As to whether TorPharm was still entitled to its paragraph IV certification, the FDA's concluded that — in light of Purepac, as well as the Federal Circuit's decision in Warner-Lambert and Pfizer's December 13 letter — a section viii statement, rather than a paragraph IV certification, was appropriate for the '479 patent. (A.R., tab 18 at 4-5.) While the Court is concerned about the Decision Letter's references to Warner-Lambert,*fn15 this unfortunate aspect of the letter does not require that the agency's decision be vacated. For, despite the haze created by the letter's imprecise language, the Court can readily "discern the path" that the agency intended to travel. See Bowman Transp., Inc. v. Arkansas-Best Freight Sys., 419 U.S. 281, 286, 95 S.Ct. 438, 42 L.Ed.2d 447 (1974) (court "will uphold a decision of less than ideal clarity if the agency's path may be reasonably discerned"). And, because the FDA's conclusion comfortably and correctly rests on that basis, reversal and remand are not required. See FEC v. Legi-Tech, Inc., 75 F.3d 704 708-09 (D.C. Cir. 1996) (affirming the proposition that "remand to the agency is an unnecessary formality where the outcome is clear"); Am. Fed. of Gvm't Employees v. Fed. Labor Relations Auth., 778 F.2d 850, 862 n. 19 (D.C. Cir. 1985) (citing cases for this proposition); NLRB v. Am. Geri-Care, Inc., 697 F.2d 56, 64 (2d Cir. 1982) (holding that even where the agency assigns the wrong reason for its actions, reversal and remand are required "only where there is a significant chance that but for the error, the agency might have reached a different result").
As noted above, the FDA has long taken the position that paragraph IV certifications and section viii statements are mutually exclusive. In Purepac, the Court called attention to this view, but observed:
[A]t oral argument, the agency stated that it has not
taken a definitive position as to whether equitable
considerations might ultimately persuade it to allow
two applicants to submit a certification and a
statement, respectively, with respect to the same
patent. As such, the FDA has not decided whether it
could, or would, approve TorPharm's application with
a paragraph IV certification to the '479 patent even
if the Court were to direct the agency to accept
Purepac's application with a section viii statement.
238 F. Supp.2d at 211. Allowing the agency to make this decision was in fact the very purpose for which the case was remanded. In this light, the Court reads the Decision Letter as ultimately expressing the FDA's view that whatever equities may exist in this case, they were not sufficiently compelling to persuade the agency to make an exception to its well-established position that where a section viii statement is appropriate, a paragraph IV certification is not. This is reflected in the Decision Letter's insistence that an "applicant does not have the option of making a paragraph IV certification in lieu of, or in addition to, a section viii statement; either the ANDA applicant is seeking approval for the use claimed in the patent, or it is not." (A.R., tab 18 at 4.)
In other words, then, once this Court had decided that Purepac could use a section viii statement — a substantive conclusion with which the Decision Letter signals agreement (A.R., tab 18 at 4-5) — the agency found no reason to depart from its rule and allow any other applicant to maintain a paragraph IV certification.*fn16 Refusing to make an equitable exception from this rule was within the FDA's discretion, and TorPharm has pointed to nothing in the statute or regulations to cast doubt on the rule itself. Moreover, even if that rule has not been embodied in a formal regulation, it is still entitled to judicial deference in the absence of some indication that it conflicts with any of the constraints on the agency's regulatory authority, is inconsistent with the agency's own prior pronouncements, or is otherwise poorly reasoned or unpersuasive. See United States v. Mead Corp., 533 U.S. 218, 234-35, 121 S.Ct. 2164, 150 L.Ed.2d 292 (2001) (holding that even informal agency interpretations not entitled to Chevron deference are nonetheless entitled to some "persuasive force") (citing Metropolitan Stevedore Co. v. Rambo, 521 U.S. 121, 136, 117 S.Ct. 1953, 138 L.Ed.2d 327 (1997)). There are no such indications here.
From this conclusion, the rest of the agency's actions follow readily. Once TorPharm's paragraph IV certification was deemed improper in light of Purepac's section viii statement, which the FDA was compelled to accept, the agency had two options. First, it could have required TorPharm to submit its own section viii statement to replace the rejected paragraph IV. Alternatively, it could have done as it did and removed the patent from the Orange Book altogether, for the prospect of exclusivity on the '479 patent had been vitiated by the determination that TorPharm could no longer use a paragraph IV certification, and the delisting regulation posed no impediment to striking the patent from the agency's records. For exclusivity purposes, however, there is no functional difference between these options, for either way TorPharm's claim to exclusivity based on the '479 patent is extinguished.*fn17 Accordingly, because the Court finds that the FDA acted reasonably in not departing from its well-settled rule that a section viii statement and paragraph IV certification cannot be filed as to the same patent, the agency's corresponding conclusion that no applicant was entitled to exclusivity on the '479 patent must be upheld as well.*fn18
Finally, the Court rejects TorPharm's argument that the FDA's disallowance of the paragraph IV certification was inconsistent with the agency's actions regarding certifications made by ANDA applicants in the case of the drug mirtazapine. (TorPharm's Mem. at 26-28.) Whatever similarities may exist between the circumstances of mirtazapine and those of gabapentin, one crucial difference remains: in the former case, there was no court decision requiring the FDA to accept a section viii statement with respect to the patent in question. Thus, in deciding what to do there, the agency's regulatory role was not constrained, as it was here, by an injunction requiring it to accept the section viii statement submitted by one applicant. Accordingly, the fact that the agency allowed the mirtazapine applicants to use paragraph IV certifications to a method-of-use patent that did not claim an approved use of the drug does not compel the agency to do the same in this case. Whatever the merits of the agency's determination regarding the '099 patent, that determination certainly does not stand for the proposition that the FDA will allow one generic applicant to use a section viii statement while allowing another applicant to use paragraph IV certification to the same patent.
And, while TorPharm is correct that this Court's opinion in Purepac did not, by its terms, compel the FDA to reject the paragraph IV certification (TorPharm's Reply Br. at 20-21), this hardly means that the Purepac decision is irrelevant in distinguishing gabapentin from mirtazapine. The reason that the Court did not take that step was that the agency had not yet made a final decision whether it would, or could, make an exception to its general rule that section viii and paragraph IV are mutually incompatible. While the Court took note of this window, it did not instruct the agency to leave it open. The FDA's subsequent decision to definitively slam it shut was thus entirely consistent with the Court's remand order. And, once the agency decided that its long-standing rule would apply, a decision that TorPharm has not shown to be unreasonable, it followed inexorably from the terms of the Court's injunction that TorPharm would be required to withdraw its certification. As such, the Purepac decision is sufficient to distinguish the result reached in the Decision Letter from the conclusions the agency reached with respect to mirtazapine. The mere fact that paragraph IV certifications were permitted there provides no basis for requiring the FDA to allow them here.
For the reasons given above, the FDA's conclusion that Purepac was the first ANDA applicant to submit an effective paragraph IV certification to the '482 patent was reasonable. So too was the agency's determination that no applicant was entitled to submit a paragraph IV certification to the '479 patent. Accordingly, the agency properly held that Purepac, and Purepac alone, is entitled to 180-day exclusivity to market a generic version of gabapentin.