There are a number of ways to skin that cat.
In case of P and N FET design it may be possible to use high voltage BJT? to drive the upper half of the bridge.
In case of N channel FET upper half there are a few ways to drive the gate source junction.
The bot strap charge pump driver, a small low power isolated DC to DC converter in conjunction with an opto coupler for high speed operation limited by opto coupler performance.
A similar approach using a photo voltaic coupler good for low speed gate drive. Drive capability affected by gate source capacitance. ( see Panasonic's APV2111VY for example)
