Low dose vs high dose tocilizumab in COVID-19 patients with hypoxemic respiratory failure.

PURPOSE: Tocilizumab has been shown to decrease mortality when used concomitantly with steroids in COVID-19 with 8 mg/kg (max 800 mg) being the standard dose. Our study sought to assess whether a low dose (400 mg) shows similar benefit compared to a high dose for COVID patients concurrently on the same median dose of steroids. MATERIALS/METHODS: A retrospective, multihospital observational study of COVID-19 patients who received tocilizumab in conjunction with steroids between March 2020 and August 2021 was conducted. RESULTS: A total of 407 patients were analyzed with low dose group being significantly more ill at baseline as a higher percentage of patients received vasopressors, were admitted to the ICU and on mechanical ventilation. In the propensity-matched analysis, both groups receiving a median dexamethasone equivalent dose of 10 mg showed no difference in 28-day mortality (p = 0.613). The high dose group had a higher rate of fungal and viral infections. CONCLUSION: Compared to low dose tocilizumab, the high dose did not provide additional efficacy and mortality benefit but resulted in higher fungal and viral infections. This study illustrates that low dose tocilizumab can be an alternative to high dose during a drug shortage of tocilizumab without compensating for efficacy and safety, conserving resources for more patients.

6-Mercaptopurine and Macrophage Activation Syndrome Case Report and Review of the Literature.

Macrophage activation syndrome is a life-threatening syndrome of uncontrolled immune activation with variable clinical presentation making early diagnosis difficult. It is often manifested by the development of multi-organ failure due to systemic inflammatory response. Patients with ulcerative colitis (UC) on purine antimetabolites are at high risk for severe myelosuppression due to the mechanism of thiopurine toxicity which potentially contributes to the development of macrophage activation syndrome. We present a case of a 39-year-old woman with a 2-year history of UC previously treated with 6-mercaptopurine (6-MP) and recent COVID-19 infection, who was admitted to our emergency department for C. difficile infection and subsequently developed macrophage activation syndrome. This case report also raises the question of whether abrupt discontinuation of 6-MP may have contributed to the worsening of the patient's symptoms of underlying hemophagocytic lymphohistiocytosis (HLH) and her rapid deterioration. Both macrophage activation syndrome and COVID-19 infection can produce a large number of pro-inflammatory cytokines termed "cytokine storm," but a pro-inflammatory cytokine panel breakdown helps to differentiate between the two. Our case report emphasizes the importance of close monitoring of patients on purine antimetabolite therapy who present with signs and symptoms of systemic toxicity.

Low-Dose Tocilizumab With High-Dose Corticosteroids in Patients Hospitalized for COVID-19 Hypoxic Respiratory Failure Improves Mortality Without Increased Infection Risk.

BACKGROUND: Severe hypoxic respiratory failure from COVID-19 pneumonia carries a high mortality risk. There is uncertainty surrounding which patients benefit from corticosteroids in combination with tocilizumab and the dosage and timing of these agents. The balance of controlling inflammation without increasing the risk of secondary infection is difficult. At present, dexamethasone 6 mg is the standard of care in COVID-19 hypoxia; whether this is the ideal choice of steroid or dosage remains to be proven. OBJECTIVES: The primary objective was to assess the impact on mortality of tocilizumab only, corticosteroids only, and combination therapy in patients with COVID-19 respiratory failure. METHODS: A multihospital, retrospective study of adult patients with severe respiratory failure from COVID-19 who received supportive therapy, corticosteroids, tocilizumab, or combination therapy were assessed for 28-day mortality, biomarker improvement, and relative risk of infection. Propensity-matched analysis was performed between corticosteroid alone and combination therapies to further assess mortality benefit. RESULTS: The steroid-only, tocilizumab-only, and combination groups showed hazard reduction in mortality at 28 days when compared with supportive therapy. In a propensity-matched analysis, the combination group (daily equivalent dexamethasone 10 mg and tocilizumab 400 mg) had an improved 28-day mortality compared with the steroid-only group (daily equivalent dexamethasone 10 mg; hazard ratio (95% CI) = 0.56 (0.38-0.84), P = 0.005] without increasing the risk of infection. CONCLUSION AND RELEVANCE: Combination of tocilizumab and corticosteroids was associated with improved 28-day survival when compared with corticosteroids alone. Modification of steroid dosing strategy as well as steroid type may further optimize therapeutic effect of the COVID-19 treatment.