Janine Marciano recorded 26 points to help the Lady Red Spikers notch their third win in four outings.
Frances Molina backed up Marciano with 21 points, four on blocks.
San Beda, which improved to 3-1, kept their poise in the deciding fifth set as Letran, which remained winless at 4-0, fluttered.
Meanwhile, Emilio Aguinaldo College stretched its winning streak to three following a 25-15, 19-25, 25-22, 25-14 win over Arellano University.
Charmille Belleza registered 24 points while Arnie Yumul came through with 16 markers with four service aces.
Marciano’s 26-point performance was the third highest score next to Honey Rose Tubino’s 28 and Sandra delos Santos’ 27, both of the league-leading Perpetual Help Lady Altas.
Danna Henson paced Arellano, which dropped to 2-1, with 15 markers while Melissa Cu had 16 for Letran.