Edictum Perpetuum
Eventually, the above discretion allowed the Praetor urbanus regarding his Edict was no longer considered appropriate. Accordingly circa AD 129, action was taken that severely restricted its further modification. Under the emperor Hadrian (r. 117–138), the celebrated jurist Salvius Julianus made a formal revision to the Praetor's Edict as well as to similar edicts, e.g., that of the Aediles. This newly edited and consolidated version of the edict then became fixed, subject only to changes approved by the Emperor: hence, the Edictum perpetuum.
Read more about this topic: Praetor's Edict