No spa at present but there are local vendors that offer the service
The Wilshire Grand has an exercise gym open 24 hours with Treadmills, Stationary Bikes, and Yoga classes.
I haven't used them but my grown athletic sons did and found them useful in maintaining their daily workouts.
i don't think they offer massages or other treatments found in a health spa, but those services are available down the road at spas nearby.
Get an answer from The Wilshire Grand Hotel staff and past guests.