Arda Therapeutics doesn't quiet disease. It deletes it.

A 21-person lab betting that disease has an address

Walk into Arda Therapeutics today and you find a small team in San Carlos staring at maps. Not maps of streets, but maps of cells - millions of them, sorted, labeled, and color-coded by single-cell sequencing. Somewhere in those maps is a population of cells that shouldn't be there. Arda's entire reason for existing is to find that population, mark it, and design a biologic that removes it. Nothing more. Nothing less.

It is a deceptively simple pitch for a field that loves complexity. Pharma has spent decades building drugs that dial proteins up or down, often for life, often with side effects, rarely with a cure. Arda thinks that whole approach treats the smoke and ignores the fire. The fire, in their telling, is the cell itself.

When the cause is a cell, why drug the protein?

Chronic disease is stubborn for a reason. In fibrosis, a fraction of misbehaving cells lay down scar tissue until an organ stiffens and fails. In autoimmune disease, a rogue cell population attacks healthy tissue. In metabolic disease, certain cells tip the body's chemistry out of balance. The conventional answer is to block one of the many proteins these cells secrete - a strategy that is a bit like unplugging one speaker at a very loud concert.

The cells keep playing. They keep producing dozens of other proteins, finding workarounds, adapting. Patients stay on the drug indefinitely, managing rather than resolving. Arda's founders looked at that loop and saw an obvious, uncomfortable shortcut: stop chasing the proteins and remove the source.

The trouble, historically, was precision. You can't just delete cells indiscriminately - healthy tissue gets caught in the blast. What changed is the data. Single-cell sequencing now lets researchers catalog every cell in a tissue and spot the pathogenic subpopulation by its unique surface markers. The address became findable. That's the opening Arda walked through.

From aging research to cell deletion

Adam Freund did not arrive at this idea by accident. Before Arda, he was a Principal Investigator at Calico Life Sciences, Alphabet's secretive longevity venture, where he initiated and led the company's most advanced anti-aging therapeutic program - a first-in-class biologic aimed at a validated aging pathway. He watched Calico grow from 15 people to more than 200. His training is an unusual hybrid: a Materials Science degree from Stanford and a Ph.D. in Molecular and Cell Biology from UC Berkeley. Hardware instincts, applied to biology.

He co-founded Arda in 2021 with Rémi Laberge, who serves as CTO. Their bet borrows shamelessly from oncology, which is the one field that already knows how to kill a specific kind of cell on purpose. Chemotherapy and CAR-T cells were built to eliminate cancer cells. Arda's question was simply: why stop at cancer? If you can target and deplete a tumor cell, the same logic should apply to a fibrotic cell, or an autoimmune one.

Investors agreed. In October 2024, Arda closed a $43 million Series A led by Andreessen Horowitz's a16z Bio + Health, with Two Sigma Ventures, Eli Lilly, GV, and a long roster of others joining. Around the same time, the company brought on Scott Turner - formerly chief scientific officer at Pliant Therapeutics, where he built the fibrosis discovery platform - as its CSO.

Find the cell. Mark the cell. Remove the cell.

Arda's machine has two halves. The first is a discovery engine that ingests single-cell data from patient tissue and uses computation and machine learning to identify which cells are driving disease - and, critically, what surface markers distinguish them from their healthy neighbors. The second half turns those markers into precision biologics that bind only the harmful cells and deplete them, leaving the rest of the tissue alone.

The initial targets are chronic conditions where a small, identifiable cell population does outsized damage: pulmonary and other fibrotic diseases, autoimmune disorders, and metabolic disease. Because the underlying technique is platform-shaped, the same engine can in principle point at many diseases - the limiting factor is data, not chemistry.

The receipts, so far

Arda is young, and honest observers should note it is pre-commercial - the proof here is in capital, talent, and conviction rather than approved drugs. But that proof is not trivial. When a16z Bio + Health leads your round and Eli Lilly writes a check, it signals that serious money believes the cell-depletion thesis is more than a clever slide.

The full cap table is a who's-who

Treating disease by subtraction

Strip away the platform language and Arda's mission is almost philosophical. Modern medicine is largely additive: add a molecule, block a pathway, supplement a deficiency, repeat forever. Arda proposes the opposite - that the most durable way to treat certain diseases is to take something away. Remove the cells at the root, and the cascade of proteins they produce simply stops.

There's a longer horizon too. Freund's background is in aging, and Arda's framing extends naturally from chronic disease into age-related deterioration, where the slow accumulation of dysfunctional cells is a recurring villain. The company is careful not to over-promise on the aging front. But the throughline is clear: if disease has a cellular address, you can evict the tenant.

A different kind of cure

If Arda is right, the implications stack up fast. A fibrosis patient might receive a course of treatment that removes the scar-forming cells rather than a daily drug that slows them. An autoimmune patient might have the offending cell population cleared instead of broadly suppressing their immune system. The dream is fewer chronic prescriptions and more actual resolutions.

If Arda is wrong, it will be for the reasons biology is always humbling: pathogenic cells may be harder to isolate than the data suggests, or depleting them may have consequences nobody predicted. That's the honest risk in any platform this early. The skeptic's caution is warranted, and Arda's own leadership frames the work as a bet, not a sure thing.

Now go back to that small team in San Carlos, still staring at their cellular maps. The difference is that the maps are no longer just pictures - they're targets. Where medicine once saw a fog of proteins to manage, Arda sees a specific cell with a specific address, and a biologic on the way to its door. They haven't cured anything yet. But they've changed the question from "how do we manage this?" to "which cells do we remove?" - and in a field allergic to simple questions, that alone is worth watching.