You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Outcome", "Participant", "Intervention"].

Please return the output as a JSON object of the format: {"Participant" : ["patients with COPD", ...], "Intervention" : ["Atenolol", ...], "Outcome" : ["blood pressure", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Ranibizumab plus verteporfin photodynamic therapy in neovascular age-related macular degeneration : 12 months of retreatment and vision outcomes from a randomized study . PURPOSE To investigate the injection frequency and visual acuity ( VA ) outcomes with combination therapy ( ranibizumab plus verteporfin photodynamic therapy , PDT ) versus monotherapy ( ranibizumab ) . METHODS A total of 40 patients with exudative age-related macular degeneration were randomized 1:1 to ranibizumab 0.3 mg plus single standard verteporfin PDT or ranibizumab 0.3 mg plus sham PDT . Ranibizumab was administered 3 times monthly followed by 'as needed ' to month 12 based on predetermined vision/anatomical criteria . Retreatment rates , VA outcomes and safety were assessed . RESULTS During months 3-12 , combination therapy patients required fewer ranibizumab injections ( mean 1.3 ) compared with monotherapy patients ( 2.8 ) . Mean VA improved by 9.0 letters with combination therapy versus 7.5 letters in the monotherapy group at month 12 . Both treatment regimens were well tolerated . CONCLUSION The need for ranibizumab retreatment might be reduced by administering a single verteporfin PDT on the same day as the first ranibizumab injection , without compromising VA outcomes or safety .
{"Intervention": ["ranibizumab", "sham PDT", "ranibizumab plus verteporfin photodynamic therapy , PDT )", "Ranibizumab", "single standard verteporfin PDT", "verteporfin PDT", "verteporfin"], "Outcome": [], "Participant": ["exudative age-related macular degeneration were randomized", "40 patients"]}