Celltrion announced Friday that it has launched the intravenous formulation of SteQeyma, its autoimmune disease treatment, in Japan — roughly four months after receiving approval from Japan's Ministry of Health, Labour and Welfare in April.

The launch significantly expands the product's treatment scope: alongside its existing indications for psoriasis and psoriatic arthritis, SteQeyma now also covers Crohn's disease. SteQeyma is a biosimilar of ustekinumab, the active ingredient in Johnson & Johnson's Stelara, which has long ranked among the world's best-selling immunology drugs. The expiration of the reference product's key patents has opened the way for lower-priced biosimilar versions such as SteQeyma, which follows Remsima and Yuflyma as the third product in Celltrion's autoimmune portfolio.

Celltrion's Japanese subsidiary plans to accelerate SteQeyma's market penetration by drawing on the sales expertise it has built through existing autoimmune disease products — Remsima, its infliximab biosimilar referencing Johnson & Johnson's Remicade, and Yuflyma, its adalimumab biosimilar referencing AbbVie's Humira. The subsidiary will also leverage its network among key opinion leaders — including gastroenterologists and pharmacists — to expand prescriptions.

According to IQVIA and market data, Remsima and Yuflyma held 46.9 percent and 19.5 percent of the Japanese market, respectively, as of May, maintaining their leading positions among biosimilars. The company's strong biosimilar foothold reflects Japan's broader policy environment: the government has actively encouraged biosimilar adoption to help contain pharmaceutical spending under the country's universal health insurance system as the population ages. Celltrion expects SteQeyma to gain prescriptions rapidly by leveraging marketing synergies and its strengthened portfolio in the autoimmune disease segment.

The availability of SteQeyma in both IV and subcutaneous formulations is also expected to support wider adoption. Patients can receive IV treatment during the induction phase and then switch to the SC formulation for maintenance therapy, allowing treatment to be tailored to the disease stage and a patient's condition. SteQeyma is currently the only ustekinumab biosimilar available in Japan with both IV and SC formulations.

To promote the product among healthcare professionals, Celltrion's Japanese subsidiary plans to participate in major medical conferences later this year, including the Japan Digestive Disease Week and the Japanese Society for Inflammatory Bowel Disease. The company will also strengthen its network with doctors and pharmacists ahead of the launch of Remsima SC in Japan next year.

"We expect this to increase the preference among Japanese healthcare professionals and patients," a Celltrion official said. "We will leverage our existing network to accelerate SteQeyma's market penetration and further strengthen Celltrion's presence in Japan's autoimmune disease market."