Celltrion announced Thursday that its breast and gastric cancer treatment Herzuma (trastuzumab biosimilar), achieved a 74 percent market share in Japan, Asia's key pharmaceutical market, as of November.

Since overtaking the original product in market share during the second quarter of 2021, Herzuma has held the top position for three consecutive years, and is now further distancing itself from competitors.

Herzuma’s success stems from its strong product competitiveness, highlighted by its 2019 approval for a three-week regimen, which was widely adopted in over 90 percent of the Japanese breast cancer market. The achievement is further supported by Japan’s biosimilar-friendly regulatory environment and meticulous analysis of the local pharmaceutical landscape, both of which have combined to drive growth.

In Japan, cancer is one of the main disease categories covered by the Diagnosis Procedure Combination system, a cost-containment policy that encourages the use of biosimilars. Under the DPC system, the Japanese government regulates medical expenses, incentivizing hospitals to prescribe lower-cost medications to retain the savings as profit. Such policy benefits hospitals, governments and patients alike by reducing reimbursement and out-of-pocket costs.

Celltrion’s Japanese subsidiary has leveraged this policy framework by strengthening prescription preference and building networks with key opinion leaders who influence medication choices. Additionally, its dual sales strategy, where both the subsidiary and distribution partners manage product sales, has proven effective.

The strategy has also bolstered the performance of Vegzelma (bevacizumab biosimilar), an oncology product for metastatic colorectal and breast cancers. As of November, Vegzelma captured a 23 percent market share, a threefold increase compared to the same period last year.

“Our exceptional product competitiveness, differentiated sales strategies and a favorable regulatory environment have driven remarkable results for Herzuma and other launched products in Japan,” a Celltrion official said. “We will continue enhancing our sales capabilities for upcoming products in the Japanese market.”

By Kim Hae-yeon (hykim@heraldcorp.com)