SK Biopharma, 1STBIO Sign Parkinson’s Drug Deal

1ST Biotherapeutics Inc. (1STBIO) and SK Biopharmaceuticals Co. Ltd. have entered into an exclusive global licensing and strategic equity investment partnership to advance 1ST-104, 1STBIO’s oral small-molecule candidate for Parkinson’s disease.

Under the agreement, 1STBIO will receive a $1.8 million upfront payment. The licensing deal is worth up to $314.8 million, including a $1.8 million short-term milestone upon candidate selection and additional development and commercial milestones. 1STBIO is also eligible for tiered royalties on global net sales. Separately, SK Biopharmaceuticals made a $2.2 million strategic equity investment in 1STBIO to support a long-term partnership.

Advancing 1ST-104

1ST-104 is designed to treat Parkinson’s disease through dual inhibition of LRRK2 and c-Abl. LRRK2 is considered directly linked to Parkinson’s disease pathogenesis, but some Type 1 LRRK2 inhibitors have faced development challenges after pulmonary findings in preclinical studies.

To address those limitations, 1STBIO developed 1ST-104 as a next-generation Type 2 LRRK2 inhibitor. Its Type 2 binding mode is intended to differentiate it from conventional Type 1 inhibitors, and preclinical studies have shown target selectivity and blood-brain barrier permeability. Since 2024, 1STBIO has also participated in LITE, the LRRK2 Investigative Therapeutics Exchange supported by The Michael J. Fox Foundation for Parkinson’s Research, to support global scientific and technical collaboration.

“This agreement serves as a strong validation of 1ST Biotherapeutics’ proprietary discovery capabilities in next-generation target identification and lead optimization,” said Jamie Jae Eun Kim, CEO of 1ST Biotherapeutics. “It marks a major milestone by uniting our early-stage R&D strength with SK Biopharmaceuticals’ proven global development and commercial expertise. Through close collaboration with SK Biopharmaceuticals, we will leverage the strengths of both companies to advance the subsequent development of 1ST-104.”

Donghoon Lee, CEO of SK Biopharmaceuticals, added, “We will work to translate this candidate into successful clinical development, opening up new possibilities for the treatment of Parkinson’s disease.”