As technology evolves and medical needs diversify, the pharmaceutical industry must accelerate its openness. This study analysed inter-organizational alliances in R&D for the new modality of oligonucleotide therapeutics to explore the requirements for establishing new markets. The results confirmed that the market has developed in stages, employing open innovation for different purposes according to technological progress. At each stage, it was crucial to form platforms among biotech companies on the drug discovery side, among pharmaceutical companies on the regulatory side and contract development manufacturing organizations (CDMOs) on the manufacturing side. These findings clarify the dynamics of open innovation in the biopharmaceutical industry and provide strategic implications for sustainable value creation in drug R&D.