A 13-person biotech that decided to drug one of cancer biology's hardest targets - the Hippo-YAP pathway - and, against the odds, got a molecule into patients who had run out of options.
Here is a thing about drug discovery that sounds made up but isn't: for years, some of the most important cancer biology known to science was considered essentially undruggable, and the polite thing to do in a pitch meeting was to nod, acknowledge the elegance of the target, and then go work on something else. The Hippo-YAP pathway was one of those targets. It governs how cells decide to grow, divide, migrate, and die - which is exactly why, when it breaks, cancer tends to follow. Lung, gastric, colon, cervical, ovarian, breast, liver, melanoma. The pathway is everywhere. It is also, structurally, a nightmare to hit with a small molecule.
Vivace Therapeutics is the company that decided to hit it anyway.
Founded in 2015 by Sofie Qiao - who had come from WuXi Ventures, the corporate venture arm of the contract-research giant WuXi AppTec - Vivace was built around a specific, slightly nerdy insight. Rather than trying to pry apart the sprawling YAP-TEAD protein interaction directly, the company went after a fatty-acid modification called palmitoylation. TEAD proteins, it turns out, quietly attach a lipid tag to themselves - auto-palmitoylation - and that tag is load-bearing. Block it, and the whole YAP-TEAD transcriptional machine grinds down. It's the kind of mechanism that reads like a footnote in a cell-biology paper until someone realizes it might be a door.
The structural bet came bundled with a business bet, and the business bet was arguably just as unusual. Vivace was designed as a capital-efficient "virtual biotech" running an East-West model: WuXi would serve as the research engine in the East, while a lean, experienced management team steered development from the U.S. This is the sort of org-chart innovation that doesn't make headlines but quietly decides whether a company lives long enough to matter. With roughly 13 employees, Vivace would eventually run a clinical program spanning more than 200 patients - a ratio that would make most large pharma operations blink.
The lead candidate is VT3989, a first-in-class small molecule and, by Vivace's account, the first and only member of the TEAD auto-palmitoylation inhibitor class for which compelling clinical efficacy data have been publicly reported. The mechanism, simplified, looks like this:
TEAD proteins attach a lipid via auto-palmitoylation - a switch the cancer relies on.
The small molecule inhibits that palmitoylation, disarming TEAD.
Without functional TEAD, the YAP-TEAD transcription program shuts down.
Especially in mesothelioma and NF2-mutant tumors that lean on this pathway.
The results that got people's attention came in patients with malignant mesothelioma - a brutal, asbestos-linked cancer with few good options - who had already failed chemotherapy and immuno-oncology combinations. In that setting, VT3989 posted roughly a 32% objective response rate, with responses that were durable and, importantly, a tolerability profile that stayed clean. In 2023, at the American Association for Cancer Research annual meeting, Vivace reported what it described as the first clinical proof-of-concept for a cancer drug targeting the Hippo-YAP pathway. That is the kind of sentence a company spends a decade earning the right to say.
Vivace has raised approximately $105 million since 2015 - a deliberately lean number for a company that ran a 200-patient clinical program. Capital efficiency wasn't a constraint here so much as the entire strategy.
Backers across the rounds include Canaan Partners, WuXi Healthcare Ventures, Cenova Capital, Sequoia Capital China, Mission Bay Capital, and - leading the 2025 Series D - RA Capital Management, whose partner Jake Simson joined the board.
First-in-class small-molecule YAP/TEAD inhibitor blocking TEAD auto-palmitoylation. Evaluated in 200+ patients with durable responses in refractory mesothelioma and NF2-mutant tumors. FDA Orphan Drug Designation granted for mesothelioma in 2025.
Additional small-molecule programs targeting the Hippo-YAP pathway, with potential reach across multiple solid tumors - and possible non-oncology uses such as fibrotic disease, where the same pathway is implicated.
An industry-leading understanding of Hippo-YAP biology, drug-resistance mechanisms, and biomarker-driven patient selection - the durable asset underneath the individual molecules.
Founded Vivace in 2015 after leading WuXi Ventures. Architect of the company's East-West virtual-biotech model. Served on the board of the Biotechnology Innovation Organization (BIO), 2020–2024.
Leads the company's clinical and corporate strategy as it steers VT3989 toward a registrational Phase 3 program.
Oversees clinical development of VT3989 across mesothelioma and NF2-mutant solid tumors.
Leads business development and corporate strategy for the pipeline.
Sofie Qiao co-founds the company with a $15M Series A from Canaan Partners and WuXi Healthcare Ventures, built around novel Hippo-YAP pathway IP.
A $25M Series B brings total early funding to $40M as Vivace emerges publicly.
Fresh capital pushes the lead Hippo-pathway program toward the clinic.
Vivace begins dosing patients with VT3989 in its first-in-class TEAD inhibitor study.
The first publicly disclosed clinical proof-of-concept for a Hippo-YAP-targeting cancer drug.
A $35M Series D led by RA Capital and FDA Orphan Drug Designation for VT3989 set up a planned registrational Phase 3.
It is a clinical-stage oncology company developing first-in-class small-molecule drugs that target the Hippo-YAP signaling pathway, led by its YAP/TEAD inhibitor VT3989.
VT3989 is Vivace's lead drug candidate - a first-in-class small molecule that inhibits auto-palmitoylation of TEAD proteins, blocking the YAP-TEAD transcriptional activity that drives certain cancers, notably mesothelioma and NF2-mutant tumors.
Vivace was founded in 2015 by Sofie Qiao, Ph.D., previously of WuXi Ventures. It is led as President & CEO by Craig Gibbs, with Neelesh Sharma, M.D., Ph.D., as Chief Medical Officer.
Approximately $105 million across four rounds, most recently a $35 million Series D in March 2025 led by RA Capital Management.
It is headquartered at 1510 Fashion Island Blvd, San Mateo, California, in the San Francisco Bay Area.
Video: search "VT3989 AACR" or "Vivace Therapeutics" on YouTube for conference presentations and mechanism explainers. No official product-demo video is published by the company at this time.