Sonde

A voice-based artificial intelligence platform to detect changes in health

< FOUNDED ENTITIES

A voice-based artificial intelligence platform to detect changes in health

34.8% Equity

COMMERCIAL RELEASE

Description

A voice-based artificial intelligence platform to detect changes in health

Puretech Ownership¹

34.8% Equity

Stage of Development

COMMERCIAL RELEASE

¹ As of December 31, 2024, PureTech’s percentage ownership of Sonde was approximately 34.8% on a partially diluted basis. This calculation includes outstanding shares, options, and warrants, but excludes unallocated shares authorized to be issued pursuant to equity incentive plans.

A voice-based artificial intelligence platform to detect changes in health

Sonde is developing a voice-based technology platform that detects changes in the sound of voice that are linked to health conditions – like depression, anxiety and respiratory disease – to provide health tracking and monitoring. Sonde’s proprietary technology can be integrated into ubiquitous devices such as smartphones, headphone and smart speakers.

Program Discovery Process by the PureTech Team
- We identified vocal features as a leading non-invasive source of health data, particularly given the evolving technology landscape where voice interactions with devices are rapidly increasing and in-licensed proprietary technology from Thomas Quatieri, Ph.D., at MIT’s Lincoln Laboratory in May 2016. We developed additional, novel intellectual property around this concept and helped advance the technology from an academic concept to a commercially focused technology.
Milestones Achieved & Developmental Status
- In the February 2025, Sonde began design and implementation of validation studies with three organizations within the Department of the Air Force (DAF). Two organizations will be studying the impact of shift work on soldiers’ performance beginning in March and the third organization will study the impact of fatigue on soldiers operating in the field beginning in June.
- In the February 2025, Sonde successfully completed a large-scale trial with one of the top oil and gas conglomerates in the world. Over 4,000 workers used Sonde’s Mental Fitness tracking app and insight dashboard over 5 weeks at 60 different sites. Sonde was able to effectively identify at-risk workers, enabling proactive intervention by flagging individuals with high sensitivity and deliver significant positive predictive value for a healthy population, ensuring most workers who needed support were identified.
- In the January 2025, Sonde successfully integrated its voice-based health monitoring technology into Qualcomm’s Snapdragon® S7+ Gen 1 Sound Platform. Building on its longtime partnership with Qualcomm, Sonde optimized its technology to operate within the strict power and processing constraints of audio earbud and headset devices while maintaining its industry- leading accuracy.
- In August 2024, Sonde announced that it has been selected by AFWERX, the innovation arm of the Department of the Air Force (DAF), for a Small Business Innovation Research (SBIR) Phase II contract in the amount of $1,215,606 focused on Sonde Mental Fitness. This contract builds on work completed through a Phase 1 contract awarded in January 2024 that identified multiple use cases for employing Sonde Mental Fitness vocal biomarker tracking to promote mental health engagement and resource utilization and to enhance operational decision-making. The customization and integration work planned for this SBIR Phase II effort will enable use and validation of Sonde’s mental fitness tracking technology in DAF settings.
- In July 2024, Sonde launched Sonde Cognitive Fitness, which analyzes eight vocal characteristics from 30-second voice interactions to provide insight into one’s cognitive state, helping people manage their mental well-being and productivity effectively.
- In March 2024, Sonde announced the publication of a new study that has validated the ability of the company’s mental fitness vocal biomarker (MFVB) platform to reliably distinguish individuals with elevated mental health symptoms. The four-week cohort study revealed a statistically significant correlation between voice-based identification of increased or decreased mental health risk with the results of the M3 Checklist, a clinically validated mental health assessment. The research, published in the peer-reviewed journal Frontiers in Psychiatry, highlights the potential of vocal biomarkers and Sonde’s technology specifically to provide objective data that can complement clinical care and improve self-monitoring for conditions like depression, stress- and trauma-related conditions, and anxiety.
- In May 2023, Sonde announced the publication of new research that demonstrates the ability of its respiratory responsive vocal biomarker (RRVB) machine learning model to differentiate patients with COVID-19 from healthy individuals with about 70% accuracy. The peer-reviewed study, which was published in the Journal of Medical Internet Research, suggests the RRVB tool could serve as a pre-screening tool for acute respiratory infection and pave the way for the development of voice-based tools for future disease detection and monitoring applications.
- In February 2023, Sonde and the Massachusetts General Hospital Frontotemporal Disorders Unit announced they had been selected by the Massachusetts Artificial Intelligence and Technology Center for Connected Care in Aging & Alzheimer’s Disease (MassAITC) to lead a pilot study focused on leveraging vocal biomarkers for remote detection and monitoring of mild cognitive impairment in the home environment. Funded by MassAITC and the National Institute on Aging, a division of the U.S. National Institutes of Health, the project is part of a $1.7 million grant to explore the use of artificial intelligence and other advanced technologies for in-home care. Specifically, it will evaluate the feasibility of obtaining voice recordings of older individuals in the home environment that can be used to longitudinally monitor speech and memory functions.
- In December 2022, Sonde raised a $19.25 million Series B investment round led by Partners Investment, with participation from NEOM Company, KT Corporation and existing investors, including co-founders PureTech Health and M Ventures.
- In January 2022, Sonde announced the signing of a multi-year strategic partnership with GN Group to research and develop commercial vocal biomarkers for mild cognitive impairment associated with hearing loss.
Expected Milestones
- Sonde expects to continue development of the voice-based artificial intelligence platform to detect changes in health and validate new products in the areas of fatigue and cognitive impairment in 2025.

Note: Sonde has obtained Institutional Review Board (IRB) approval independently or in collaboration with partner institutions that covers all past and ongoing human data collection for research in the U.S. and abroad. We have two board designees on the board of directors of Sonde, but Sonde has its own independent management team. Our role in the development of Sonde’s therapeutic candidates is through our representation on its board of directors and our role as a majority shareholder. Sonde is well-protected with a robust intellectual property portfolio. Sonde was incorporated in February 2015.

Sonde launched Sonde Mental Fitness, a voice-enabled mental health detection and monitoring technology that uses a brief voice sample to evaluate mental well-being, and has initiated research and development to expand its proprietary technology into mental fitness, respiratory disease, and other health, wellness and safety use cases. Additionally, the company’s Vocal Biomarker program has demonstrated the potential to screen and monitor for disease using information obtained from an individual’s voice on commonly owned devices, such as smartphones and smart speakers, and it has the potential to fundamentally change the way mental and physical health is screened and monitored.