Have your prescribing doctor look into "Intravenous immunoglobulin" (IVIg)
to find out if this would be an option.
I don't know if this is covered by OHIP, as it is a more expensive treatment
and not standard protocol. Also he has to evaluate your case, in regards to your present treatment and your reaction(s) to the prednisine and dosage.
By the way how severe is your PF and are you on generic prednisone?