Has it happened to you yet?
You woke up one morning and something hurt. Not because you finished a marathon the day before and just HAD TO slap another "26.2" sticker on the back of your car. You're better than me. Thanks for the reminder while I'm stuck behind you in traffic. Not because you spent the weekend helping your buddy move for the fourth time in four years. But because you slept wrong. You are now a person who sustained an injury in bed. Welcome to the club.
"I'm getting too old for this." You thought to yourself. Even worse — you said it aloud.
The phrases are coming for all of us. Back in my day. When I was younger. I used to be able to. Little white flags your body starts waving around whether you like it or not.
The Fountain of Youth sounds less like a myth and more like a reasonable ask. What if you could actually take something that worked?
Enter Retro Biosciences. Their stated goal — “add 10 years to healthy human lifespan”. And I promise what they’re doing is more effective than whatever they're selling in St. Augustine.
Okay but how
Your body has a natural way of recycling and cleaning its own cells. Autophagy in medical terms — Greek for "self-eating." Your body's garbage disposal, in layman's terms. It's how your body recycles & replaces broken parts and cellular junk.
When you're young, this works beautifully. As you age, the acid chambers inside your cells that do the actual cleaning lose their strength. The disposal slows, the trash piles up, and toxic proteins accumulate in your neurons. Over time, that buildup is one of the core drivers of Alzheimer's.
That's the first thing Retro is trying to fix.
Their drug candidate, RTR242, is a small-molecule pill designed to restore your cells' cleaning function — essentially give your cells' cleaning mechanism a jump-start and return it to factory settings — an iPhone reset for your body. Yo Siri, play "When You Were Young" by The Killers.
And in December 2025, Retro dosed the first human in a Phase 1 clinical trial in Australia.
What else they have cookin'
Retro’s second program is pure banana-land. Retro partnered with OpenAI to build an AI model that redesigned two Nobel Prize-winning proteins used to reverse cellular aging — making them 50x more effective than the originals. That's the power of AI in science — explore more protein combinations than any human scientist could manage in a thousand lifetimes.
The third program is for the friend we all have. Replace your aging blood stem cells with ones that are biologically age zero. Young cells that ripple out and produce fresh blood across your entire system. Some friends — cough cough, Phil and Justin — can shovel candy like an 11-year-old at a birthday party. Candy on tap at their households. But thanks to Retro Biosciences, you can just swap out all your blood cells and start fresh. We're not there yet... but you're probably safe to grab another pack of Skittles from the candy aisle.
The guy who started it
Joe Betts-LaCroix. A D-average high school student who ended up at Harvard, then MIT and Caltech for research. 100+ patents and two companies followed — one that made the world's smallest Windows PC (OQO) and sold to Google, and another that automated animal research with AI (Vium) and sold to Recursion Pharma.
By the time he started Retro, he'd spent years as a Y Combinator partner watching the longevity space from the inside. He looked at the entire longevity science industry and called it "steeped in marketing, not actual science." So he built his own company out of repurposed shipping containers in a San Francisco warehouse.
Not exactly the origin story you'd draw up for the CEO of the most ambitious longevity company on the planet. But then again, nothing about this company is what you'd draw up.
The honest take
The gap between "works in a lab" and "works in a human" is where longevity companies go to die.
RTR242 is in Phase 1 — which tests safety and tolerability, not whether the drug actually works on aging. We don't know yet if it cures anything. Testing has begun and progress is being made — but so has the competition. Altos Labs launched in 2022 with $3 billion from Jeff Bezos, and Life Biosciences entered human trials in 2026.
Betts-LaCroix said it plainly in an interview with the Financial Times: "Right now if someone gets Alzheimer's, it doesn't matter what your resources are. If you're like Joe Biden, or Elon, or whoever — you can write as big a check as you want to anybody, and nobody knows how to cure it."
Retro doesn't know yet either. They're just further along than almost anyone else on this path — and they got there faster than anyone expected.
If they pull this off
Aging isn't one disease. It's a cascade — a slow unraveling that eventually breaks everything at once. If you can interrupt that cascade early enough, you're not just treating Alzheimer's. You're not just addressing heart disease or cancer. You're pushing back the entire timeline.
Ten extra healthy years. A decade more with your kids. A decade more of your mind working the way it should. A decade of actually living instead of being managed by a system built to comfort you, not fix you.
Oasis said it best. Live Forever. Joe Betts-LaCroix is taking that literally — and he's got the receipts. This past Friday, Retro announced the initial close of their next financing round at a $1.8 billion valuation, led by 4P Capital. Three years from first lab to clinical candidate. Fifteen months from indication selection to first human dosed. More milestones coming in 2026 and 2027. A warehouse full of shipping containers and a long runway to prove it.
The Fountain of Youth was never in St. Augustine. Turns out it might be in a pill. A very small, very science-y pill that a person in Australia swallowed for the first time in December 2025.
Go to the field: retro.bio
Want to work out here?
Retro is hiring scientists, computational biologists, and people who want to add 10 years to the human lifespan in Redwood City, California. If you're going to spend your career somewhere, might as well be somewhere trying to give you more of it.
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