Celltrion Begins Recruiting US Patients for Phase 3 Study of Subcutaneous CT-P13

Celltrion has announced that it has begun recruiting patients with inflammatory bowel disease in Ohio for a phase 3 clinical trial of its subcutaneous formulation of biosimilar infliximab, CT-P13 (Inflectra, Remsima). The study is intended to support an application for the formulation to the FDA.

The Republic of Korea—based drug maker indicated that the FDA has exempted the company from having to conduct phase 1 or phase 2 clinical studies, given the amount of clinical data that the company has already generated in support of its submission of the product to the European Medicines Agency (EMA).

The subcutaneous formulation of the biosimilar infliximab has already been submitted for approval in Europe, and the data package supporting its application included data from a study in patients with rheumatoid arthritis (RA).¹

The trial investigated the pharmacokinetics, efficacy, and overall safety of the subcutaneous biosimilar versus the already-approved intravenous (IV) version over 1 year. A total of 48 patients were randomly assigned to 4 cohorts: The IV cohort received the IV drug every 8 weeks and the SC cohorts received 90 mg, 120 mg, or 180 mg, respectively, every 2 weeks up to week 54.

Overall, the efficacy and safety results of subcutaneous CT-P13 up to week 54 were comparable with those of the IV formulation, and the safety profiles of the 2 formulations of the drug at week 6 were comparable and consistent with the known profile of infliximab.

The subcutaneous biosimilar was also studied in a phase 1 trial in patients with Crohn disease.² Forty-four patients were given the IV formulation of CT-P13 at weeks 0 and 2, then randomized to 4 cohorts. One continued to receive the IV biosimilar every 8 weeks, while the second, third, and fourth cohorts each received the subcutaneous biosimilar at doses of 120 mg, 180 mg, and 240 mg, respectively, every 2 weeks up to week 54.

At week 30, overall clinical response rates among cohorts were similar. Clinical remission was numerically higher in the subcutaneous therapy cohorts at week 54. The safety profiles of the IV and subcutaneous formulations were similar.

If the subcutaneous version of the biosimilar is eventually approved, Celltrion has indicated that, in addition to making an appealing choice for patients who are satisfied with treatment with IV infliximab but who prefer or need a subcutaneous route of administration, the new formulation of CT-P13 could compete with brand-name adalimumab (Humira), another subcutaneously administered anti—tumor necrosis factor therapy.

References

1. Yoo DH, Jaworski J, Matyska-Piekarska E, et al. A novel formulation of CT-P13 (infliximab biosimilar) for subcutaneous administration: 1-year results from a part 1 of phase 1/3 randomized controlled trial in patients with active rheumatoid arthritis. Presented at: The European League Against Rheumatism European Congress of Rheumatology 2019; June 12-15, 2019; Madrid, Spain. Abstract FRI0128.

2. Byong DY, Byung IJ, Borzan V, et al. A novel formulation of CT-P13 (infliximab biosimilar) for subcutaneous administration: 1-year result from a phase 1 open-label randomized controlled trial in patients with active Crohn’s disease. Presented at: Digestive Disease Week 2019; May 18-21, 2019; San Diego, CA. Abstract Tu1715.