
Just shy of its 1-year anniversary, radiopharmaceuticals platform play RayzeBio bags another megaround
Perhaps they should have called it RaiseBio.
Not even a full year post-launch, RayzeBio’s radiopharmaceuticals platform has hooked yet another $100 million-plus raise, and it appears the company’s next big catch will be a Nasdaq ticker.
CEO Ken Song unveiled the Series C round Tuesday morning, bringing the fledgling biotech’s total raise to $258 million. While he was hesitant to call it a crossover round, he said it very well could be RayzeBio’s last private round of financing.
“We’re open to looking at all things, but there’s no immediate plans to take the company public, particularly since we’re so well capitalized at this time,” he told Endpoints News.
RayzeBio was established back in August 2020, and launched a couple months later with seven radiopharmaceuticals programs. Unlike radiation therapy, which is administered by an external beam of high-energy rays, radiopharmaceuticals deliver radioisotopes to tumors via the bloodstream.
The overall concept is similar to that of an antibody-drug conjugate, Song said — it all starts with a binder, a linker and a payload. Except instead of an antibody, RayzeBio is deploying smaller peptides, and instead of a chemotherapeutic payload, there’s a radioactive particle which is “many orders of magnitude” more potent.
From the beginning, RayzeBio established a partnership with Japan’s PeptiDream to discover new peptides against a range of validated solid tumor targets. The peptides are then radiolabeled with the company’s preferred radioisotope, Actinium-225. But RayzeBio is also exploring the use of other radioisotopes, and additional approaches to identify binders — and as a result, the team has expanded beyond its initial seven programs.
Song plans on using the Series C funds to bring more than one candidate into the clinic, though he declined to comment on a timeline.
“We’re still very much focused on advancing a pretty broad pipeline of programs, and we’ll be able to provide an update hopefully in the near future, as towards timing into the clinic,” he said.
Since December, the team has grown from 13 to more than 30, not counting contract workers. That includes Eric Bischoff, a colleague from Song’s Metacrine days, who’s now SVP of development and operations. Gary Li, head of biology and translational medicine, was formerly SVP of translational medicine at QED Therapeutics. Head of discovery Derek Cole hails from Takeda, where he led medicinal chemistry for the GI-drug discovery unit. They all joined Deborah Charych, who co-founded RayzeBio and is now CTO.
The company came together around a “convergence of interests,” Song said. There’s been increasing interest in radiopharmaceuticals over the last decade, with notable entrants like Novartis, which snagged FDA-approved Lutathera and PSMA-617 from a $3.9 billion acquisition of Advanced Accelerator Applications.
“There’s actually a fair number of smaller radiopharmaceutical companies that are out there,” Song said. “But I would say that RayzeBio is unique in the breadth of our pipeline, as well as our selection of targets that we’re pursuing would largely be viewed as first-in-class within the radiopharmaceutical sector.”
Back in December, the company said it would use part of a $105 million Series B round to fund studies into manufacturing options. Making radioisotope-drug conjugates requires a bit more specialization than typical therapies. While the company is currently doing some radiolabeling in-house, it’s mostly for research purposes, Song said.
“When it comes to actual manufacturing and distribution, we’re likely to work with contract manufacturers to begin with and then evaluate whether or not there’s any need to invest in any of our own infrastructure,” Song said.
The Series C was led by Venrock Healthcare Capital Partners, with some help from a slate of new and old investors, including Perceptive Advisors, Vivo Capital, Acuta Capital Partners, Deerfield Management, TCG X, venBio Partners, Versant Ventures, Samsara BioCapital, Redmile Group, Viking Global Investors, Cormorant Asset Management, OrbiMed, LifeSci Venture Partners, Logos Capital, Alexandria Venture Investments, and others.
“Our goal is to build the leading radiopharmaceutical biotechnology company that is able to take products from initial concept all the way through to delivery to patients, and be a free standing enterprise,” he added.