The Billikens (10-2) had an early 11-point lead in the first half, but Indiana State countered with a 15-4 run to tie the game. Saint Louis closed on a 7-0 stretch capped off by a 3-pointer from Loe to grab a 34-27 halftime advantage.
Indiana State (7-3) was within five at the 12:40 mark in the second half, but Saint Louis surged away with a 21-10 run and led by 19 with 2:08 remaining.
Saint Louis, whose only defeats have come in narrow losses to ranked opponents Wisconsin and Wichita State, had an almost identical shooting percentage to the Sycamores, but made seven more 3-pointers. Austin McBroom had 15 points and Jordair Jett contributed 12 with seven assists.
Manny Arop led Indiana State with 16 points.
Maryland point guard Melo Trimble has withdrawn from the NBA draft and will return to College Park for his junior season.
Louisville's Chinanu Onuaku, who recently underwent a medical procedure to correct a heart rhythm issue detected during the combine, will keep his name in the NBA draft pool.
Andrew White III will return to the Nebraska men's basketball team next season after removing his name from the NBA draft.