From the Guidelines
Tocilizumab can cause several serious side effects, including increased risk of infections, gastrointestinal perforations, and liver damage, which can significantly impact morbidity, mortality, and quality of life. When considering the use of tocilizumab, it is essential to weigh the potential benefits against the risks of these side effects, particularly in patients with COVID-19 who may already be at increased risk of complications.
- Common side effects of tocilizumab include upper respiratory tract infections, headache, hypertension, elevated liver enzymes, and low white blood cell counts (neutropenia) 1.
- More serious side effects may include serious infections (such as tuberculosis, bacterial, fungal, or viral infections), gastrointestinal perforations, allergic reactions, and liver damage 1.
- Blood abnormalities like thrombocytopenia (low platelets) and neutropenia can occur, requiring regular blood monitoring during treatment 1.
- The use of tocilizumab in patients with COVID-19 has been associated with a reduced risk of mechanical ventilation and ICU admission, but the evidence is not yet conclusive, and the risk of side effects must be carefully considered 1.
- Patients should be screened for latent tuberculosis and other infections before starting tocilizumab, and vaccination status should be updated as live vaccines are not recommended during treatment 1.
- The most recent and highest quality study on the use of tocilizumab in COVID-19 patients, published in 2024, highlights the importance of careful patient selection and monitoring to minimize the risk of side effects 1.
From the FDA Drug Label
The most common adverse events (at least 5%) seen in ACTEMRA-IV treated patients in the 12 week controlled portion of the study were: upper respiratory tract infection, headache, nasopharyngitis and diarrhea Infections In the 12 week controlled phase, the rate of all infections in the ACTEMRA-IV group was 345 per 100 patient-years and 287 per 100 patient-years in the placebo group. The most commonly reported serious infections included pneumonia, gastroenteritis, varicella, and otitis media. Infusion related reactions were defined as all events occurring during or within 24 hours after an infusion. Anaphylaxis Anaphylaxis was reported in 1 out of 112 patients (less than 1%) treated with ACTEMRA-IV during the controlled and open label extension study Laboratory Abnormalities Neutropenia During routine monitoring in the 12 week controlled phase, a decrease in neutrophil below 1 × 109 per L occurred in 7% of patients in the ACTEMRA-IV group, and in no patients in the placebo group. Thrombocytopenia During routine monitoring in the 12 week controlled phase, 1% of patients in the ACTEMRA-IV group and 3% in the placebo group had a decrease in platelet count to no more than 100,000 per mm3 Elevated Liver Enzymes During routine laboratory monitoring in the 12 week controlled phase, elevation in ALT or AST at or above 3× ULN occurred in 5% and 3% of patients, respectively in the ACTEMRA-IV group and in 0% of placebo patients
The side effects of Tocilizumab include:
- Infections: such as upper respiratory tract infection, pneumonia, gastroenteritis, varicella, and otitis media
- Infusion related reactions: such as rash, urticaria, diarrhea, epigastric discomfort, arthralgia and headache
- Anaphylaxis: reported in less than 1% of patients
- Laboratory Abnormalities:
- Neutropenia: decrease in neutrophil below 1 × 109 per L occurred in 7% of patients
- Thrombocytopenia: decrease in platelet count to no more than 100,000 per mm3 occurred in 1% of patients
- Elevated Liver Enzymes: elevation in ALT or AST at or above 3× ULN occurred in 5% and 3% of patients, respectively 2
From the Research
Tocilizumab Side Effects
- The use of tocilizumab has been associated with several side effects, including:
- Late-onset infections, with bacterial pneumonia being the most common manifestation 3
- Elevated liver function tests (LFTs), observed in 51% of patients receiving tocilizumab 3
- Neutropenia, observed in 1.4% of patients receiving tocilizumab 3
- Hypertension, observed in 8% of patients receiving tocilizumab 3
- Gastrointestinal perforation, a rare but potentially life-threatening complication 4
- Opportunistic infections, such as Pneumocystis jirovecii and Aspergillus fumigatus, particularly in patients with rheumatoid arthritis 5
- Drug-induced liver injury, pancreatitis, and pulmonary fibrosis, identified as unpredictable adverse events through pharmacovigilance analysis 6
Serious Adverse Events
- A disproportionality analysis of the FDA Adverse Event Reporting System found statistically significant reporting odds ratios for 13 designated medical events, including:
- Drug-induced liver injury
- Pancreatitis
- Pulmonary fibrosis
- Hepatic reactions, with a median onset of 27.5 days and a proportion of deaths of 18.4% 6
Considerations for Use
- The potential for infections and tocilizumab-related toxicities should be carefully weighed when considering use, particularly in patients with rheumatoid arthritis or other immune-related conditions 3, 5
- Close monitoring is recommended for patients receiving tocilizumab, particularly for signs of liver injury, pancreatitis, and pulmonary fibrosis 6