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Sep 21, 2023

ArsenalBio Named to Endpoints 11 List as One of the Top Biotechs of 2023

We are proud to announce that Arsenal has been named to the Endpoints 11, one of the 11 top biotechs of 2023. This is an annual honor selected by the editors of Endpoints News for the most promising and ambitious early-stage companies in the biotech industry. This recognition is a true testament to the valuable work that each and everyone one of you contributes everyday. Ken accepted the award in Boston Sept. 20 on behalf of this outstanding team.  Thank you for your passion and commitment to our mission. Congratulations to all. See excerpt of article below.

The Endpoints 11: The biotech startups making the biggest bets with the most exciting science in 2023

Every year, without fail, the Endpoints11 proves to be the most challenging project I face — and definitely remains the most fun. In an industry where ambition and zeal are trademarks of the most exciting biotechs, how do you narrow the list down to 11 of the most worthy new drug developers to hit the scene?

Without doubt the science remains the crucial element. You have to look for an important advance to make your mark in biotech, and that means tracking down cutting-edge labs that have become skilled at
exploring new opportunities. Drug development is extraordinarily expensive, and that means the backers have to offer credibility with a rep for playing out the game.

You can’t have a syndicate of shaky players when you embark on a journey of years. And then there’s the management team: the people betting a big chunk of their lives that they can accomplish something of real importance. By definition, this is a group that still has a lot to prove, and a series of missteps will take you right off the tracks. So that takes you back to the management team, and the quality of the people they can recruit into the company. Staying focused, identifying the small steps that lead to the big finale, is not an easy task.

I hope you enjoy our list and take away some lessons on who and what gets noticed in a tougher industry environment. Everyone’s bar for success and survival has been raised several notches. That makes the Endpoints 11 more important than ever as we offer a shoutout to some of the standouts.

John Carrol
Founding editor
Endpoints News


CEO: Ken Drazan
CMO: Susie Jun
HEADQUARTERS: South San Francisco, CA

Backers: New investors in the $220 million B round last fall included SoftBank Vision Fund 2, Bristol Myers Squibb, Byers Capital, Emerson Collective Investments, Green Sands, Hitachi Ventures, Sixth Street with a group of founding investors involving Parker Institute for Cancer Immunotherapy, Westlake Village BioPartners, the University of California, San Francisco Foundation Investment Company, Euclidean Capital, Waycross Ventures, and Kleiner Perkins.

The scoop: If you want to examine an ambitious scientific mission in pursuit of the holy grail of oncology R&D, it doesn’t get much better than ArsenalBio.

When the first two big pioneers in CAR-T came along at Novartis and Kite, they were able to prove that engineering patients’ T cells to go after blood cancers could create transformational therapies. By the time the approvals came along, the focus in the lab had already jumped to solid tumors, and next-gen companies would take aim at off-the-shelf allogeneic therapies that wouldn’t delay treatment.

Hematological tumors are relatively easy. You get the T cells to the target, they kill tumor cells. Solid tumors are a completely different story — just getting T cells to the tumor isn’t enough. Their defenses have raised issues with cell exhaustion, targets that overlap with normal tissues — raising problems with off-target toxicity. And when you’re working with patients’ cells, you need to find a way that allows for quick, reliable manufacturing.

They use CRISPR to insert a “very large” piece of DNA that gives them “a hard drive of sorts” — adding a series of functional, DNA-based modules that are put into the DNA template that should perform uniformly in cells with trackable results, Jun says.

That in itself — identifying and making the most efficient chop, inserting a big piece of DNA — was an advance they had to work out on their own, she adds, the first challenge in the gamut of challenges to come.
One of those modules they insert is a logic gate for twin targets co-expressed in the tumor alone. Another module encodes short hairpin RNAs, down-regulating expression of RNA in the T cells, modulating T cell functions and adding to the repertoire in overcoming the tumor’s defenses. And the modules have to work concurrently as planned.

Their screening approach gives researchers the chance to review thousands of drug constructs before they put it to the preclinical test, which is now making the leap into the clinic and the supreme test in humans.
Phase I is going to take time, Jun says. It’s a standard dose escalation study, but that’s not quick or easy when you’re using something this complex.

With well over 200 staffers now and major league investors, multidisciplinary research teams have to stay on track. And that’s no easy task either. Success is based on teams, measured by quarters of the year.
“In order to get there we’re going to have to make a series of scientific advances, things that no one has ever done before,” Jun says.

“We didn’t tell them it was impossible,” she says about her research group. “We just told them, ‘Would you be able to come up with something where you could iterate thousands of combinations?’ We give them one-quarter milestones. Can you do this in a quarter? And each quarter they come up with better solutions as we come along and our speed of iteration has come along as well.

“It really is the vision. We have collected a lot of scientific experts across many disciplines. We have synthetic biologists, computation biologists, automation specialists, immunologists, we have cell biologists, we have a bunch of different scientific disciplines that don’t typically work together and don’t typically work in the field of drug development. So we set a vision that we want to cure solid tumors, which is a big, big vision.”

The biotech got started with launch money in a 2019 Series A round of $85 million from the Parker Institute of Cancer Immunotherapy, their close colleagues at Westlake, UCSF and others. Then Arsenal added a $220 million Series B to power forward with contributions from the likes of Bristol Myers Squibb — also a research partner — and SoftBank Vision Fund 2. Add in a research alliance with Genentech and a highly experienced team in pursuit of solid tumors, and you have a leading effort in the field.

To be sure, lots of money, great science and deep-pocket partners are all great to have. But we’ve seen some of this funding team watch Tmunity and Tessa go down in flames after touting grand visions in cell therapy, and success is not guaranteed. But win or lose, it will be fascinating to watch.

— John Carroll