Retinal Vasculopathy and Choroiditis after Pegcetacoplan Injection: Clinicopathologic Support for a Drug
Ankur Nahar1, Dean Eliott2, Robert L Avery3
1Department of Pathology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania.
Ophthalmology. Retina
|October 17, 2024
Summary
Severe vision loss after intravitreal pegcetacoplan injections may be caused by drug-induced, immune-mediated retinal vasculopathy and choroiditis (DIRVAC). Histopathology suggests a delayed hypersensitivity reaction as the mechanism of injury.
Area of Science:
- Ophthalmology
- Pathology
- Immunology
Background:
- Intravitreal pegcetacoplan is used to treat retinal diseases.
- Severe visual loss has been reported after pegcetacoplan administration.
Purpose of the Study:
- To detail the histopathology of eyes enucleated after intravitreal pegcetacoplan treatment.
- To propose the pathogenesis of hemorrhagic occlusive retinal vasculitis.
Main Methods:
- Retrospective, multicenter, clinical-pathologic analysis of 2 enucleated eyes.
- Histopathologic review and immunophenotypic characterization.
Main Results:
- Eyes showed vascular thrombosis, retinal hemorrhages, necrosis, and inflammation 9 days post-injection.
- Inflammatory infiltrate composed of T cells, macrophages, and eosinophils, primarily in the uvea.
- One eye had glomerular-like vascular proliferations and optic nerve vessel thrombosis.
Conclusions:
- Drug-induced, immune-mediated, retinal vasculopathy and choroiditis (DIRVAC) is a rare complication.
- Findings suggest a mixed-type, delayed hypersensitivity reaction as the mechanism of injury.
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