Rebiotix has raised $8.5 million in a $10 million offering, according to a regulatory document that the company filed yesterday with the SEC.

The offering, which consists of debt and convertible promissory notes, has garnered participation from 29 investors thus far, the company reported. Rebiotix said it is accepting minimum investments of $25,000 and that it doesn’t expect the offering to extend beyond a year.

The 32-person company, based in Roseville, Minn., is developing a microbiome-based therapy to prevent recurrent Clostridium difficile infection. Its Microbiota Restoration Therapy, which is delivered via enema or a lyophilized, non-frozen oral capsule, is designed to supply a patient’s intestinal tract with an array of healthy, human-derived microbes.

Rebiotix announced in August that the first patient was treated in a Phase III trial of its lead drug, RBX2660. The late-stage trial is designed to assess the therapy’s ability to prevent recurrent C. diff. infection for eight weeks compared to a placebo.

In one Phase II trial, 87% of patients who received RBX2660 had no C. diff. recurrence after eight weeks.

The sometimes-fatal gastrointestinal disease comes along with a variety of severe symptoms, including fever and diarrhea. More than 500,000 people are infected annually with C. diff., according to Rebiotix, and up to 30% of C. diff. patients experience more than one episode and need repeat treatment.

“The key is that there’s an underlying condition generally that’s caused them to be susceptible to C. diff. in the first place,” Rebiotix founder & president Lee Jones told Drug Delivery Business News. “So what we’re doing with this disease is we’re dealing with the whole person.”

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