The CAFC case of Rajagopalan involves the topic of illicit manufacture of methamphetamine from pseudoephedrine

The CAFC does organic chemistry in Rajagopalan :

The ’191 application describes a composition that “prevent[s] [the] illicit manufacture of methamphetamine” from pseudoephedrine, a common pharmaceutical ingredient in over-the-counter allergy medication. J.A. 22. The application explains the basic two steps in the manufacture of methamphetamine from such available medications. The first step is isolation, or extraction, of the pseudoephedrine from the available medications, which contain other components. The second step is a chemical “reduction” reaction, involving reducing agents that donate electrons to the pseudoephedrine to produce methamphetamine. J.A. 23. The application discloses a pseudoephedrine composition that impedes the second (reduction) step of that conversion process. Specifically, it discloses a combination of pseudoephedrine with a food-flavoring excipient (an additive), J.A. 23, in which the “excipient may capture the electrons from the reducing agent . . . at a much higher rate than pseudoephedrine . . . thereby blocking the formation of methamphetamine,” J.A. 25. These food-flavoring excipients are referred to in the ’191 application as “organoleptic agents.” J.A. 23.

The In re Best case shows up

In this circumstance, “the burden shifts to the patentee to provide evidence” to rebut the examiner’s prima facie case—here, specifically, to show that the claimed inhibition of reduction would not result. See In re Brandt, 886 F.3d 1171, 1176 (Fed. Cir. 2018); ACCO Brands Corp. v. Fellowes, Inc., 813 F.3d 1361, 1365–66 (Fed. Cir. 2016); In re Best, 562 F.2d 1252, 1255 (CCPA 1977). Mr. Rajagopalan has not undermined the Board’s determination that he did not rebut the prima facie case.