Monte Rosa rakes in $96M Series B as it prepares 'molecular glue' platform for IND-enabling studies
About four months after completing an extension to its Series A, Monte Rosa Therapeutics is putting its next foot forward with another heap of cash.
The Boston-based biotech is back with $96 million in Series B financing with a goal to get its lead program ready for IND-enabling studies by the end of the year. Though Monte Rosa is keeping its specific target a secret for now, the company has been researching how to utilize its protein degradation technology in breast cancer and non-small cell lung cancer, among other areas.
“It’s a protein that we’ve found to be essential in mediating the activity of a transcription factor, one that the field has tried to find medicines for for quite a while,” CEO Markus Warmuth told Endpoints News. “Because of the breadth of cancers that are dependent on that, it could be very broad.”
Wednesday’s round was led by Aisling, with Versant and New Enterprise Associates participating once again. New investors included HBM, Cormorant, GV, Amzak Health, Casdin Capital, Sixty Degree Capital and Cambridge Asset Management.
Monte Rosa’s platform revolves around developing “molecular glues” that can reprogram ubiquitin ligases central to protein degradation. By taking control of this process, the biotech hopes to redirect the body’s natural degradation efforts and eliminate the proteins altogether rather than merely inhibit their functions.
Historically, Warmuth said, many drugs have attempted to follow the inhibition method, but that requires targets to have an active site. Monte Rosa’s molecular glues allow the biotech to go after targets that don’t have such sites, especially when it comes to the notoriously difficult area of transcription.
“Part of the excitement around our platform is we can finally go very systematically after transcription, with few exceptions,” Warmuth said. “Trying to go after the interaction between a transcription factor and DNA has been inherently difficult, and so this molecular glue-based platform that we have really offers up that opportunity.”
Warmuth compared Monte Rosa’s approach with that of PROTACs, which he described as a scaffold, with one part binding to the ubiquitin ligase and the other to the target of interest, connected to a hydrophobic linker that unites those two paths. Though that makes the molecules relatively big, this helps it induce changes within the ligases that ultimately drive the disease-fighting function.
The best known example of a glue-based degrader is lenalidomide, the multiple myeloma chemotherapy drug made by Celgene, Warmuth said. In this approach, two transcription factors are glued together to the ligase and transformed into the “perfect shape” to be destroyed in helping treat the cancer.
Protein degradation itself isn’t all that new, but money has poured into the area recently and especially this year. Back in March, the biotechs Kymera and Nurix combined to raise $220 million on back-to-back days, and both went public over the summer. Currently, only Arvinas’ protein degraders, an androgen receptor-targeting drug for prostate cancer and an estrogen receptor-targeting drug for breast cancer, have reached the clinic, getting into human testing in 2019.
But what Warmuth hopes separates Monte Rosa from the pack is the specific focus on their glue-based technology. Despite keeping information about their lead program — as well as the rest of their pipeline — close to the chest, Warmuth expressed confidence in the platform and the team his company has assembled.
“The reason why we’re focusing on it is really this promise of now going after pre-clinically validated targets, things we’ve always wanted to go after but have escaped because there’s no druggable site,” Warmuth said. “That’s really what distinguishes us from the field scientifically.”