I am not a bonafide expert in this arena. Conceptually, an Orphan Drug status will help expedite the FDA approval review/approval process. In summary, the FDA has targeted Orphan drug disease areas as those where drugs are very much needed....as apparently there are not adequate drugs and/or therapies to treat these types of diseases.
So by targeting these unmet need; the path to commercialization should be expedited (as the FDA will and should be more willing to approve (consider worthy drugs to address this types of diseases).
3) A description of the rare disease or condition for which the drug is being or will be investigated, the proposed indication or indications for use of the drug, and the reasons why such therapy is needed.
(4) A description of the drug and a discussion of the scientific rationale for the use of the drug for the rare disease or condition, including all data from nonclinical laboratory studies, clinical investigations, and other relevant data that are available to the sponsor, whether positive, negative, or inconclusive. Copies of pertinent unpublished and published papers are also required.
Also AMBS delivery method for MANF also depends on the Indication it will target, if its in the Eye or Ear it will be easier to deliver there than into the brain IMO .. I am no expert either correct me if I'm wrong, but I also remember in the past AMBS was involved with a company that delivered therapeutics via a patented inhaling device..