{"id":"0f673b86-90b6-5490-b101-fe2fc49e8dfa","stable_key":"8ccb5461-efe2-5d95-9869-950d7cd50575:tadalafil-pde6-selectivity-versus-sildenafil","predicate":"inhibits_less_than_sildenafil_does","statement":"Tadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"34aa7eda-5567-5d08-ac79-8a6b8befd28c","mechanism_event_label":"Tadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.","subject":{"id":"9820ebfe-515d-50cc-9b44-2bd2be220325","slug":"tadalafil","display_name":"Tadalafil","entity_type_key":"drug"},"object":{"id":"3a7633ec-a265-5827-988d-eed442633b39","slug":"pde6-family","display_name":"Phosphodiesterase 6 family","entity_type_key":"protein_family"},"evidence_count":1,"mechanism_event":{"id":"34aa7eda-5567-5d08-ac79-8a6b8befd28c","stable_key":"8ccb5461-efe2-5d95-9869-950d7cd50575:tadalafil-pde6-selectivity-versus-sildenafil-event","event_type":"observed_relationship","label":"Tadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.","description":"Tadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9820ebfe-515d-50cc-9b44-2bd2be220325","slug":"tadalafil","display_name":"Tadalafil","entity_type_key":"drug"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"3a7633ec-a265-5827-988d-eed442633b39","slug":"pde6-family","display_name":"Phosphodiesterase 6 family","entity_type_key":"protein_family"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"fe62cf8d-5f89-5e19-bc36-03ad3c9063b7","slug":"sildenafil","display_name":"Sildenafil","entity_type_key":"drug"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"0be8b435-6b8a-592c-bd4c-c0efd9481a97","slug":"pde5-family","display_name":"Phosphodiesterase 5 family","entity_type_key":"protein_family"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"duration","value_text":"Not applicable","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_access","value_text":"Primary PubMed abstract and indexed metadata reviewed. Full-text method details not stated here remain unresolved.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Isolated phosphodiesterase enzyme assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Tadalafil compared with sildenafil","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"A ratio measured in enzyme assays; PDE6 is the retinal phototransduction phosphodiesterase, and this comparison does not by itself establish a difference in visual effects in people.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"Isolated phosphodiesterase enzyme assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Tadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"The discovery of tadalafil: a novel and highly selective PDE5 inhibitor. 2. (2003). https://pubmed.ncbi.nlm.nih.gov/14521415/ DOI: 10.1021/jm0300577","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"route","value_text":"In vitro","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue","value_text":"Selectivity ratio between PDE5 and PDE6","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"af013db0-f704-5f49-a416-2135a5cb72d2","evidence_kind":"source_excerpt","locator":"Lines 24-33","start_line":24,"end_line":33,"excerpt":"## tadalafil-pde6-selectivity-versus-sildenafil\nTadalafil showed 85-fold greater selectivity against PDE6 than sildenafil.\nModel/species: Isolated phosphodiesterase enzyme assays\nTissue/system: Selectivity ratio between PDE5 and PDE6\nExposure: Tadalafil compared with sildenafil\nRoute: In vitro\nDuration: Not applicable\nLimits: A ratio measured in enzyme assays; PDE6 is the retinal phototransduction phosphodiesterase, and this comparison does not by itself establish a difference in visual effects in people.\nPrimary reference: The discovery of tadalafil: a novel and highly selective PDE5 inhibitor. 2. (2003). https://pubmed.ncbi.nlm.nih.gov/14521415/ DOI: 10.1021/jm0300577\nAccess: Primary PubMed abstract and indexed metadata reviewed. Full-text method details not stated here remain unresolved.","model_system":"","directness":"reported_statement","verification_status":"source_derived_draft","notes":"","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"cca24ae7-e036-525c-a440-4cc2e38ccb4d","stable_key":"import-8ccb5461-efe2-5d95-9869-950d7cd50575","title":"Tadalafil: PDE5 occupancy, the cGMP route and three measured endpoints (2026-09-22)","document_type":"imported_text","citation_label":"Original AI-assisted curation of seven primary studies resolved by PubMed title search, with every abstract read and all DOIs cross-checked against live PubMed metadata. Two references carry an unresolvable erratum and are recorded as corrected. Study-specific doses, effect sizes and limitations retained. Not publisher full text.","file_path":"","sha256":"3df8ec8f7114f983e8cae9fbc54912d3ac5b5f962454afea9dd8d4438c94cded","revision_id":"510acdea-65ae-57a6-b743-68e031ff1f05","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}