m unable to conclude that any grounds exist to overturn the ALJ's decision."    With some modifications, he affirmed the ALJ's findings and conclusions.  Proban Liquid:  Denial of Supplemental New Animal Drug Application, No. 33-606 (June 20, 1984) [hereinafter Commissioner's Decision] at 5.


18
Cyanamid now petitions this court to review and reverse the Commissioner's decision.

II. ANALYSIS
A.

19
Cyanamid dominantly argues that the FDA lacks statutory authority to conduct a full safety and effectiveness review before approving a supplemental NADA.  According to petitioner, the Administration must accept without renewed inspection the safety and effectiveness of an animal drug within the bounds of the previously approved NADA, and can investigate only the marginal difference between the original NADA and the supplemental NADA.  In this case, therefore, Cyanamid's interpretation would allow the FDA to consider only whether adequate directions for over-the-counter use can be written.  Brief for Petitioner at 46-52, 62-71.  We reject Cyanamid's position and uphold the FDA's thorough investigation as within its statutory authority.


20
The issue at hand is not novel in this court.  In Rhodia, Inc. v. Food and Drug Administration, 608 F.2d 1376 (D.C.Cir.1979), the FDA rejected Rhodia's supplemental NADA seeking to add an alternative bulk supplier of the active ingredient in Rhodia's product.  The FDA rejection of the supplemental NADA rested on new evidence calling into question the safety of the active ingredient.


21
The court did not reach the issue whether the FDA, as a general matter, had the authority to pursue a full safety and effectiveness review regarding the original NADA when considering a supplemental NADA.  Assuming that the FDA had such authority, the appellate panel found the administrative action in Rhodia's case arbitrary and capricious.   Id. at 1378-79.  In a separate statement, however, Judge Leventhal (also the author of the majority opinion) squarely addressed the question of the Administra