Lokko, an England C international who can operate both at centre-back and left-back, joined Stevenage from Maidstone United for an undisclosed fee last August.
He then joined Dagenham & Redbridge on loan, making twenty-five appearances, including one against Dover in November, before being recalled by his parent club in February.
His last appearance for Stevenage was last Saturday when he came on as a second half substitute in the 4-1 win against visiting Yeovil Town.
The 22-year-old former Norwich City, Colchester United and Welling United man played in forty-one National League games for Maidstone last season, scoring 4 goals in the process.
Lokko will be contention to make his debut at home to Dagenham tonight.