Bilateral Paracentral Corneal Melting and Left-Eye Perforation under Tobemstomig Novel Treatment

We present a rare occurrence of bilateral corneal melting and a left-eye corneal perforation in an oncologic patient undergoing a new biological therapy.

A 63-year-old male with a two-day history of a painful left red eye and bilateral visual impairment was enrolled in a multicenter phase-II study comparing tobemstomig/RO7247669, a PD1-LAG3 bispecific antibody, with nivolumab. Clinical examination revealed a bilateral central corneal thinning, and corneal OCT imaging indicated a significant stromal thinning of 124 μm in the right eye and a central corneal perforation of 286 μm in the left eye. Subsequently, the patient underwent surgical intervention involving an autologous partial scleral patch with a Gundersen conjunctival flap in the left eye, alongside a comprehensive topical and systemic treatment regimen. Due to this immune-related adverse event, the patient was excluded from the clinical trial subsequently later revealing he had been on the bispecific treatment.

While immune checkpoint inhibitors hold promise in oncology, they can lead to ocular surface issues, including dry-eye keratitis and, in severe cases, anterior segment thinning culminating in corneal perforation. Timely withdrawal of immunotherapy, coupled with multi-level treatment involving anti-inflammatory and corneal healing approaches, is crucial. In cases of corneal perforation, surgical intervention such as cyanoacrylate application or tectonic surgery becomes imperative.