In Reply We read with interest the letter from Sun et al regarding possible pathophysiologic implications of our article on birdshot-like chorioretinopathy associated with pembrolizumab treatment.1 In the article, we observed a single patient who was treated for cutaneous melanoma with a checkpoint-inhibitor agent directed against the programmed cell death-1 receptor on T cells and soon thereafter developed a classic-appearing case of birdshot chorioretinopathy (BCR) in both eyes. Testing for HLA-A29 was negative. We speculated that this immunotherapy was associated with the development of clinical features of BCR.