*Pericardial and Pleural Effusions after Evolocumab in a Patient with Severe Familial Hypercholesterolemia

Background/Synopsis

Inhibitors of PCSK9 by monoclonal antibodies (PSCK9mAb) are efficacious lipid lowering therapies with established outcome benefits. Side effects include nasopharyngitis, influenza-like illness, and injection site reactions.

Objective/Purpose

To describe a less-commonly reported adverse reaction to evolocumab in a patient with severe familial hyperlipidemia (FH), outline applicable testing, and treatment strategies.

Methods

We report a patient with severe FH who developed fever, elevated liver function tests (LFTs), pericardial and pleural effusions with evolocumab.

Results

A 70-year-old gentleman with hyperlipidemia presented to preventive cardiology clinic for consultation. His baseline LDL-cholesterol (LDL-C) was 400 mg/dL and examination revealed bilateral arcus senilis and xanthomas. Patient's paternal family members were all on lipid-lowering therapy although there were no early atherosclerotic events. Dutch criteria scoring was 21 (definite FH). His lifestyle was optimal, including a Mediterranean diet with daily walking. Risk assessment revealed a calcium score of 3000 AU, carotid atherosclerosis, and lipoprotein (a) of 233.1 nmol/L. Treatment with ezetimibe 10 mg oral daily and rosuvastatin 40 mg oral daily was initiated, achieving a post-treatment LDL-C of 130 mg/dL. To further improve the patient's outcomes by targeting a LDL-C of <70 mg/dL, evolocumab 140 mg subcutaneous biweekly was prescribed. After the first dose, he had fever. Two weeks after the second dose, he was hospitalized with: fever, elevated inflammatory markers and LFTs, pericardial and pleural effusions. Discontinuation resolved symptoms. Post-hospital discharge, laboratory abnormalities normalized. Colchicine and steroids were administered for pericarditis.

This case underscores complexities of managing lipid disorders when confronted with adverse reactions. Based on delayed-onset symptoms and laboratory abnormalities after medication, it is critically-important to consider the possibility of an immune-mediated reaction. The needle cover of the single-dose prefilled autoinjector of evolocumab contains a derivative of latex, a potential risk factor for triggering Gell-Coombs Type I and IV allergic reactions in latex-sensitive individuals. Percutaneous latex skin prick testing is pending. Evolocumab is fully humanized, reducing the risk of immunogenicity, yet this does not exclude adverse drug reactions. The mechanism for common adverse events associated with monoclonal antibodies involves a cytokine-mediated type alpha immune response, explaining flu-like symptoms and injection site reactions. Because of our patient's extensive atherosclerotic disease, additional evaluation will assist us in risk-stratifying treatment: alirocumab, inclisiran, evanicumab or lipoprotein apheresis to reach a target LDL-C of <70 mg/dL.

Conclusions

Delayed pleural and pericardial effusions after evolocumab in this patient with severe FH, supports the need for pre-treatment testing and discussion of alternatives. The severity of this uncommon response suggests a need for epidemiological studies.