View only fillable fields for Adobe Sign

Hello. I have templated PDF that has fillable fields. We fill out the fields and then send it off for signature to people. When I send it via Adobe Sign, the fillable fields (that I filled out) are editable for the receiver. We need those fillable items to be view only when we send it for signature. Is this possible? How can I send a PDF with fillable fields out for signature and only allow the receiver to sign the document?