Celltrion’s infliximab biosimilar Remsima has become the most prescribed infliximab product in Japan, 11 years after entering a market where biosimilars have traditionally faced limited price-driven incentives.
According to Celltrion, Remsima captured a 48% share of Japan’s infliximab market in July, based on data from pharmaceutical market research firm IQVIA and local sources. The milestone marks the first time since its Japanese launch in 2015 that Remsima has taken the top position in the market.
Japan presents a different competitive environment for biosimilars compared with many other markets. Because the difference in out-of-pocket costs between originator biologics and biosimilars can be relatively limited, lower prices alone do not necessarily translate into rapid uptake.
Instead, physicians’ prescribing experience, accumulated clinical and real-world data, product familiarity and pharmaceutical companies’ sales capabilities can play a significant role in determining market share.
Local sales strategy builds prescription base
Celltrion has spent years adapting its commercial strategy to these market characteristics. The company has worked with Japanese pharmaceutical company Nippon Kayaku as a distribution partner while strengthening direct sales through its local subsidiary since late 2017.
The combination of a local partner’s distribution network and Celltrion’s own sales organization has helped broaden contact with medical professionals and build a prescription base. Remsima’s long track record in Japan has also contributed to familiarity with the product among physicians.
Celltrion is now extending that approach beyond a single product. Its autoimmune disease portfolio in Japan includes Remsima, adalimumab biosimilar Yuflyma, tocilizumab biosimilar Avtozma and ustekinumab biosimilar Steqeyma.
The broader portfolio could create commercial synergies because the products are used within overlapping physician and hospital networks, allowing the company to offer multiple treatment options across the autoimmune disease market.
Yuflyma currently holds a 21% share of Japan’s adalimumab biosimilar segment, while Avtozma has secured about 10% of the intravenous tocilizumab segment.
Celltrion has also established a significant presence in Japan’s oncology biosimilar market. Herzuma, its trastuzumab biosimilar for breast and gastric cancers, has reached a 78% market share, while bevacizumab biosimilar Vegzelma has captured 64%.
With Remsima’s latest milestone, three Celltrion products now lead their respective molecule markets in Japan.
Remsima SC could broaden infliximab strategy
The next phase of Celltrion’s infliximab business in Japan is expected to center on Remsima SC, the subcutaneous formulation of infliximab.
Celltrion is preparing to launch Remsima SC in Japan in 2027. Adding a subcutaneous option alongside the existing intravenous formulation would give physicians and patients greater flexibility in how infliximab treatment is administered.
In Europe, Remsima SC has expanded treatment options beyond the traditional IV-centered infliximab market. A similar rollout in Japan could allow Celltrion to build on Remsima’s existing prescription base while addressing demand for more convenient administration.
Competition in Japan’s biosimilar market, however, remains intense. Maintaining Remsima’s position will depend on continued accumulation of prescribing data, physician confidence and a commercial strategy tailored to Japan’s regulatory and reimbursement environment.
The broader significance of Remsima’s rise lies in Celltrion’s transition from competing with individual biosimilars to building a wider product portfolio in Japan. The addition of Remsima SC could further extend that strategy by allowing the company to offer both IV and subcutaneous infliximab options.
“Remsima reaching the No. 1 market share position in Japan 11 years after its launch reflects a tailored sales strategy that takes the local pharmaceutical environment into account, supported by the experience and expertise of our local team,” said Kim Ho-woong, senior vice president and head of Celltrion’s Global Sales Division.
“With the launch of Remsima SC next year, we expect the Remsima franchise to maintain stronger growth momentum,” he added.
