Tecentriq® (atezolizumab): A new important identified risk of immune-related myositis

Roche Singapore Pte Ltd would like to inform healthcare professionals of the new safety concern of immune-related myositis associated with Tecentriq^® (atezolizumab). Dermatomyositis and polymyositis are amongst the most common types of myositis. Diagnosis is based on clinical (muscle weakness, muscle pain, skin rash in dermatomyositis), biochemical (serum creatine-kinase increase), and imaging (electromyography/magnetic resonance imaging) features, and is confirmed with a muscle biopsy.  Healthcare professionals are advised to withhold Tecentriq^® for moderate or severe (Grade 2 or 3) immune-related myositis and permanently discontinue the drug for recurrent severe or life-threatening myositis (recurrent Grade 3 and Grade 4). It is also recommended to administer corticosteroids and/or additional immunosuppressive agents for > Grade 2 events or if event does not improve after initial corticosteroids. Roche Singapore Pte Ltd is working with HSA to update the Singapore package insert for Tecentriq^® to include the risk of immune-related myositis. Please refer to the letter for details.