Longtime Xolair patient here: as far as cost goes, there are copay programs that knock the price down to $5/mo, but the catch is that you have to be insured (via commercial health insurance, not Medicare/Medicaid) to qualify.

A lot of drug manufacturers offer these programs: the bargain is essentially that they'll cover the brunt of your copay cost so long as your insurance company is still paying for the rest of it. Better to collect a few grand from the insurance company and reimburse the patient for a few hundred than to miss out on the sale entirely.