Drug companies are fighting doctors and patient advocates over the definition of fecal microbiota used in transplants for the treatment of Clostridioides difficile.

 Clostridioides difficile is an infectious bacteria that affects half a million Americans each year and kills 30,000 of them. A new treatment that involves the transfer of fecal matter from healthy donors into the bowels of infected patients restores the function of their gut microbes. In addition to the use of fecal microbiota transplants (FMT) for the treatment of Clostridioides difficile, there is potential for the technique to be effective in other diseases, including cancer, diabetes, obesity, autism, ulcerative colitis and Alzheimer’s and Parkinson’s diseases.

There is a battle underway regarding FMT, however, that will impact how the U.S. Food and Drug Administration (FDA) regulates the procedure, how much it costs and who gets to profit. The question relates to whether the fecal microbiota should be classified as a drug or considered to be more like the organs, tissues and blood product that are commonly transferred from healthy donors to sick patients.

In a draft decision in 2013, the FDA indicated that it would regulate FMT as a drug but would continue studying the issue before making a final decision, which is expected soon. Opponents of this approach say it is based on outdated science and will only lead to higher costs for patients. Currently, most fecal microbiota material is provided by OpenBiome, a nonprofit public stool bank in Cambridge, MA. In addition, they say this decision could impact the development of future therapies based on the human microbiome if drug companies are allowed to control development and pricing. Recently, more than 40 prominent gastroenterologists and infectious disease doctors wrote to the agency, urging it to rethink its approach.

The pharmaceutical companies invested in the development of FMT-based treatments, as well as some doctors, claim that the drug designation is needed to ensure the safety and efficacy of this type of therapy.

Others, including experts in bioethics and many doctors, would like to see the FDA establish a new regulatory category that reflects the groundbreaking nature of microbiota therapies.