Megha Satyanarayana reports:

Matthew Redinbo remembers the day he entered the murky waters of the gut microbiome. He had popped in to say hi to Lisa Benkowski, a colleague in the Chemistry Department at the University of North Carolina at Chapel Hill. It was 2002, Benkowski had colon cancer, and she was taking a powerful chemotherapy called irinotecan.

“She said the side effects were a nightmare,” Redinbo says, describing how a large number of people on the drug, marketed as Camptosar, suffer from diarrhea and nausea. “Some days she could not get out of bed and certainly could not leave the house.”

Their conversation stayed with him. Why were irinotecan’s side effects so debilitating? Could they be prevented? The answers, Redinbo would find out, were hidden in the bacteria in our intestines.

As they study microbiome-drug interactions, researchers are learning not only that intestinal microbes dine on a great many of the small-molecule drugs that we take—those like irinotecan—but also that what the microbes are doing to those drugs may affect whether they work and whether they are safe. Yet with rare exceptions, we still know little about how these bugs slice and dice our medications and what happens to the fragments they leave behind. The reactions happening within our guts could reshape the way drugmakers create and test medicinal compounds.

“I’ve talked to a couple of companies about what I can do to help them test stuff, and then I don’t hear from them again,” says Nichole Klatt, a researcher at the University of Miami who has found that vaginal microbes deactivate HIV drugs. “So, do they care? I don’t know. Should they care? I think definitely yes because I think this has a much bigger impact on human health than people ever could have imagined.” [Continue reading…]