Sutro Biopharma is pursuing a big idea for antibody drug development, and it just got some more money to see how far it can go.
The South San Francisco-based biotech company is announcing today it has received $16 million in the second tranche of its Series C financing. Skyline Ventures led the deal, which included Lilly Ventures, Amgen Ventures, SV Life Sciences, and Alta Partners. The company, which raised the first chunk of its Series C financing in November 2010, has now raised about $60 million since its founding in 2004.
Sutro, with technology from James Swartz’s lab at Stanford University, is honing a process for making biologic drugs without the traditionally messy business of incubating them in living cells. Sutro hopes to use a chemical synthesis process that can make biotech drugs in a way that’s faster, cheaper, and more reliable and scalable than cell-based methods of today. The company has set its sights high, looking to use this process to make some exotic new molecules like bi-specific antibodies that hit two molecular targets on cells instead of just one, and antibody drug conjugates, which link targeted antibodies to toxins as a way of creating souped-up “smart bomb” drugs.
“Although we generally remain cautious, especially when investing in earlier stage companies, we see the tremendous potential for antibody drug conjugates and bi-specific antibodies for drug development, particularly in cancer therapy,” said Leon Chen, a partner with Skyline Ventures, in a statement. “We believe that Sutro’s biochemical protein synthesis platform provides a unique opportunity to rapidly identify and develop next generation therapeutics that can be manufactured utilizing the same platform in accordance with current good manufacturing practices.”
Sutro is one of a long and growing list of biotech companies that are aspiring to make the next big technological leap in the engineering of protein drugs. Many companies have been emboldened by the example of Seattle Genetics and Genentech/ImmunoGen, which made headlines in the past couple years with successful antibody drug conjugate molecules that were the culmination of more than 30 years of difficult R&D. Now small companies like South San Francisco-based CytomX Therapeutics, San Diego-based Ambrx, Cambridge, MA-based Mersana Therapeutics, and Vancouver, BC-based Zymeworks are among the contenders looking to engineer targeted antibodies in new and improved ways.
For more on the Sutro technology, see the profile I wrote on the company from November 2010.