EP3759113A1 - 10-(DI(PHENYL)METHYL)-4-HYDROXY-8,9,9A,10-TETRAHYDRO-7H-PYRROLO[1 ',2':4,5]PYRAZINO[1,2-B]PYRIDAZINE-3,5-DIONE DERIVATIVES AND RELATED COMPOUNDS AS INHIBITORS OF THE ORTHOMYXOVIRUS REPLICATION FOR TREATING INFLUENZA