How would you approach treating patients with biopsy-proven Hailey-Hailey disease refractory to multiple oral therapies (i.e. tetracyclines, naltrexone, apremilast, glycopyrrolate, Cellcept), and requiring monthly steroid tapers for disease flares?   

I find Hailey-Hailey so challenging and so I often do throw the kitchen sink. Additional options behind what you mentioned include low-dose superficial XRT (recently reviewed in JAMA Dermatology), botulinum toxin, dupilumab, and oral jak inhibitors. My personal approach to those who respond to predn...

I personally have used botulinum toxin with excellent results. 

Botulinum toxin would be my next choice.

My most severe Hailey-Hailey patient is now 95% clear on the following regimen: IM Kenalog 40 mg q 3 months. Topical Zoryve (roflumilast) daily. (Note: she had failed all of the above, plus CO2 laser.)

Weight loss, Botox...perhaps oral Robinul.