It isn't very often that an agency sometimes accused of over-regulating an industry can be ridiculed for not regulating enough, but that's exactly where the Food and Drug Administration finds itself. And this time the criticism is coming from pharmaceutical companies themselves. Companies developing generic biologic drugs, which are often costlier and more complicated to manufacture than small molecules, have only loose guidelines on what the agency wants to see for approval. Additionally, the Biosimilar User Fee Act of 2012 -- meant to clarify development procedures -- only made things worse.

The problem gets even worse when you consider that the European Medicine Agency has a clear-cut roadmap for biosimilar drugs. In fact, more than a dozen of the generics have been approved on the continent. Why should cheaper treatments be available in one market and not another due to a simple lack of communication?

The market opportunity in the United States could be huge. Take a look at some of the top biosimilar companies waiting for the FDA to make up its mind.  

  1. Amgen (NASDAQ:AMGN) is looking to launch six biosimilars beginning in 2017 for drugs such as Herceptin, Humira, Remicade, and Rituxan. The company believes biosimilars represent a multibillion-dollar opportunity.  
  2. Momenta (NASDAQ:MNTA) and Baxter (NYSE:BAX) are collaborating on up to six biosimilars for autoimmune diseases and oncology. Three have already been identified, and one should have an investigational new drug application submitted next year.
  3. Novartis (NYSE:NVS) wants its generic business, Sandoz, to cement its role as a world-leading biosimilar company. Already controlling half of the global biosimilar market, Sandoz is currently developing 10 molecules to add to its portfolio.  
  4. Hospira (NYSE: HSP) offers services ranging from contract manufacturing to software, but it, too, wants to add a biosimilar program. The company is developing generic versions of Epogen, Herceptin, Neulasta, Neupogen, and Remicade.

There is a lot at stake, and plenty of companies that are nudging the FDA clear things up. In the following video, Fool contributor Maxx Chatsko breaks down the industry's frustration and what can be done to resolve the issue.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.