Hello Berni
Sorry to hear of your Husbands fatigue after starting on Enzalutamide.
It is a common side effect.
I've been on Enzalutamide now for 6+ years.
Soon after I started it began to affect my stamina and I had to stop running in favour of hiking.
I've always taken the tabs early morning though and not tried last thing at night.
Maybe it will help.
Being outside walking helps me to minimise the fatigue but once I relax I'm worn out.
I hope this helps a bit.
Paul