UCLA Develops 'Smart Bomb' Mouthwash Targeting Cavity-Causing Bacteria

What if a mouthwash could kill only the bacteria that cause cavities and leave everything else alone? A team at the UCLA School of Dentistry, led by Dr. Wenyuan Shi, chair of the section of oral biology, reported in November 2011 that they had done exactly that.

The mouthwash uses a technology Shi calls STAMP — specifically targeted antimicrobial peptides. The active ingredient, C16G2, is an engineered peptide designed to bind to and kill Streptococcus mutans, the principal cause of tooth decay, while sparing the hundreds of other bacterial species that live in the mouth. Conventional mouthwashes and broad-spectrum antibiotics kill indiscriminately — wiping out beneficial microbes alongside the harmful ones, and only for about 12 hours.

In a small clinical study of 12 subjects, published in the journal Caries Research (Vol. 45:5, pp. 415–428), a single rinse with the experimental mouthwash nearly eliminated S. mutans for the entire four-day testing period.

The work was supported by Colgate-Palmolive and by C3-Jian, a company Shi founded around patent rights he developed at UCLA, which were exclusively licensed to the company. Based on the trial results, C3-Jian filed an Investigational New Drug application with the U.S. Food and Drug Administration, with larger clinical trials expected to begin in March 2012.

To be clear about the limits: this was a small, early trial measuring bacterial levels over four days, not a lifetime of cavity immunity. Dental caries remains one of the most common and costly infectious diseases in the United States, affecting more than 50 percent of children and the vast majority of adults. A targeted anticaries treatment — potentially the first since fluoride was licensed decades earlier — would be significant. But the science here was a promising beginning, not a finished product.