Bio + Health

Investing in Leona

Julie Yoo, Jay Rughani, and Eva Steinman Posted December 16, 2025

Most of us think of WhatsApp as a simple messaging app, but in many parts of the world, it also functions as the operating layer of daily life. It’s where families communicate, where businesses run, and increasingly, where healthcare is delivered. In key Latin American countries, it’s estimated that more than 85 percent of physicians rely on WhatsApp to schedule appointments, share results, and manage follow-ups.

But WhatsApp wasn’t built for healthcare. Effective clinical communication requires structured workflows, clear accountability, and reliable tracking of patient needs. Instead, physicians are left navigating dozens of disorganized messaging threads with patients and families, with no visibility into urgency, patient status, and relevant clinical history. The result: hours each day consumed by manual sorting time that should go towards patient care, not inbox management.

The system needs a better answer, and Leona is building it. Leona is an AI-native operating system for providers, built directly into the channel physicians already rely on most: WhatsApp. Through direct integration with the messaging app platform, Leona brings clarity and clinical structure to patient communication organizing messages, flagging urgency, and connecting each exchange to a longitudinal patient record. This co-pilot for clinical messaging is part of a comprehensive practice management platform that facilitates scheduling, documentation, and billing.

The physician adoption is striking: since launching its Latin America beta in April, Leona has expanded organically to thousands of physicians, processing millions of patient interactions across more than a dozen countries, and saving providers up to three hours per day.

As care increasingly lives in messages and mobile moments delivered virtually, asynchronously, and beyond the four walls of the clinic the need for infrastructure that can coordinate clinical workflows becomes increasingly urgent. Leona is building that backbone.

Co-founders Caroline Merin, Tom Chokel, and Arela Solis bring deep operational and technical expertise to one of the region’s most urgent infrastructure challenges. We’re proud to partner with Caroline, Tom, and the whole Leona team as they redefine how care is delivered across Latin America and beyond.

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