Ann: FDA Guidance on NUZ-001 IND Application, page-67

So we gave the FDA all the data that we had available, and there was no problem with any of our Monepantel data.

It was historical data that Elanco has, and that is likely to be well before dogs, and well before Pharmaust started dealing with Elanco.

"to assess the adequacy of systemic exposure" means it was a toxicology study.
https://www.ema.europa.eu/en/documents/scientific-guideline/ich-s-3-toxicokinetics-guidance-assessing-systemic-exposure-toxicology-studies-step-5_en.pdf

So, one of the 50 studies cited in the IND, and take your pick of which one.
Here's a sample from 2006/08:
from the Import Tolerance Environmental Assessment that is on file with the FDA:
9. References

• Jung M, McLellan G, Karadzovska D, Strehlau G (2007) ADME and residue depletion study of [14C]AHC 2102225 in sheep. Unpublished report from Elanco, Elanco Centre de Recherché Santé Animale, Switzerland. Study Report No. CRA 05/151.
• Karadzovska D (2007a) Residues of AHC-2102225 in edible tissues of Suffolk sheep following a single oral dose of AHC-2102225 at 3.75 mg/kg. Unpublished report from Elanco Animal Health Australasia Pty. Ltd. Study Y07/21, Report Y07/21/2154.
• Karadzovska D (2007b) Residues of AHC-2102225 in edible tissues of cross-bred fattening lambs following a single oral dose of AHC-2102225 at 3.75 mg/kg. Unpublished report from Elanco Animal Health Australasia Pty. Ltd. Study Y07/17, Report Y07/17/2157.
• Karadzovska D (2007c) Residues of AHC-2102225 in edible tissues of Merino sheep following a single oral dose of AHC-2102225 at 3.75 mg/kg. Unpublished report from Elanco Animal Health Australasia Pty. Ltd. Study Y07/16, Report Y07/16/2158.
• Karadzovska D (2007d) Determination of pharmacokinetic parameters of AHC-2102225 and AHC-2144670 in sheep following IV and oral administration of AHC-2102225 and IV administration of AHC-2144670. Unpublished report from Elanco Animal Health Australasia Pty. Ltd. Study Y06/72, Report Y06/72/2159.
• Meinerling M (2007) Determination of the adsorption / desorption behavior of AHC2102225. Unpublished report from IIBACON, Rossdorf, Germany, Study Report No. 24877195, 11. Oct. Sept. 2007.
• Meinerling M (2008) Aerobic transformation of AHC-2102225 in soil. Unpublished report from IBACON, Rossdorf, Germany, Study Report No. 24878173, 09. July 2008. Meinerling M and Hermann S (2006a) Determination of water solubility of AHC 2102225.
• Unpublished report from IIBACON, Rossdorf, Germany, Study Report No. 28845186, 20. June 2006.
• Meinerling M and Hermann S (2006b) Determination of the partition coefficient (n- Octanol/Water) of AHC 2102225 by shake flask method. Unpublished report from IIBACON, Rossdorf, Germany, Study Report No. 28844185, 05. April 2006.
• Smeykal H (2006) AHC2102225 – Vapour pressure. Unpublished report from Siemens, Frankfurt am Main, Germany, Study Report No. 20060259-01, 28. August 2006.

https://www.fda.gov/media/95841/download

which means providing a science-based argument back to the FDA that their query is relevant to the outcomes of the proposed clinical trials.
It shows the real problem of MPL having been around for so long and used in so many animal testing studies.
MT clearly stated that we don't have that specific data, but how relevant is the FDA request for 'additional animal exposure data'??
Here's where the big guns on the SAB will step up with precise advice and perhaps a renowned toxicologist retained for consultancy,
And maybe Elanco will be a good corporate citizen and help out with appropriate information.
cheers,
Ice
And maybe the conspiracy theorists in the forum will speculate on what it means to do a deal with the Elanco devil!
Have a great week!