A range disclosed in the prior art does not anticipate a claimed invention falling within that range when it can be shown that there is material and unpredictable variation across the range. Here, for example, a prior art disclosure of a composition comprising 0.001%–1% bimatoprost and 0–1000 ppm of a preservative was found to be insufficient to anticipate a 0.01% / 200 ppm claimed composition because “the claimed amounts of the two different ingredients could and did materially and unpredictably alter the property of the claimed formulation.” “[W]here there is a range disclosed in the prior art, and the claimed invention falls within that range, a relevant inquiry is whether there would have been a motivation to select the claimed composition from the prior art ranges.” This would be a good case to consult and cite in response to an anticipation rejection predicated on an overly broad disclosure in the prior art.
Background / Facts: The patents being asserted here in response to a generic drug ANDA submission are directed to a pharmaceutical composition for treating glaucoma or ocular hypertension that comprises around 0.01% bimatoprost and 200 ppm preservative benzalkonium chloride (“BAK”), among other ingredients. This formulation is purported to be a surprising improvement on a previous dosing that included a higher 0.03% concentration of bimatoprost and a lower 100 ppm concentration of BAK but suffered from substantial side effects. Although the prior art does not teach the particular claimed combination of amounts of bimatoprost and BAK, these amounts do fall within the ranges disclosed in a single reference describing a composition comprising 0.001%–1% bimatoprost and 0–1000 ppm of a preservative, including BAK.
Issue(s): Whether a motivation to pursue the claimed formulation and a reasonable expectation of success in doing so must be established even though the claimed amounts of bimatoprost and BAK fall within prior art ranges.
Holding(s): Yes. “[W]here there is a range disclosed in the prior art, and the claimed invention falls within that range, a relevant inquiry is whether there would have been a motivation to select the claimed composition from the prior art ranges. … Here in this case, the prior art ranges are broad[] … and the record shows that the claimed amounts of the two different ingredients could and did materially and unpredictably alter the property of the claimed formulation.” Moreover, “the prior art taught that BAK should be minimized in ophthalmic formulations to avoid safety problems” and “that BAK would not increase the permeability of bimatoprost, but might instead decrease it.” “[T]hose known side effects would have discouraged a person of ordinary skill from using higher concentrations of BAK in a bimatoprost formulation, especially when 50 ppm BAK was known to be an adequate preservative in [other dosing]. … The record thus shows that the prior art ‘criticize[d], discredit[ed], or otherwise discourage[d]’ the use of 200 ppm BAK in a bimatoprost formulation.”