The Sage Vets Who Raised $106M to Take Another Swing at the Brain

Shopping Spree in Tokyo and Shanghai

What makes Tortugas unusual: it didn't start in a lab. It started with a shopping list.

Instead of spending years on early discovery, the company in-licensed four clinical-stage drugs from two established pharma partners. Two came from Hansoh Pharmaceutical (based in Greater China) and two from Eisai (based in Japan). All four are small-molecule pills designed for once-daily dosing, which matters a lot when you're treating chronic brain conditions. Nobody wants to wrestle with a complicated dosing schedule on top of schizophrenia.

Think of it like buying a house that already has the foundation and framing done, rather than starting from a pile of lumber. The drugs have already been through early human testing, so Tortugas can skip straight to Phase 2 trials (the mid-stage studies that test whether a drug actually works in patients).

The Hansoh assets include a schizophrenia drug that combines two validated mechanisms (targeting dopamine D2/D3 receptors and serotonin 5-HT2A) into a single molecule, plus a tinnitus treatment that works on GABA receptors in the brain. That tinnitus program is especially interesting because there are currently zero FDA-approved drugs for the condition. If you have chronic ringing in your ears, your doctor is essentially improvising with off-label medications.

From Eisai, Tortugas picked up a focal epilepsy drug (targeting a protein called GAT-1 that regulates the brain's main inhibitory chemical) and a treatment for reversible encephalopathies (a group of conditions where the brain temporarily swells or malfunctions). A fifth, discovery-stage program remains undisclosed.

Why Now? Because the Ice Is Thawing.

For years, brain drugs were the place where pharmaceutical dollars went to die. The biology was too complex, the clinical trials too expensive, and the failure rates too punishing. Big pharma quietly tiptoed out of CNS research throughout the 2010s, leaving a gap that only the bravest (or most stubborn) biotechs tried to fill.

But the mood has shifted. The broader CNS therapeutics market, valued at roughly $128 billion in 2025, is projected to reach $221 billion by 2035. Johnson & Johnson made the sector's biggest statement of confidence last year when it acquired Intra-Cellular Therapies for $14.6 billion. New technologies for getting drugs past the blood-brain barrier (the biological bouncer that keeps most medicines out of your head) and AI-powered drug discovery tools are making investors feel less like they're throwing money into a black hole.

Tortugas is riding that wave, but with a notably old-school approach. No gene therapy. No AI platform. No fancy modality. Just oral pills targeting well-understood brain pathways, developed by people who've done it before. In a sector that loves shiny new platforms, there's something refreshingly pragmatic about the strategy.

The $106 Million Question

The money will fund completion of Phase 2 trials for the two lead programs (schizophrenia and tinnitus), which means we should see clinical data within the next couple of years. That's the real test. Validated mechanisms and experienced leadership get you funded, but only data gets you to the finish line.

And the risks are real. That 85% failure rate in CNS trials isn't just a scary statistic; it reflects genuinely hard biology. One of Eisai's assets (the PDE9 inhibitor for encephalopathies) may share a lineage with a compound that previously disappointed in dementia trials, though Tortugas hasn't confirmed that connection. Even the schizophrenia space, despite using "validated" drug targets, is littered with programs that looked promising on paper and then crumbled in larger studies.

Still, there's a compelling logic to what Jonas and Robichaud are building. They're not betting on one drug or one indication. They've assembled a diversified portfolio of four clinical-stage assets across four different conditions, all with long patent life and room for expansion into additional uses. If even one or two of these programs hit, the $106 million looks like a bargain.

The CNS graveyard is very real. But every now and then, someone walks through it and finds something worth digging up. Tortugas is betting that a couple of Sage veterans, armed with Japanese and Chinese chemistry and a war chest of venture capital, are exactly the right people to do the digging.

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