SK Bioscience Wins Key Patent Battle Over Pfizer in Korea

Supreme Court Ruling Opens International Doors

In a significant legal development, SK Bioscience has secured a victory in a prolonged patent dispute with Pfizer concerning pneumococcal vaccine technology in South Korea. The decision, made by the Supreme Court of Korea, affirms that SK did not infringe upon Pfizer’s composition patent related to Prevnar 13 when it exported components and finished research doses of its own vaccine, PCV13, to Russia.

According to SK's official press release, "Korean regulators approved SK’s 13-valent pneumococcal conjugate vaccine under the name SKYPneumo back in 2016." However, due to a prior settlement involving Pfizer, SK has been barred from producing and distributing the vaccine domestically until 2027, when the contested patents are scheduled to expire.

Legal Dispute Dates Back to 2020

Pfizer initiated the most recent lawsuit in 2020 after SK's 2018 and 2019 exports of PCV13 components and doses to a Russian pharmaceutical partner. Pfizer argued that these actions constituted a violation of an earlier settlement agreement. Nonetheless, the Korean Supreme Court has sided with SK, clearing the way for broader international vaccine exports.

In response to the decision, SK CEO Jaeyong Ahn remarked, "This latest court decision is meaningful in that it ensures a competitively developed vaccine in Korea does not go to waste but instead finds new opportunity. We will leverage this momentum to improve access to premium vaccines, contribute to a stable global vaccine supply, and achieve sustainable growth."

Expanding Global Vaccine Access

While SK must still wait until 2027 to commercialize SKYPneumo domestically, the company intends to pursue new international business ventures. These plans include exporting vaccine components to markets with high demand, particularly in Southeast Asia and Latin America. Additionally, SK is actively exploring technology transfer arrangements through partnerships in these regions.

Next-Generation Vaccine Development

In parallel with its legal efforts, SK is advancing its research and development capabilities. The company is collaborating with Sanofi on a 21-valent pneumococcal conjugate vaccine, which entered Phase 3 clinical trials in late 2024. SK and Sanofi are also working on a next-generation pneumococcal vaccine aimed at offering broader protection than existing options.

Broader Legal Momentum for SK

SK’s legal successes extend beyond Pfizer. In April 2025, the company also achieved a favorable ruling in a patent invalidation suit against Moderna, successfully challenging a Korean patent related to mRNA vaccine technology. This marks another strategic win for the company as it continues to build its portfolio and expand its influence in the global vaccine industry.

Highlights

• SK Bioscience won a patent lawsuit against Pfizer in South Korea over its 13-valent pneumococcal vaccine, SKYPneumo.
• The Korean Supreme Court ruled that SK did not infringe Pfizer’s patent by exporting vaccine components to Russia.
• Although domestic sales are barred until 2027, SK can now export to global markets, including Southeast Asia and Latin America.
• SK is developing a 21-valent pneumococcal vaccine with Sanofi and pursuing next-generation immunizations.
• SK also recently invalidated Moderna's Korean mRNA vaccine patent, marking a broader legal and strategic success.