KT's digital and bio health business chief Im Seung-hyuk (right) and Sonde Health's Chief Executive Officer David Liu (center) and Chief Operating Officer Jim Harper pose for a photo after signing a strategic partnership on Thursday. (KT Corp.)

KT Corp. said Thursday it is making a strategic investment worth $2 million in Sonde Health, a US voice biomarker tech startup that analyzes people’s voice to recognize depression, anxiety and respiratory problems.

The Boston-based firm, equipped with the world’s largest amount of data on voice health, has already secured partnerships with global tech companies like Qualcomm and GN Group.

Vocal biomarkers are gaining renewed attention recently, with voice-related services from smartphones to artificial intelligence speakers flourishing across industries. Fueling the demand is the COVID-19 pandemic that has accelerated the wider adoption of remote medical treatment.

According to market tracker Coherent Market Insights, the market for voice biomarkers is expected to surge to 6 trillion won (4.38 million) by 2027 with an annual growth rate of 15.5 percent.

Starting with the latest investment, KT said it is extending partnerships with Sonde Health to upgrade its AI-based voice services like call centers and AI speakers. The firm added Sonde Health’s technology would be applied to its planned remote health services in Vietnam.

This is KT’s second investment in an overseas health tech firm following a $5 million investment in US bioelectronics developer NeuroSigma in December 2021.