Ten years have gone by since Susan Froshauer co-founded Rib-X Pharmaceuticals to create effective new antibiotics. If things break right, this will be the year her company makes some critical decisions that could ensure it lasts 10 more.
Like a lot of startup drug companies, this one is consuming a lot of time and money. The New Haven, CT-based firm raised $35 million over the past year, bringing its total financing to $158 million since its founding in 2000. Much of that cash is being set aside to test Rib-X’s lead candidate, delafloxacin, in a study of 800 patients with antibiotic-resistant infections they picked up in the hospital. If Rib-X can get help from a Big Pharma partner to start that trial on schedule this year, and it pans out, then the startup should be able to file an application to market the drug with the FDA in 2012, Froshauer says.
Rib-X’s antibiotic passed a mid-stage study of 150 patients in January 2009. The drug was well-tolerated, and helped more than 90 percent of patients become clinically cured of complex skin infections, even when more than half had dangerous and hard-to-treat MRSA infections. The treatment showed comparable effectiveness when stacked up against Pfizer’s tigecycline (Tygacil). If Rib-X can match that result in the pivotal study being planned, it could offer a new option for doctors in the constant battle against bacterial resistance. It could also be a first step for Rib-X’s transition from an R&D operation into something bigger and enduring.
“By partnering the delafloxacin asset, we’d be in a situation to continue to grow the program, and over time will allow us to have an antibiotic company,” Froshauer says.
Rib-X has been around as long as it has because of the promise of its unusual scientific approach to developing antibiotics. The vision was to use emerging technology to get high-resolution crystal structures of structures called ribosomes in bacterial cells. This is important because many different classes of antibiotics work by binding with the ribosomes. So by getting precise images, and using a proprietary computational system, Rib-X seeks to identify points where the bacteria are vulnerable, and where resistance can emerge.
While the underlying science is getting a taste of validation from clinical trials, that’s not the end goal for Rib-X as a business, Froshauer says. Other firms that have achieved some clinical validation have capitalized on that in subsequent acquisitions—San Diego-based Calixa Therapeutics, for instance, sold out last year to Lexington, MA-based Cubist Pharmaceuticals for