The out-half has increased his training load with Leinster, having not played since April.
Sexton sustained his latest head injury during the Heineken Champions Cup quarter-final win over Exeter.
This weekend’s Rainbow Cup meeting with Glasgow is likely to come too soon for a full return.
Meanwhile, Donadea's Will Connors will miss the remainder of the season having undergone knee surgery.

Andy Farrell Names Ireland Team For Saturday's Six Nations Clash With Scotland
Thursday Morning Sports Update
Jockey Paul Townend Achieves 40th Cheltenham Win In Today's Opening Race
Ireland's Inaugural Nations Championship Home Fixtures Confirmed
Wednesday Morning Sports Update
Lossiemouth Has Won The Champion Hurdle On The Opening Day Of The Cheltenham Festival
Niall Scannell Will Retire From Munster Rugby At The End Of The Season
Old Park Star has won the Supreme Novices' Hurdle