South Korea’s Celltrion said Thursday it has selected Japanese drugmaker Nippon Kayaku to handle the sales of its Truxima, a biosimilar copy of Roche’s lymphatic cancer drug Rituxan, on the Japanese market.

Celltrion Healthcare, the marketing and sales subsidiary of Celltrion, and Nippon Kayaku have signed a partnership under which the Japanese drugmaker will sell Truxima in Japan.

Rituxan, also known as Mabthera, achieves sales of around 400 billion won ($354 million) in Japan annually. Celltrion and Nippon Kayaku plan to work on securing sufficient clinical trial records in Japan proving the safety and efficacy of Truxima, with aims to seek approval by local regulators. Celltrion has yet to announce an estimated filing timeline.

Nippon Kayaku is also Celltrion’s sales partner in the Japan market for two other biosimilars it has developed -- Remsima referencing Remicade and Herzuma referencing Herceptin.

Meanwhile, Celltrion filed Herzuma for approval by Japan’s Ministry of Health, Labour and Welfare earlier this month. It expects to launch its Herceptin biosimilar in Japan next year.

By Sohn Ji-young (jys@heraldcorp.com)