“This is a massive win for Boston,” said Ryan Durkin, a vice president of Whoop who works on AI at the maker of health-tracking wristbands. PathAI and Whoop belong to the recently formed Massachusetts AI Coalition, a group of more than a dozen local tech companies seeking to spur AI growth here. “Andy Beck walked away from a tenure-track position at Harvard Medical School in 2016 to start PathAI right here. He didn’t go west. He bet on Boston.”

Beck, 45, is a former researcher at Beth Israel Deaconess Medical Center and one-time associate professor of pathology at Harvard Medical School.

While the Boston area has a long history of AI-related deals, it has seen only a few acquisitions of more recent generative AI companies, according to data from research firm PitchBook. Last year, the AI e-commerce startup OfferFit fetched $325 million from Braze, the New York online marketing firm, and the video AI firm Goldcast was bought by the events tech company Cvent for almost $300 million, according to Axios.

PathAI straddles medicine and tech. Beck, who completed his residency and fellowship at Stanford University School of Medicine and earned a PhD in biomedical informatics there, says his company’s software can transform how pathologists analyze body tissue to diagnose cancer and other diseases.

Since the 1800s, doctors have taken thin slices of biopsied tissue stained to highlight cell structures, placed them on glass slides, and studied them under a microscope. While this practice remains the gold standard, it leaves findings open to interpretation and raises the possibility that a pathologist may miss cancer. It also limits the ability of doctors to easily share tissue samples to confirm diagnoses.

PathAI developed software that digitizes the slides and uses AI to analyze them at the most granular level. Sitting at a conference table at PathAI while sipping a glass of iced coffee, Beck opened his laptop and showed high-resolution pink and orange images of cancerous lung tissue. Tapping on the computer, he used AI to instantly calculate the exact number of cancer cells in the tissue sample: 13,540.PathAI scientists repeatedly corroborated the accuracy of such calculations while working on the software, Beck said.

Not only does the software analyze tissue far more thoroughly than a pathologist could with a microscope, but Beck also said, it may help doctors pinpoint which drugs might be most effective in treating the disease.

“We think in the future every slide will be digital, and every interpretation will be assisted by AI,” said Beck, PathAI’s chief executive. “That will be a big change from the way pathology is practiced today.”

Nonetheless, he said AI will augment what pathologists do, not replace them. Pathologists will still be needed to interpret digital diagnoses and to advise clinicians who are treating patients. “AI is a tool that makes them better at it,” he said.

Roche, a leading maker of cancer drugs, liked PathAI’s software so much, it wanted the startup.The pharmaceutical company plans to pay $750 million upfront, with PathAI eligible to receive an additional $300 million if the deal achieves certain milestones. The acquisition is expected to close in the second half of the year, and PathAI, which has about 200 employees, will become part of Roche’s diagnostics division.

“Digital pathology has the potential to improve precision diagnosis of cancer and enable physicians to offer better-tailored treatment regimens,” Matt Sause, chief executive of Roche’s diagnostic division, said when the deal was announced.

PathAI had raised $255 million in venture capital to date.

The deal builds on a five-year partnership between the two companies. The partnership expanded in 2024 to include the development of AI-powered “companion diagnostic algorithms,” which would pinpoint patients who might benefit from a particular drug.

“It was clear from the beginning in my mind that they were a likely acquirer,” Ronald Paulus, a board member of PathAI who helped lead negotiations with Roche, said of the pharmaceutical company. “The synergy was so overwhelming.”

Beck said PathAI’s relationship with Roche grew closer after he and several high-ranking executives at the startup visited the pharmaceutical company’s chief executive, Thomas Schinecker, and Sause in Switzerland the past two summers.

The agreement was welcome news in the AI world of Massachusetts. With AI startups attracting two-thirds of all US venture capital funding last year, entrepreneurs have seen the state’s share of VC dollars shrinking.

To be sure, there have been some bright spots. In addition to the acquisitions of OfferFit and Goldcast, several Massachusetts-based AI companies have attracted hundreds of millions of dollars in venture capital in recent years, including autonomous software developer Blitzy, AI music generator Suno, and AI model developer Liquid AI. In March, Whoop announced the largest venture capital deal of the year for local startups up to that point, a $575 million haul from investors that included the Mayo Clinic.

If there is a lesson to be learned from the PathAI acquisition, experts say, it’s that Massachusetts AI companies excel when they harness their technology to make advances in other fields. That’s a sharp contrast with the bigger, more general-purpose AI companies in Silicon Valley, such as OpenAI, Google, Elon Musk’s X.ai, and Anthropic.

In Massachusetts, AI companies have to “combine the technology with the way a service is delivered,” said Caitlin Donovan, a partner at the Cambridge-based venture capital firm General Catalyst, which owns about 10 percent of PathAI. “PathAI is such a prime example of how that works.”

Eric Paley, the Massachusetts secretary of economic development, agreed. He said that the most promising AI companies in the state are “AI plus” something else, ranging from health care to music.

“We are really focused on using these technologies in ways that change how industries work,” he said. “You’re going to see this ‘applied AI’ being a core driver of a whole new wave of companies.”

Aaron Pressman of the Globe staff contributed reporting.

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Jonathan Saltzman can be reached at jonathan.saltzman@globe.com.