Importance As new chemotherapy agents emerge, ophthalmologists may play a role in identifying vision-threatening adverse effects. Inherited retinal degenerations can offer insight into the changes that may result from pharmacologic inhibition of the signaling pathways involved in these conditions. Objective To present a case of a patient treated with a yes-associated protein (YAP)/transcriptional enhancer activator domain (TEAD) inhibitor who developed chorioretinal findings that resemble those seen in helicoid peripapillary chorioretinal degeneration (HPCD, also known as Sveinsson chorioretinal atrophy), an autosomal dominant disease caused by loss-of-function variants in TEAD1 . Design, Setting, and Participant Case report of a single patient at a large university hospital. Exposures The patient was treated with VT3989, a YAP/TEAD inhibitor, for 5 cycles. Main Outcomes and Measures Clinical evaluation and description of the ocular condition via fundus photography and fundus autofluorescence. Results A woman in her 50s with metastatic mesothelioma diagnosed several years previously presented for evaluation. Nine months before presentation, she had undergone several cycles of treatment with chemotherapy agent VT3989, which inhibits the interaction of the YAP and TEAD proteins that form the terminal transcriptional effector complex of the Hippo pathway, which is involved in control of cell fate, proliferation, apoptosis, and tissue regeneration. She developed visual decline associated with radially oriented areas of retinal pigment epithelium atrophy extending around both optic nerves, along with small scattered atrophic flecks elsewhere. Given the atypical nature of the peripapillary findings and the resemblance to a mild form of HPCD, which is caused by loss-of-function variants in TEAD1, these changes were presumed to be secondary to treatment with the YAP/TEAD inhibitor VT3989. Conclusions and Relevance Downregulation of the Hippo signaling pathway via YAP/TEAD inhibition in an adult patient may result in a phenotype resembling a mild form of HPCD (Sveinsson chorioretinal atrophy), underscoring the importance of this pathway in maintenance of the adult retina and retinal pigment epithelium. As novel cancer therapeutics continue to emerge, it may be important to ensure ophthalmologic monitoring of patients on drugs targeting the Hippo pathway.