From Bloomberg Law:

The precedential Oct. 30 ruling by the U.S. Court of Appeals for the Federal Circuit suggests those patents must be written more narrowly, and it potentially exposes existing patents to new challenges from competitors in the field, said Charles Duan, a patent lawyer and director of technology and innovation for the R Street think tank in Washington, D.C.

“It opens up a new line of attack on existing drug patents,” Duan said

“The purpose of the enablement and written description requirements is to ensure that the public is not burdened with over-broad patents when the inventor has actually revealed only a few examples of use,” Duan said.

“I’d anticipate seeing many more written description and enablement challenges,” he added.

“Now, a drugmaker might conduct research on alternate forms of an existing drug with less fear” that a broadly written patent will sweep up those alternate formulations, Duan said.