Celltrion (068270.KS) has begun the domestic approval process for the subcutaneous (SC) formulation of its breast cancer treatment Herzuma (CT-P6). The move is interpreted as a strategy to expand its product lineup beyond the existing intravenous formulation and increase market share.
Celltrion announced on Friday that it has filed for product approval of "CT-P6 SC (active ingredient: trastuzumab)" with the Ministry of Food and Drug Safety. CT-P6 SC is the subcutaneous formulation of Herzuma, indicated for early breast cancer and metastatic breast cancer. The company filed for approval covering all indications approved for the original drug.
According to pharmaceutical market research firm IQVIA, the global trastuzumab market reached approximately $3.348 billion (about 5 trillion won) last year. The domestic market, based on distribution value, stands at approximately 79.4 billion won, with the original drug Herceptin leading the market at 46 billion won. The biosimilar market is led by Celltrion's Herzuma and Samsung Bioepis's Samfenet. Against this backdrop, Celltrion's expansion into the Herzuma subcutaneous formulation is seen as a strategy to expand market share by leveraging dosing convenience.
According to Celltrion, this approval filing is based on results from a Phase 1 clinical trial conducted in Korea. The trial enrolled 203 healthy adult men aged 19 to 55. It was a double-blind, randomized, active-controlled study comparing CT-P6 SC and the subcutaneous formulation of Herceptin to evaluate pharmacokinetics, safety, and immunogenicity.
In the trial results, the 90% confidence intervals for the primary endpoints — area under the blood drug concentration-time curve (AUC0-inf) and maximum blood concentration (Cmax) — fell within the predefined equivalence range of 80-125%, demonstrating pharmacokinetic equivalence between CT-P6 SC and the subcutaneous formulation of Herceptin.
No meaningful differences between the two groups were observed in safety and immunogenicity evaluations either. Adverse reactions following single administration were reported in 89.5% of all subjects, but the rate was similar to that of Herceptin, and most were mild or moderate. No serious adverse reactions occurred. No clinically meaningful safety impact related to immunogenicity was observed.
Celltrion plans to sequentially pursue overseas approval procedures starting with this domestic filing. "We have completed the Korean approval filing based on the secured clinical data," a Celltrion official said. "We plan to file for approval in various countries going forward." The official added, "Since we have completed approval filings for all indications approved for the original product, we expect to be able to provide treatment options to more patients."
However, the approval filing does not guarantee final approval by regulatory authorities, and commercialization plans could change depending on review results.
