tion's statutory authority.  He considered


22
the FDA construction ... reasonable, and consistent with the language of Sec. 512(e)(1)(E) of the Food, Drug and Cosmetic Act ..., which provides the primary source of FDA authority to approve supplemental NADA's:  "The supplemental application shall be treated in the same manner as the original application."    21 U.S.C. Sec. 360b(e)(1)(E) (1976).


23
The Act is to be construed liberally to effectuate its overriding purpose to protect the public health.    United States v. An Article of Drug ... Bacto-Unidisk, 394 U.S. 784, 798 [89 S.Ct. 1410, 1418, 22 L.Ed.2d 726] (1969).  The FDA's broad mandate to safeguard the public health thus affords it the flexibility to shape its administrative actions when it has reason to doubt the safety of a new animal drug....


24
....


25
There are bounds to the FDA's power to require a full safety and effectiveness review.  One cannot discern the basis for such an authority where the application demonstrates that the change has no bearing whatever on issues of safety or effectiveness.


26
Id. at 1380-81 (footnote omitted).  We find Judge Leventhal's analysis persuasive and adopt it as our own.  See also Chevron v. Natural Resources Defense Council, --- U.S. ----, 104 S.Ct. 2778, 2782, 81 L.Ed.2d 694 (1984) (deference to agency interpretation of statute).


27
Cyanamid makes several attempts to avoid the sting of the FDA's statutory authority construction.  The attempts fail.


28
Most imaginatively, Cyanamid argues that its request for OTC status is not covered at all by the Animal Drug Amendments, but rather is governed only by 21 U.S.C. Sec. 352(f)(1) and Sec. 353, sections that generally concern labeling and misbranding of drugs.  The argument is unconvincing.  Proban's new drug application is subject to change in accordance with the Animal Drug Amendments.  See Transitional Provisions, Pub.L. 90-399, Sec. 108(b)(2).  Section 512(e)(1)(E) of the Animal Drug Amendments, 21 U.S.C. Sec. 360b(e)(1)(E), provides that the FDA shall