How to capture a located word in a line?

It is possible to tag the last word (Corinne) in a line before a tab?

Larrue Corinne (\t)              3: 6-38

     Luusa Mer Klaus (\t)      4: 9-18

in order to insert a period:

     Larrue, Corinne (\t)      3: 6-38

     Luusa Mer, Klaus (\t)      4: 9-18