Addressing obviousness issues, the U.S. Court of Appeals for the Federal Circuit affirmed a lower court’s finding that patents were valid and infringed, despite undeniably including recitations falling within a prior art range. Allergan, Inc. v. Sandoz Inc., Case No. 14-1275 (Fed. Cir., Aug. 4, 2015) (Lourie, J.)
Allergan owns five patents related to Lumigan® 0.01% (“Lumigan 0.01%”), a glaucoma treatment product having 0.01% of bimatoprost and 200 ppm of benzalkonium chloride (BAK). Several companies filed Abbreviated New Drug Application (ANDA) applications for generic versions of Lumigan 0.01% (collectively ANDA applicants), causing Allergan to file a patent infringement lawsuit. After a bench trial, the district court held that Allergan’s patents were not invalid for obviousness, lack of written description or lack of enablement and were infringed, entitling Allergan to a permanent injunction. The ANDA applicants appealed.
Before the Federal Circuit, the ANDA applicants argued that the Allergan patents were invalid because the claimed amounts of bimatoprost and BAK in Lumigan 0.01% fell within prior art ranges and that there was no evidence of unexpected results. The ANDA applicants also argued that Allergan’s claims failed to meet written description and enablement requirements because they did not disclose any efficacy or hyperemia data of Lumigan 0.01%.
Addressing the obviousness issue, the Federal Circuit acknowledged that the asserted prior art disclosed a composition comprising 0.001%-1% of bimatoprost and 0-1000 ppm of a preservative, such as BAK, and that Lumigan 0.01% fell within the prior art ranges. However, the Court explained that even where a claimed invention falls within a prior art range, invalidity does not necessarily follow. Rather, the relevant inquiry is whether motivation existed to select the claimed composition. Here, the prior art taught away from the claimed invention, and the claimed invention exhibited new and unexpected results. Specifically, the prior art taught that BAK should be minimized in ophthalmic formulations to avoid safety concerns and that reducing the amount of bimatoprost below 0.03% would significantly diminish efficacy. Additionally, the prior art taught that an increase in BAK would result in hyperemia at high concentrations and would not increase the permeability of bimatoprost.
An inference of non-obviousness is especially heightened where the prior art’s teaching undermines the reason being proffered as to why one skilled in the art would have combined known elements. Here, although the prior art ranges covered the claimed invention, the prior art discredited and discouraged the use of 0.01% bimatoprost in combination with 200 ppm BAK for ophthalmic use. Furthermore, the unexpected results of enhanced bimatoprost permeability and reduced hyperemia without affecting efficacy were differences in kind, not merely degree, because the results were completely opposite to that taught by the prior art.
As for the ANDA applicants’ lack of enablement and written description arguments, the Federal Circuit again sided with Allergan. The specifications of Allergan’s patents described Lumigan 0.01%’s exact formulation as one of the best modes of the invention. Although the specifications did not explicitly describe the clinical efficacy and hyperemia profile of Lumigan 0.01%, the inherent properties of the formulation necessarily would produce the claimed clinical profile of lowering intraocular pressure and reducing hyperemia as compared to Lumigan 0.03%. Indeed, a claim that recites a property that is necessarily inherent in an adequately described formulation does not lack written description merely because the property itself is not explicitly described. Moreover, the Court observed that while a patent need not guarantee that the invention works to satisfy enablement and patents do not even generally require efficacy data, in this instance Allergan’s patents included specific composition formulations, actual in vitro and in vivo data, and a constructive example, all supporting enablement.