalizations. Results From July 2016 to December 2017, an average of 1 patient a month was accrued. All 15 eligible and approached patients consented to participate in the study (100% engagement) and 7/15 were randomized to MgOx and 8/15 to MgCit. The percentage of physicians who approached patients for the study was 4 of 6 (66.6% engagement). The mean slope of change in Mg (mmol/L/day) was 0.0022 (95% CI: −0.0001 to 0.0044) for MgOx and 0.0006 (95% CI, −0.0012 to 0.0024) for MgCit (P = .2123). Three patients (20%) required IV magnesium while on the study (2 MgCit and 1 MgOx). Grade 1 diarrhea occurred in 3 patients in the MgCit arm. Conclusion Despite oral magnesium tolerability and meeting most of its feasibility endpoints, this study did not meet its target accrual rate. Alternative designs would be necessary for a definitive efficacy study.

Recommendations for Nutritional Supplementation in Pediatric Oncology: A Compilation of the Facts

“…In the case of cisplatin, magnesium losses can be severe and persist despite discontinuation of therapy. In adult patients, the incidence of cisplatin-induced hypomagnesemia is reported to be as high as 90% [ 69 ]. Sustained excretion rates also apply for amphotericin B; other nephrotoxic agents include loop and thiazide diuretics, aminoglycosides, and cyclosporine [ 70 , 71 , 72 , 73 ].…”

“…Thus, low levels of serum Mg do not always correlate with the development of symptoms, which further depends on the severity of Mg deficiency and the rate of its decline. Consequently, Mg replacement can be challenging, with oral replacement strategies generally being more effective at slowly replacing body stores but intravenous replacement being more effective at treating severe cases of hypomagnesemia [ 66 , 69 , 74 ].…”

Risk Factors of Cetuximab-Induced Hypomagnesemia and the Effect of Magnesium Prophylaxis in Patients with Head and Neck Cancer: A Retrospective Study

“…However, these methods have proven inconsistent and intolerable due to associated diarrhea, which can lead to further Mg loss. [8][9][10] Considering these factors, our institute has implemented prophylactic intravenous Mg sulfate administration as a clinical practice for several years.…”