The OGD posted 29 new and 31 revised product-specific guidances (PSGs) today (see here). The new list of PSGs covers drugs with various dosage forms including tablets, capsules, gels, oral suspensions, intramuscular extended-release suspensions, topical solutions, powders, ointments, other parenteral products and orally disintegrating tablets, and subcutaneous extended-release suspensions.

One of the new PGSs for memantine orally disintegrating tablets caught my eye as it had language in it that I had never seen before. It provided two study options, but both were fasting studies.

  • Option 1: One in-vivo bioequivalence study with pharmacokinetic endpoints using the designated RS for memantine hydrochloride tablets2
  • Option 2: One in-vivo bioequivalence study with pharmacokinetic endpoints using the designated RS for memantine hydrochloride ODT3

Note the new dosage form identified is the subject of an approved suitability petition (FDA-2007-P-0061).

And the footnotes are as follows:

  • 2 – The currently designated RS is the reference listed drug, NDA 021487, memantine hydrochloride tablets, 10 mg.
  • 3 – This option can be used when a petitioned ANDA for memantine hydrochloride ODT is approved and designated as the RS. There is currently no approved petitioned ANDA for memantine chloride ODT.

I presume that this is the OGD way of providing guidance for petitioned changes without an approved ANDA for the proposed ANDA suitability change.

The list of revised PSGs included a number that removed the requirement for a fed study as provided for in the M13A ICH guidance for low risk immediate-release solid oral dosage forms like the revised allopurinol PSG (here) and others that retained both the fasting and fed studies for certain immediate release solid oral dosage forms like phytonadione (here), which the agency must have concluded is a high-risk product, and simply announcing other changes to the previously issued PSG for phytonadione.

Yes, things are getting more complicated so continue to review the new and revised PSGs carefully, so your development program does not jump off track.