Successful Spell Resistance

Pathfinder Core Rulebook, page 565

Spell resistance prevents a spell or a spell-like ability from affecting or harming the resistant creature, but it never removes a magical effect from another creature or negates a spell’s effect on another creature. Spell resistance prevents a spell from disrupting another spell.

Against an ongoing spell that has already been cast, a failed check against spell resistance allows the resistant creature to ignore any effect the spell might have. The magic continues to affect others normally.