FDA New Drug Approvals Don’t Sanction Impurities, Court Says (1)

Regulatory approval of a new drug greenlights its active ingredient, but doesn’t sanction its impurities, a US appeals court ruled Tuesday.

The court rejected Novartis AG’s bid to get new chemical entity exclusivity for Sanofi’s Aubagio pulled, which would have secured its Sandoz Inc. unit six months of exclusivity for its copy of the multiple sclerosis drug.

When the US Food and Drug Administration approved Aubagio in 2012, it determined it hadn’t previously approved the drug’s active ingredient, teriflunomide, in any other drug. That meant Aubagio was eligible for a period of exclusivity as a “new chemical entity”—a designation that ...