Need Help as Express Scripts has removed my IVIG from the prefered list

I was diagnosed with CIPD over 10 years ago and will be officially treating for 10 years this Dec. Now after all this time I have hit a bump in the road. United Health Care had to deny my treatment as apparently Express Scripts who handles the Pharmacy aspects of my health coverage has removed my IVIG from the preferred list.

I need need some help. Has anyone encountered this.

I know you have to appeal and I am working with my Neuro MD and Oncologist to get this done but they are not well versed in this as I am their only CIDP patient.

Can anyone give me any guidance, suggestions or even a copy of draft of an appeal letter to help me out.

Any help is greatly appreciated