A medical robot usually announces itself. It has a console, articulated arms, a dedicated room and a capital budget large enough to make it a hospital event. Josh DeFonzo’s new machine makes a quieter entrance. Mendaera’s Focalist system is handheld. It pairs live ultrasound with software and an electromechanical guide that helps a clinician establish and maintain a path for a needle or similar instrument. The task sounds modest until you notice how much of care depends on doing it precisely, repeatedly and on time.
That contrast contains the company’s whole argument. Robotics earned its place in complex surgery, but the technology around motors, sensing, imaging and artificial intelligence kept improving. Why should the robot remain confined to major procedures? DeFonzo and co-founder Jason Wilson started Mendaera in 2020 around the possibility that smaller robots could be useful in the long middle of a care journey, where common interventions still lean heavily on hard-won manual skill.
For DeFonzo, this is a second pass at robotics and at least a sixth pass at the work of turning technical possibility into an operating company. He began in health technology in 2003, after studying economics at the University of California, Berkeley. The career that followed became an education in the unglamorous machinery of adoption: sales, product, marketing, operations, reimbursement, clinical needs and the long relay from prototype to routine use.
Five companies before the company
His early work included Medtronic, then a sales-management role at surgical-visualization startup Invuity from 2007 to 2009. At EndoGastric Solutions, he moved through product, marketing and commercial leadership over five years. He joined diagnostics company CareDx in 2014 and became chief commercial officer the following spring. Each stop changed the technology, customer and business model. The repeated job was learning what prevents an invention from becoming part of daily practice.
Auris Health raised the degree of difficulty. DeFonzo led product strategy and operations and later served as chief operating officer while the company built the Monarch robotic platform. Johnson & Johnson acquired Auris in 2019, and DeFonzo became president of J&J’s Robotics & Digital Solutions business. He had seen a medical-robotics company from the inside, through growth and into a large organization.
“Since my first startup in 2007, it’s been a series of trial and error, and continual learning.”Josh DeFonzo, founder Q&A, 2025
Then came an unusual turn. DeFonzo became CEO and a director of Lux Health Tech Acquisition Corp., a publicly listed acquisition vehicle assembled with Lux Capital’s Peter Hébert and a board that included robotics entrepreneur Fred Moll. In an LSI conversation, DeFonzo still described himself as primarily an operator. The investor-side role gave him another view of capital, timing and company quality. Soon, he was back to building.
The repeated lesson: adoption is a stack
Make the robot do less
DeFonzo and Wilson, a systems engineer and former colleague, began from first principles. Their recurring formulation was simple: a useful product needs a real problem, a product needs a workable business, and the business needs a good company underneath it. Before choosing a device, they asked what kind of organization they wanted to build and what meaningful problem that organization could take on.
The early robotics thesis inverted the usual picture. Warehouses and factories use robots for bounded, repetitive jobs. In medicine, robots had often been built for difficult, high-value operations. DeFonzo wondered whether the form factor and assignment could become simpler. A compact system performing one well-defined task might travel across departments and settings more easily than a room-scale platform. Scale would come from prevalence, not from asking one machine to stage an entire operation.
The team focused on ultrasound-guided instrument placement. The work appears across specialties, yet it asks an operator to acquire an image, interpret it, choose a path and execute that path while coordinating two hands. Mendaera’s concept divided the problem into parts that technology could support: ultrasound for the live view, software for planning, and a handheld robotic component to hold the intended trajectory.
A broad platform can become an excuse for vague research. Mendaera went the other way. DeFonzo said the product and clinical-engineering group engaged more than 1,000 healthcare providers. At previous companies, he noted, reaching 100 could count as substantial. Here the number reflected the variety of users and settings. The underlying motions might rhyme, but the room, pace and people differ. The product had to respect both the common denominator and the local reality.
The first hires arrived even earlier than the evidence. DeFonzo recalls that the first six people joined before the company had a napkin sketch. He and Wilson recruited people they had enjoyed working with, including former Auris colleagues, and looked for polymaths: early employees willing to cover several disciplines to a solid level. The vision brought them in. User research gave the vision edges.
“These are procedures that should just work.”Josh DeFonzo, State of MedTech interview, 2024
A focused company, assembled with partners
Mendaera’s system joins several technical fields, but the company resisted the temptation to recreate every one of them. DeFonzo has described the team’s early look at building its own ultrasound. Established ultrasound ventures had absorbed large amounts of capital; Mendaera had raised roughly $2 million at that point and still needed to build a robot. The arithmetic clarified the strategy.
In December 2023, Mendaera announced a commercial agreement with Butterfly Network. Butterfly’s semiconductor-based, whole-body ultrasound platform was compact and programmable, matching a device meant to move across applications. The agreement let Mendaera concentrate on intervention while integrating an imaging technology built by a specialist.
Three months later, Mendaera acquired Avail Medsystems’ telepresence technology. The added layer allowed remote collaboration around a procedure, extending the idea beyond a steady instrument path to access to another person’s expertise. Build the robotic layer. Partner for ultrasound. Acquire connectivity. The choices formed a product architecture and a capital-allocation philosophy at the same time.
The financing followed. Mendaera had announced a $24 million Series A led by Lux Capital in 2023. In September 2024 it closed a $73 million Series B led by Threshold Ventures, with participation from Lux, PFM Health Sciences and Moll. DeFonzo’s network was not incidental. He had worked with Moll and Lux around Auris, and years inside the medtech community had compounded into relationships able to support another long build.
DeFonzo and Wilson form the company around compact robotics for common interventions.
A $24 million round is followed by a commercial agreement with Butterfly Network.
Mendaera acquires Avail’s telepresence assets and raises a $73 million Series B.
The FDA clears the guidance system in July; first reported Focalist procedures follow in September.
The company prepares to move from limited introduction toward broader launch.
From clearance to routine
On July 2, 2025, the FDA found the Mendaera Guidance System substantially equivalent through the 510(k) pathway. The cleared system provides guidance for precise placement of common interventional devices relative to an ultrasound transducer and its image. In September, Mendaera announced the first procedures using Focalist and began a limited U.S. launch in urology, with additional specialties planned.
For a company like Mendaera, clearance is a gate rather than a finish line. The next work looks familiar from DeFonzo’s earlier career: training, customer support, workflow integration, commercial focus and the accumulating evidence that turns a novel device into a trusted habit. The company hired former Auris colleague Eric Davidson as chief commercial officer in January 2025, another example of DeFonzo drawing on a network forged through previous builds.
His public manner fits that repetition. Investors and former colleagues describe curiosity, resilience, loyalty and intense execution. DeFonzo, meanwhile, jokes that modern medtech can require a taste for punishment. He thanks teams by name, talks about relationships as things to build and fortify, and returns often to learning. Even his ambition comes with a governor: Mendaera wants the platform to span many procedures, he says, but it cannot “boil the ocean” by starting them all at once.
That restraint offers a portable lesson. Mendaera’s mission is broad: make difficult, common procedures more accessible and consistent. Its first machine has a narrow physical job. The company did extensive listening, recruited adaptable people and borrowed strength from an ecosystem instead of treating self-sufficiency as virtue. It preserved the large idea by reducing the number of things that had to go right at once.
The surgical robot shrank because the question changed. Instead of asking how much of a complex operation a machine could perform, DeFonzo asked where a small amount of robotic control could remove friction from work already happening every day. After a career spent around ambitious machines and ambitious companies, he arrived at a practical design principle: make the task clear, make the technology fit the room, and let usefulness earn the right to expand.