Phillips left C4 in 2020 and joined Cormorant, where he worked with later-stage biotechs. But he wanted to return to the startup world and was drawn to the idea of building a company around covalent drugs, or medicines that firmly lock onto their targets. He was already talking with Carlo Rizzuto, a managing director at Versant who he knew from serving together on two other companies’ boards of directors. By August, Phillips had begun working on what would become Nexo, which has facilities in Colorado and Massachusetts. Nexo, which in Portuguese means “connection,” is “at the intersection of emerging science, drug discovery, academia and biotech, where we think we can create value,” Phillips said.
The company said its technology can better identify promising compounds, particularly against targets that historically haven’t been easy to reach with covalent drugs.
Typically, these medicines bind in some fashion to the amino acid cysteine on their target protein. But cysteine isn’t always present or easy to aim at, limiting how covalent drugs can be deployed. Scientists at Nexo believed their technology could help them move beyond cysteine-based binding. With its approach, Nexo is taking part in a wave of new research to more thoughtfully design covalent drugs, which historically were often discovered by accident. These drugs, which include common medicines like aspirin and penicillin, tightly bind to their targets. Those strong bonds can mean a more potent drug effect, but they also increase the challenge of finding the right target as well as raise the risk of more serious side effects.
Nexo has not disclosed which cancers it is targeting, and may explore other diseases in the future. The collaboration with MD Anderson gives Nexo access to the Houston-based research center’s tumor models and clinical knowledge. “It’s hard to build 100 years of institutional knowledge when you’re a startup, so that’s what we get from making that partnership,” Rizzuto said.
Recently, biotech investors appeared to have cooled on oncology biotechs. Only 10 cancer drugmakers have priced initial public offerings over the past two years, compared to nearly 90 in the two years prior, according to BioPharma Dive data. “The pendulum has swung in terms of investor appetite,” Rizzuto said. The fallout from the Inflation Reduction Act has also made investors “second guess” their usual investments in oncology, he added.
The $60 million Nexo raised in its Series A round will help them identify at least one drug candidate, the company said. “By the time Nexo needs to raise more capital, the pendulum may have come back a bit,” Rizzuto said.