Stealthy MIT Spinout Ribon, Led by a Sanofi Vet, Takes Aim at Cancer

Xconomy Boston — 

Two years ago, AstraZeneca became the first company to win approval of a new type of cancer drug known as a “PARP” inhibitor. A lot of competition has followed suit, and now it looks as if a new startup from MIT called Ribon Therapeutics—headed by a former Sanofi executive and backed by three different venture firms—has joined the scrum.

Ribon has yet to make a public announcement about its existence, though it does have a website and a small team, has already secured at least $10 million in venture financing, and has put out some information as to the drugs it aims to develop.

First, its website shows it’s based in Lexington, MA, at the address for the Ledgemont Technology Center, a five-building complex that houses several other biotechs, including Concert Pharmaceuticals (NASDAQ: CNCE), Pulmatrix (NASDAQ: PULM), and Xenetic Biosciences.

The company’s three scientific founders are Paul Chang, who up until recently was an assistant professor of MIT; Lee Kraus of University of Texas Southwestern Medical Center; and Tim Mitchison of Harvard Medical School. Chang’s LinkedIn page shows that he left MIT late last year to lead Ribon’s discovery efforts, and co-founded the company with Kraus and Mitchison.

The company also appears to have raised $10 million in venture funding in December and is seeking another $11 million, according to a regulatory filing. The filing shows that the startup has board members who come from venture firms from both the West and East Coasts: U.S. Venture Partners and The Column Group (Menlo Park, CA, and San Francisco, respectively), and Osage University Partners (Bala Cynwyd, PA). U.S. Venture’s Jonathan Root, Column Group’s Laurence Lasky, and Osage’s Bill Harrington are all listed in a Form D filing as directors.

Victoria Richon is the startup’s president and chief scientific officer, according to her LinkedIn page. She joined in November, leaving Sanofi, where she’d been a cancer drug discovery executive since 2012. Richon previously had stints at Cambridge, MA-based Epizyme (NASDAQ: EPZM) and Merck. She started working at Merck in 2006 after it acquired a startup she’d co-founded, Aton Pharma, which developed the cancer drug vorinostat (Zolinza).

LinkedIn profiles indicate Ribon has recruited at least four others with ties to Epizyme, where Richon worked from 2008 to 2012 as a drug discovery executive: among them Kevin Kuntz, Tim Wigle, Heike Keilhack, and Christina Majer.

The only thing Ribon has revealed publicly about its plan—via this LinkedIn page and a bio of Richon tied to an upcoming medical meeting—is that it aims to develop cancer drugs that target specific types of poly ADP-ribose polymerase, or PARPs. These are enzymes that help cells respond to DNA damage and repair themselves. Chang’s lab at MIT worked on better understanding the function of PARPs.

PARPs have become a popular target for a number of experimental cancer drugs in recent years, because blocking their activity hampers the ability of cancer cells to repair their DNA after the DNA has been damaged by, say, chemotherapy. The idea is that the PARP inhibitor then prevents tumor cells from repairing the damage. (Here’s more on PARP inhibitors from Clinical Advances in Hematology & Oncology.)

The field overcame a big setback in 2011, when a highly touted drug from Sanofi, iniparib, failed a late-stage trial in breast cancer. Iniparib had been the most advanced PARP drug in development.

PARP drugs have since rebounded. AstraZeneca won FDA approval of the first PARP-blocking drug, olaparib (Lynparza) for certain forms of ovarian cancer in 2014. AstraZeneca is also exploring its use in other cancers of the prostate, breast, pancreas, and stomach, and there are several rival drugs in development from companies like AbbVie (veliparib), Clovis Oncology (rucaparib), Tesaro (niraparib), and Medivation (talazoparib, acquired from BioMarin Pharmaceutical). Yet their reach remains limited, at this point. AstraZeneca’s drug is only approved for ovarian cancer patients whose tumors have certain genetic signatures—defective BRCA genes—that are thought to also mess with the DNA repair process. About 10 to 15 percent of ovarian cancer patients have these mutations.

Though it’s unclear exactly how Ribon is advancing the concept, one recent bio of Richon published on the American Association for Cancer Research’s website noted that the company is developing drugs aimed at specific type of PARPs.

Xconomy made several attempts to contact company leaders and investors. They either declined to return messages or declined to comment. We’ll post an update if we uncover any new information.