Can adalimumab (tumor necrosis factor-alpha inhibitor) cause thrombosis?

From the Guidelines

Adalimumab, a tumor necrosis factor-alpha (TNF-α) inhibitor, has not been clearly established as a direct cause of thrombosis. Current evidence does not support a strong association between adalimumab and increased risk of blood clots. In fact, by reducing inflammation, TNF-α inhibitors like adalimumab may theoretically decrease thrombotic risk in some patients with inflammatory conditions, as chronic inflammation itself is a known risk factor for thrombosis.

Key Points to Consider

• The provided evidence 1 does not directly link adalimumab to an increased risk of thrombosis.
• Patients taking adalimumab should be aware that the underlying inflammatory conditions it treats (such as rheumatoid arthritis, inflammatory bowel disease, or psoriasis) are independently associated with increased thrombosis risk.
• When prescribing adalimumab, clinicians typically do not need to add additional thromboprophylaxis specifically due to the medication itself.
• Patients with pre-existing thrombotic risk factors should continue their usual preventive measures.
• The biological mechanism behind this relates to TNF-α's complex role in coagulation - while it can promote coagulation in some contexts, its inhibition does not appear to significantly disrupt normal clotting balance in most patients.

Clinical Implications

• The management of patients on adalimumab should focus on the underlying condition being treated and its associated risks rather than the medication itself causing thrombosis.
• Regular monitoring for signs of thrombosis and adjusting treatment according to individual patient risk factors is crucial.
• The use of anticoagulants or antiplatelet agents should be based on the patient's overall risk profile and not solely on the use of adalimumab.
• Clinicians should be aware of the potential for drug interactions, especially with medications that affect coagulation or increase the risk of thrombosis. Given the most recent and highest quality evidence available, adalimumab is not considered a direct cause of thrombosis, and its use should be weighed against the benefits of treating the underlying inflammatory condition, considering the patient's individual risk factors for thrombosis 1.

From the FDA Drug Label

Vascular disorders: Systemic vasculitis, deep vein thrombosis

Adalimumab can cause thrombosis, specifically deep vein thrombosis, as reported in the postmarketing experience section of the drug label 2.

From the Research

Adalimumab and Thrombosis

• Adalimumab, a tumor necrosis factor-alpha inhibitor, has been associated with various side effects, including rare serious infections and cytopenias 3.
• There is evidence to suggest that adalimumab may cause thrombocytopenia, a condition characterized by low platelet count, which can increase the risk of thrombosis 4.
• A case study reported a patient who developed severe thrombocytopenia after receiving adalimumab, which was resolved after discontinuation of the treatment 4.
• Another study reported a case of adalimumab-induced thrombocytopaenic microangiopathy, a condition characterized by thrombocytopenia and microangiopathic hemolytic anemia 5.
• However, it is worth noting that the majority of studies on adalimumab have focused on its efficacy and safety in treating Crohn's disease, rheumatoid arthritis, and other conditions, with limited information on its potential to cause thrombosis directly 6, 7.

Mechanisms and Risks

• The exact mechanisms by which adalimumab may contribute to thrombosis are not fully understood, but it is thought to involve the inhibition of tumor necrosis factor-alpha, which can lead to changes in platelet function and coagulation pathways 4, 5.
• The risk of thrombosis associated with adalimumab may be increased in patients with underlying conditions, such as cardiovascular disease or hypercoagulable states 3.
• Monitoring of platelet counts and other coagulation parameters may be necessary in patients receiving adalimumab, particularly those with a history of thrombocytopenia or other bleeding disorders 4, 5.

Clinical Implications

• Clinicians should be aware of the potential risks of thrombosis associated with adalimumab and monitor patients closely for signs and symptoms of thrombocytopenia or other coagulation disorders 3, 4, 5.
• Further studies are needed to fully understand the relationship between adalimumab and thrombosis, as well as to develop strategies for mitigating these risks in patients receiving this treatment 6, 7.