Ben Casavant and the Long Trip Between a Patient and an Answer

The patient had a number, as research patients often do. Patient No. 45 lived in rural Wisconsin, hours from the clinic where Ben Casavant was doing doctoral work with an oncologist. The researchers saw a change in the patient's markers and asked him to return for bloodwork. He chose to wait until his next scheduled appointment. The drive was simply too much.

He never made that appointment. Years later, Casavant could still summon the number immediately. The memory supplied more than sadness; it gave shape to an engineering question. Modern diagnostics could measure extraordinary things, but first a person and a needle had to occupy the same room. For anyone far from a clinic, short on time, wary of needles, or enrolled in a study requiring repeated samples, the front door to the laboratory was oddly narrow.

“Patient No. 45; I’ll never forget that. He didn’t make it to that next appointment.”Ben Casavant, University of Wisconsin-Madison, 2024

Casavant's answer became Tasso, the Seattle company he started with fellow biomedical-engineering doctoral student Erwin Berthier. The name means “badger” in Italian, a compact tribute to their University of Wisconsin roots. Their device attaches to the upper arm. Pressing a button deploys a lancet for less than a second and creates a slight vacuum; blood flows into an attached collection tube. The sample can then go to a laboratory. The drama of the needle has been compressed into a button and a return package.

A laboratory generous enough for failure

Casavant arrived at Wisconsin after earning a bioengineering degree from the University of California, Berkeley in 2009. He joined Professor David Beebe's lab, where work on microfluidics allowed fluids to be guided through small channels with unusual precision. Casavant later said Beebe took a chance on him when his resume was not the strongest. More important, the professor gave him space to be creative, to try things, and to fail with cover.

That is a useful education for a medical-device founder. Biology is unmoved by a handsome prototype. Regulators do not grade on charm. A self-collection device has to be understandable to someone who has never seen it, reproducible on a manufacturing line, compatible with laboratory methods, safe in the hand, and reliable after shipping. Tasso's path ran through more than 20 iterations. Casavant has described the company's progress with a line that sounds perverse until one thinks like an engineer: “We failed at every single step and that’s exactly why we succeeded.”

The device is therefore only the visible portion of the work. Tasso built kits and logistics around it because a convenient collection that arrives unusable is merely a better designed disappointment. Liquid and dried samples suit different laboratory workflows. Room-temperature stability can matter. So can a prepaid box, clear instructions, and the quiet confidence that an ordinary person can complete the process without a phlebotomist standing nearby.

Grants first, scale later

Casavant and Berthier began the company while their academic work was still close at hand. The early years were financed less like a fashionable consumer startup than a patient science project. Federal support from agencies including DARPA, the Defense Threat Reduction Agency and the National Institutes of Health helped develop the core technology. A 2014 small-business award named Casavant as principal investigator on work toward a self-administered collection and sample-preparation device.

Venture money followed evidence. Tasso announced a $17 million Series A in 2020, as the pandemic made the inconvenience of clinic-bound testing newly obvious. In December 2021 came a $100 million Series B led by RA Capital Management. The company said that round brought its funding total to $131 million and would expand manufacturing, operations and remote-testing services. Capital is a poor substitute for clearance, however, and the next milestone was the sort printed in regulatory prose.

The FDA's decision record says Tasso+ was found substantially equivalent in August 2022. European certifications followed, along with Health Canada licensing for a later device and a Japanese joint venture. Each approval enlarged the addressable map. It also tested whether the original promise could survive translation across rules, laboratories and health systems.

Casavant has kept one foot in the technical record while running the company. Tasso credits him with more than 27 publications and 25 patent applications. His graduate work included papers on suspended microfluidics and rare-cell analysis, subjects with titles far removed from the simplicity of a button on an arm. In 2024, Wisconsin's College of Engineering gave him an Early Career Award. PharmaVoice included him among its clinical-trial professionals the same year. The recognitions arrived after the long middle of company building, when the interesting scientific question had to become a repeatable object, and the repeatable object had to become an organization capable of making, documenting and shipping it.

“In order to change the industry, leaders need to be persistent in the face of challenges and navigate entrenched systems.”Ben Casavant, PharmaVoice, 2024

The people who are missing from the waiting room

Remote collection changes more than convenience. It changes who can realistically participate. A clinical trial may ask for repeated samples at precise intervals. A genetics study may need people who live nowhere near a major research center. Traditional collection quietly favors those who can travel, take time away from work, arrange care, and tolerate another appointment. The bias looks logistical, which is perhaps why it can pass unnoticed.

Casavant has made geographic reach part of the argument. In a 2024 conversation about the Parkinson's Foundation's PD GENEration study, he said diversity of location was important because remote areas may have limited access to phlebotomists. Participants could receive a kit, collect with online guidance, and mail the sample for analysis. By March 2026, the foundation and Tasso said the wider study had enrolled more than 30,000 people.

The same underlying system has appeared in less obvious settings. Tasso technology has supported research and decentralized trials, and collection programs associated with Major League Baseball and the Olympics. In February 2026, Tasso and InnoVero announced that their system would be deployed for anti-doping collection at the Winter Games. Different rooms, different rules, same engineering concern: how to get a trustworthy sample without making the collection itself the event.

Casavant's public manner contains a useful contrast. He talks in the language of regulatory pathways and laboratory compatibility, yet he does not appear eager to behave like a solemn monument to biomedical engineering. Asked whether he preferred winter or summer in Madison, he answered, “Dude, does anyone say winter?” He sailed with the Hoofers club, chooses the Memorial Union Terrace over Lake Mendota when forced to pick, and searches ice cream shops for orange custard chocolate chip. He says nobody makes it as well as Babcock Dairy. The quest, so far, has produced disappointment.

That lightness coexists with an unusually long horizon. At Tasso, a decade of development preceded the period of large funding rounds and broad regulatory reach. Casavant says he enjoys building alongside people and watching change happen. He credits Beebe not only for admission to a lab but for the freedom to fail inside it. The pattern repeats: people make room, experiments misbehave, the work improves.

A sentence worth making boring

Casavant's aspiration is best understood as a line of dialogue. He wants a doctor to be able to say, “You can do the blood draw or we can just send you a Tasso.” The sentence is casual by design. If it becomes unremarkable, the company will have helped turn an elaborate chain of engineering, manufacturing, regulation and logistics into an everyday choice.

He imagines the next step as more than isolated convenience. Samples collected over time could build a longitudinal record, making patterns easier to see and decisions possible earlier. The ambition depends on doing the prosaic things well: the button, the tube, the label, the package, the handoff, the laboratory. Healthcare has no shortage of dazzling back ends. Casavant chose to work on the front door.

Patient No. 45 remains at the beginning of that choice. The story is not an argument that distance is the only barrier, or that a mailed kit can dissolve every inequity. It is a reminder that systems teach people what they are expected to endure. For a long time, the blood draw stayed put and the patient did the traveling. Casavant looked at that arrangement and decided the smaller object should move.