SK bioscience Licensing Deal Targets Access Gaps in RSV Prevention

Incheon, South Korea-based vaccine company, SK bioscience, announced an in-licensing deal on Feb. 3, 2026 with the Gates Medical Research Institute (Gates MRI) for a clinical-stage monoclonal antibody (mAb) candidate for the prevention of respiratory syncytial virus (RSV). The deal expands SK bioscience’s role in global infectious disease prevention while targeting persistent access gaps in low- and middle-income countries (1).

Gates MRI is a nonprofit medical research organization and an affiliate of the Gates Foundation. Under the agreement, SK bioscience will advance development and commercialization of the RSV preventive mAb, which was engineered by Adimab in collaboration with Gates MRI. The candidate is intended for use in newborns and young infants, recognized as a population that remains at high risk for severe RSV disease despite recent advances in prevention strategies (2).

In addition, SK bioscience has secured exclusive rights to commercialize the mAb in high-income countries, along with non-exclusive supply rights in India and Gavi-supported countries, alongside global access commitments aligned with Gates MRI’s charitable mission.

“This newly in-licensed RSV preventive monoclonal antibody candidate is a strategic program that aligns public-health impact with commercial viability, and it will be a key priority for strengthening our portfolio competitiveness over the mid- to long- term,” said Jaeyong Ahn, CEO of SK bioscience, in a company press release (1). “Going forward, we will continue to enhance our business capabilities and drive sustainable growth through technology-driven investment and expanded global partnerships.”

Why does RSV prevention remain an unmet global health challenge?

RSV remains a leading cause of lower respiratory tract disease in infants and young children worldwide, with an estimated 100,000 deaths annually among infants under six months of age. Approximately 97% of these deaths occur in low- and middle-income countries, underscoring the disproportionate burden of disease in settings with limited access to preventive interventions (2).

The in-licensed mAb candidate, known as RSM01, is designed as a single-dose preventive measure intended to provide rapid and durable protection throughout an RSV season. If proven safe and effective, the approach could support broader supply and expand access to RSV prevention, particularly in settings where existing options remain limited by cost or logistical constraints.

What clinical evidence supports the candidate’s advancement?

SK bioscience reported that, in preclinical studies, RSM01 demonstrated strong inhibition of viral infection and replication in both in-vitro and in-vivo models, including activity against certain RSV strains reported to show reduced susceptibility to currently licensed products. In a Phase Ia first-in-human study conducted in healthy adults in the United States, the candidate was generally safe and well tolerated. The data also suggested the potential for sustained protection across an RSV season following a single administration. Based on these findings, the company plans to initiate a Phase Ib clinical trial in infants to accelerate development (1).

Beyond clinical development, the company plans to advance large-scale manufacturing process development to enable affordable supply, particularly for low-resource settings where RSV-associated infant mortality remains high. This strategy reflects a dual focus on commercial viability in developed markets and expanded access in regions with the greatest unmet need.

Global interest in RSV prevention continues to grow. In a World Health Organization global market study, demand for RSV antibodies could increase sharply depending on affordability and inclusion in national immunization programs. The report identifies the RSV segment as a priority public-health market in the coming years with demand projected to increase sharply depending on affordability and inclusion in national immunization programs (3).

References

1. SK bioscience. SK bioscience In-Licenses RSV Preventive mAb Candidate from Gates Medical Research Institute. Press Release. Feb. 3, 2026
2. Dallagiacoma, G.; Lundholma, C.; Smew, A. I.; et al. Risk Factors for Severe Outcomes of Respiratory Syncytial Virus Infection in Children: A Nationwide Cohort Study in Sweden. The Lancet Regional Health—Europe 2025, 58, 101447. DOI: 10.1016/j.lanepe.2025.101447
3. WHO. WHO Global Market Study on Respiratory Syncytial Virus Immunization Products. WHO.int. November 2024.