One of the big questions about establishing a regulatory pathway for approving biologics is the extent to which the FDA will require clinical trials to prove a biosimilar is equivalent to the original brand medicine. This is what is called the great unknown. But the FDA may have sent a signal about its thinking with a decision concerning a Teva Pharmaceutical drug.

The FDA issued a Complete Response Letter to Teva, which has been seeking approval to sell a version of Amgen’s Neupogen, a med used to treat infections in people with certain types of cancer. In its press release, Teva notes the FDA “does not require additional pre-marketing clinical trials to complete the review” of the application.

This is the part that is interesting, since Teva had submitted its application to the FDA before the approval process has been sorted out. Yet as EyeOnFDA points out, the agency has just offered up an instance in which additional trials will not be necessary. This is the second time in recent months when the FDA has surprised everyone by not requiring as much clinical work as expected. The other instance involved a version of Lovenox (see here).

One additional point worth noting: the Teva drug has already been approved by the European Union, which is ahead of the US in establishing a regulatory pathway for endorsing biologics. Whether this suggests the FDA was looking toward their counterparts across the pond in this instance, however, is not clear. Meanwhile, the agency will hold a two-day meeting about similars in November.