Pharma Giants Look for New Cancer Treatments in Human Waste

Companies seek ways to harness gut bugs for immune therapies

New research has suggested a link between the trillions of bacteria that inhabit the human bowels and the efficacy of immune therapies. Now, at least a half-dozen biotech start ups are competing to turn that science into commercial products that target the immune system via the gut; at least two companies aim to begin testing experimental treatments on patients by next year, according to an article posted on the Bloomberg website.

Investors ranging from venture capitalists to pharma giants Bristol-Myers and Johnson & Johnson have pledged at least $125 million to cancer microbiome start ups, the article says. Clustered around Paris and Boston, these new companies have analyzed tens of thousands of stool samples, which are mostly bacteria from the wall of the gastrointestinal tract.

The gut microbiome’s link to immune therapies was first identified in two pioneering research papers published in 2015. One showed how fecal transplants from human patients treated with an immune oncology drug enhanced the medication’s effectiveness in mice. The other found that certain bacteria combined with a second immune drug froze tumor growth.

The bacterial ecosystem may help doctors reach three key goals to make immune therapies work better, according to the article. The first is to better determine who can be helped. Second is how to tweak the body’s immune defenses so more patients can respond to treatment. And third is how to prevent a common adverse effect: the immune system attacking the gut. Further off would be a treatment that leverages gut bacteria to fight or even prevent cancer.

It’s still unclear which bugs are most beneficial and whether it’s better to place them in the body via a fecal transplant or an oral pill, the article notes. The scientific challenge will be to identify the “best ecosystem,” a combination of bacteria that’s effective and not toxic.

In oncology, the goal is to “perturb the immune system in a beneficial way,” rousing it into action to attack cancer cells, said David Cook, chief scientific officer at Seres Therapeutics. “There’s some indirect evidence—but very strong indirect evidence—that the microbiome can do that.”

Source: Bloomberg Technology; June 14, 2017.