In Re Couvaras, No. 22-1489 (Fed. Cir. 2023)Annotate this Case
The pending claims of the 422 application recite methods of increasing prostacyclin release in the systemic blood vessels of a human with essential hypertension to improve vasodilation. Increased prostacyclin release is achieved by co-administering two well-known antihypertensive agents: a GABA-a agonist and an Angiotensin II Receptor Blocker (ARB). Essentially, the claims relate to combatting hypertension with known anti-hypertensive agents and claiming their previously unappreciated mechanism of action. During prosecution, Couvaras conceded that GABA-a agonists and ARBs “have been known as essential hypertension treatments" for decades. The Examiner agreed, citing 10 references establishing that GABA-a agonists and ARBs lower blood pressure; the claimed results of increased prostacyclin release, activation of uninhibited GABA-a receptors, and smooth muscle relaxation were not patentable because they naturally flowed from the claimed administration of the known antihypertensive agents.
The Patent Board affirmed the rejection, holding that the claimed result of an increased prostacyclin release was inherent in the obvious administration of the two known antihypertension agents and that Couvaras’s objective indicia arguments did not overcome
the prima facie case of obviousness. The Federal Circuit affirmed, rejecting arguments that the Board erred in affirming that a skilled artisan would have had motivation to combine the art; that the claimed mechanism of action was unexpected, and that the Board erred in discounting its patentable weight; and that the Board erred in weighing objective indicia of nonobviousness.