Digital medicine company Proteus Digital Health has raised an additional $52 million from undisclosed investors following a whopping $120 million raise the company announced just last month. That brings Proteus' latest round of funding -- its seventh -- to $172 million. By our count the company's total known funding is now close to $400 million, which makes it one of the most-funded, private companies in digital health.

When it announced the first part of this round of funding in June, the company attributed the funds to "major new institutional investors based in the United States, Europe and Asia" and said the money would help it continue to commercialize its ingestible sensor system at scale, as well as to continue demonstrating the value of the technology on health outcomes and costs. 

The Proteus digital medicine platform is a medication management and adherence system that includes unique measurement tools, like sensor-enabled pills, a peel-and-stick biometric sensor patch worn on the body, and companion smartphone apps. The patch records when a pill is ingested and also tracks other things like sleep patterns and physical activity levels. The ingestible sensor component secured FDA clearance in July 2012, while the company’s sensor-laden patch got FDA clearance in 2010.

“The information we measure is verifiably accurate and not just consumer-grade or a toy,” Proteus CEO Andrew Thompson told MobiHealthNews in an interview earlier this year. “The second thing we actively build for our customers is the opportunity for our patients and their families to engage in their care… because when you swallow a drug [our system] creates information about what you swallowed and how your body is responding to it — all of that is then going to be [displayed] on your mobile phone.”

In March the company announced this past March that it would open its first international manufacturing plant for its digital medicine system in the UK, in partnership with parts of the UK's National Health Service. The company said it expected to employ 200 at the facility.

While June's $120 million raise already earned Proteus this title, the total $172 million round makes for the largest single funding raise in 2014 or 2013. In January Proteus raised $32 million in debt financing, but the company's last equity raise was a $45 million round reported a year ago. That round was led by Oracle with participation from existing investors Otsuka, Novartis, Sino Portfolio and others. Proteus also lists Medtronic, Kaiser Permanente, Carlyle, Essex Woodlands, and ON Semiconductor as investors.