This guy's regen isn't so much the issue as the fact that he's a druid so he's got a DS and he loads you down with high end poison and disease DOTs. Don't forget also that everything but the defenders is a WIS caster, so he's probobly getting healed as well.
Fought him 8 times since he came out with those gloves - never dropped the gloves, dropped the blade once and the shield once - that was it.
He's a tough fight and this is one of those dungeons where even the greens jump into the fight - and god forbid someone causes one or more of those sporlings to pop.