The Rise of South Korea’s Weight-Loss Pill Pioneer: Sam Chun Dang’s Journey to Billion-Dollar Success
South Korea’s pharmaceutical landscape is witnessing an extraordinary success story with Sam Chun Dang Pharm (SCD), whose shares have skyrocketed by more than 75% this month alone. This remarkable surge comes amid growing investor excitement about the company’s development of oral versions of popular weight-loss medications that currently exist only as injections. The market enthusiasm has catapulted the company’s 75-year-old chairman, Yoon Dae-in, into the billionaire club, with Forbes estimating his net worth at $2.1 billion. Yoon, who will turn 76 in March, holds a substantial 34% ownership stake in the company, along with a modest interest in OPTUS Pharmaceutical, SCD’s specialized eye-drop manufacturing division. This financial milestone represents not just personal success but reflects the growing global interest in innovative weight management solutions.
At the heart of SCD’s breakthrough is its proprietary S-Pass technology, an innovative drug delivery system that transforms injectable medicines into convenient oral pills. This advancement addresses a critical gap in the current weight-loss medication market, where effective treatments like semaglutide (Ozempic/Wegovy) and tirzepatide (Mounjaro/Zepbound) are available only as injections, creating barriers to widespread adoption. The company’s technological innovation has attracted major international attention, most recently culminating in a partnership with Japanese pharmaceutical giant Daiichi Sankyo. Announced just last Thursday, this collaboration aims to jointly develop and commercialize SCD’s weight-loss pill specifically for the Japanese market. While the financial specifics remain under wraps, the market has responded enthusiastically, driving SCD shares up by nearly 40% since the announcement. Korea Investment & Securities has further validated the company’s approach by naming SCD its “recommended stock of the week,” specifically citing the S-Pass technology’s “potential for clinical success as a formulation technology for oral obesity and diabetes treatments.”
Beyond its groundbreaking work in oral medication delivery, SCD has developed another innovative drug delivery system: microsphere-based long-acting injectables. This technology creates timed-release micro-pellets that slowly discharge medication over several months, dramatically reducing the frequency of required injections. The value of this innovation was recently recognized in a landmark deal with Japan’s Takeda Pharmaceutical. On January 7, SCD announced an agreement potentially worth up to $2 billion for the exclusive rights to sell a long-acting injectable version of leuprorelin—a hormone medication used to treat prostate cancer—in the United States. The deal structure includes approximately $100 million in upfront and milestone payments, with the remaining $1.9 billion coming from an equal profit-sharing arrangement. This partnership validates SCD’s technological capabilities and provides significant capital to fuel further research and development initiatives.
The company’s financial performance reflects its technological achievements and market optimism. In the first nine months of 2025, SCD reported revenue of 165.5 billion won (approximately $113 million), representing a 6.3% year-over-year increase. More impressively, net income surged by 76% compared to the same period in the previous year, reaching 70 billion won. This robust financial growth underscores the company’s successful transition from a traditional pharmaceutical manufacturer to an innovation-driven enterprise at the cutting edge of drug delivery technologies. Beyond its headline-grabbing weight loss and long-acting injectable technologies, SCD maintains a diverse portfolio that includes active pharmaceutical ingredients for treatments addressing dry-eye disease and high blood pressure, creating multiple revenue streams and mitigating investment risk.
The history of SCD traces back to 1943 during the Japanese occupation of Korea (1910-1945), when it was established as Chosun Sam Chun Dang. While information about its original founder remains scarce, the company’s modern trajectory began in 1986 when Yoon Dae-in acquired it using family funds following the completion of his MBA studies at Long Island University in New York. Yoon, whose father had built a small empire of medical centers and educational institutions, recognized the potential of the pharmaceutical sector and transformed the traditional company into an innovation-focused enterprise. This vision culminated in SCD’s listing on Korea’s technology-focused Kosdaq stock exchange in 2000, where it raised 9.1 billion won in its initial public offering. Until 2022, Yoon shared CEO responsibilities with his son-in-law Chun In-seok, who joined the company in 2014 and continues as CEO today. The transition represents a carefully orchestrated succession plan while maintaining the founding family’s influence over the company’s strategic direction.
Yoon’s ascension to billionaire status places him among an impressive constellation of South Korean biotech and pharmaceutical leaders who have built enormous wealth through healthcare innovation. This elite group includes Celltrion’s Seo Jung-jin with an estimated $8.5 billion net worth, Alteogen’s Park Soon-jae at $2.7 billion, Caregen’s Chung Yong-ji with $2.1 billion, ABL Bio’s Lee Sang-hoon at $1.6 billion, PharmaResearch’s Jung Sang-soo with $1.2 billion, and Voronoi’s Hyuntae Kim at $1 billion. South Korea’s emergence as a powerhouse in pharmaceutical innovation reflects the nation’s broader economic transformation from manufacturing to knowledge-based industries. SCD’s success story—particularly its breakthrough in oral formulations of weight-loss medications—highlights how technological innovation in healthcare can create enormous value by addressing unmet patient needs. As global obesity rates continue to rise and demand for effective treatment options grows, SCD’s pioneering work positions the company at the intersection of one of healthcare’s most promising and potentially lucrative frontiers.
