Magnesium sulphate in patients with thrombotic thrombocytopenic purpura (MAGMAT): a randomised, double-blind, superiority trial

• Published in: Intensive care medicine 2023-11, Vol.49 (11), p.1293-1304
• Main Authors: Zafrani, Lara, Canet, Emmanuel, Walter-Petrich, Anouk, Joly-Laffargue, Bérangère, Veyradier, Agnès, Faguer, Stanislas, Bigé, Naïke, Calvet, Laure, Mayaux, Julien, Grangé, Steven, Rafat, Cédric, Poulain, Coralie, Klouche, Kada, Perez, Pierre, Pène, Frédéric, Pichereau, Claire, Duceau, Baptiste, Mariotte, Eric, Chevret, Sylvie, Azoulay, Elie
• Format: Article
• Language: English
• Subjects: Adult; Analysis; Anesthesiology; Blood pressure; Care and treatment; Carfilzomib; Clinical trials; Critical Care Medicine; Death; Double-Blind Method; Double-blind studies; Emergency Medicine; Female; Health aspects; Humans; Intensive; Magnesium; Magnesium sulfate; Magnesium Sulfate - adverse effects; Male; Medicine; Medicine & Public Health; Original; Pain Medicine; Patients; Pediatrics; Pharmaceutical industry; Placebos; Platelet Count; Platelets; Pneumology/Respiratory System; Purpura; Purpura, Thrombotic Thrombocytopenic - drug therapy; Sulfates; Thrombocytopenia; Thrombocytopenic purpura; Thrombotic thrombocytopenic purpura; Treatment Outcome
• ISSN: 0342-4642; 1432-1238
• DOI: 10.1007/s00134-023-07178-6

Purpose Studies have suggested benefits from magnesium sulphate in thrombotic thrombocytopenic purpura (TTP). We aimed to measure the effects of magnesium sulphate supplementation on TTP recovery. Methods In this multicenter, randomised, double-blind, controlled, superiority study, we enrolled adults with a clinical diagnosis of TTP. Patients were randomly allocated to receive magnesium sulphate (6 g intravenously followed by a continuous infusion of 6 g/24 h for 3 days) or placebo, in addition to the standard treatment. The primary outcome was the median time to platelet normalisation (defined as a platelet count ≥ 150 G/L). Efficacy and safety were assessed by intention-to-treat. Results Overall, we enrolled 74 participants, including one who withdrew his/her consent. Seventy-three patients were further analyzed, 35 (48%) allocated to magnesium sulphate and 38 (52%) to placebo. The median time to platelet normalisation was 4 days (95% confidence interval [CI], 3–4) in the magnesium sulphate group and 4 days (95% CI 3–5) in the placebo group. The cause-specific hazard ratio of response was 0.93 (95% CI 0.58–1.48, p  = 0.75). The number of patients with ≥ 1 serious adverse reactions was similar in the two groups. By day 90, four patients in the magnesium sulphate group and two patients in the placebo group had died ( p  = 0.42) . The most frequent adverse event was low blood pressure occurring in 34% in the magnesium sulphate group and 29% in the placebo group ( p  = 0.80). Conclusion Among patients with TTP, the addition of magnesium sulphate to the standard of care did not result in a significant improvement in time to platelet normalisation.