Background: Therapeutic equivalence of CT-P17 to reference adalimumab (ref-adalimumab) has been shown in patients with moderate-to-severe active rheumatoid arthritis (RA) through primary 24-week results [1]. Here, efficacy, pharmacokinetics (PK), safety and immunogenicity results up to 52-week, including transition data from ref-adalimumab to CT-P17 are presented.

Objectives: To evaluate efficacy, PK, safety and immunogenicity when switched from ref-adalimumab to CT-P17 compared to maintaining CT-P17 or ref-adalimumab.

Methods: In this study, 648 moderate-to-severe active RA patients despite methotrexate treatment were randomized (1:1) to either CT-P17 or ref-adalimumab and treated with doses of 40 mg every 2 weeks up to Week 24. Prior to dosing at Week 26, 608 patients were randomized again to either maintaining their treatments or being switched from ref-adalimumab to CT-P17. Efficacy, PK, safety, and immunogenicity were assessed up to Week 52.

Results: After the second randomization, 303 patients continued with CT-P17, 153 patients continued with ref-adalimumab and 151 patients switched from ref-adalimumab to CT-P17 treatments, up to Week 48. Demographics and baseline characteristics were similar among the 3 groups. Sustained and comparable efficacy in terms of ACR20/50/70 response rates was achieved not only in the maintenance groups (CT-P17 or ref-adalimumab) but also in the switched from ref-adalimumab to CT-P17 group up to Week 52 ( Figure 1 ).

Figure 1.

ACR 20/50/70 Response Rates up to 1 YearAbbreviation: ref-adalimumab, reference adalimumab.Note. There were patients who could not visit the study site due to COVID-19 pandemic and were counted as nonresponder for ACR response at Week 52.

In terms of PK, mean trough serum concentration (Ctrough) were maintained after Week 24 in all 3 groups. The observed mean Ctrough were within the reported therapeutic ranges of ref-adalimumab trough levels in RA patients (5-8 μg/mL).

The safety profile after transition was comparable among the 3 groups ( Table 1 ). The most common treatment-emergent adverse events (TEAEs) was neutropenia. Similar proportions of patients in all 3 groups experienced at least 1 TEAE: injection site reactions, hypersensitivity/allergic reactions and infections. One malignancy (basal cell carcinoma; unrelated) was reported in the ref-adalimumab maintenance group. Safety data accumulated over 1 year also showed comparable results among the 3 groups. Anti-drug antibody (ADA) and neutralizing antibody (NAb) results were similar among the 3 groups. At Week 52, the proportions of patients who had ADA/NAbs were 28.4%/24.8% patients in CT-P17 maintenance, 27.0%/24.3% patients in ref-adalimumab maintenance and 28.3%/26.3% patients in switched to CT-P17 groups.

Conclusion: Single transition from ref-adalimumab to CT-P17 was efficacious and safe without increase in immunogenicity. Also, efficacy, PK, safety and immunogenicity profiles were comparable between CT-P17 and ref-adalimumab up to Week 52.

REFERENCES:

[1]J Kay et al, 2020. Poster Presented at ACR Convergence 2020.

Disclosure of Interests: Daniel Furst Speakers bureau: CME, Consultant of: Amgen, Corbus, Galapagos, Horizon, Kadmon, Pfizer, Talaris, Grant/research support from: Corbus, CSL Behring, Galapagos, Gilead, GSK, Horizon, Kadmon, Novartis, Pfizer, Roche/Genetech, Talaris, Edward Keystone Speakers bureau: Amgen, AbbVie, F. Hoffmann-La Roche Inc., Janssen Inc., Merck, Novartis, Pfizer Pharmaceuticals, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb Company, Celltrion Inc., Myriad Autoimmune, F. Hoffmann-La Roche Inc, Gilead, Janssen Inc., Lilly Pharmaceuticals, Merck, Pfizer Pharmaceuticals, Sandoz, Sanofi-Genzyme, Samsung Bioepis, Grant/research support from: Amgen, Merck, Pfizer Pharmaceuticals, PuraPharm, Jonathan Kay Consultant of: AbbVie, Inc., Boehringer Ingelheim GmbH, Celltrion Healthcare Co. Ltd., Jubilant Radiopharma, Merck & Co., Inc., Pfizer Inc., Samsung Bioepis, Sandoz Inc., Scipher Medicine, UCB, Inc., Grant/research support from: Paid to the University of Massachusetts Medical School: Gilead Sciences Inc., Novartis Pharmaceuticals Corp., Pfizer Inc., Janusz Jaworski: None declared, Rafal Wojciechowski: None declared, Piotr Wiland Speakers bureau: Eli Lilly, Sanofi Aventis, Novartis, Sandoz, Consultant of: Eli Lilly, Novartis, Sandoz, Anna Dudek: None declared, Marek Krogulec: None declared, Sławomir Jeka Speakers bureau: Novartis, Pfizer, Roche, Lilly, Teva, MSD, Abbvie, Sandoz, Egis, Medac, Consultant of: Novartis, Pfizer, Roche, Lilly, Teva, MSD, Abbvie, Sandoz, Egis, Medac, Agnieszka Zielinska: None declared, Jakub Trefler: None declared, Katarzyna Bartnicka-Masłowska: None declared, Magdalena Krajewska-Wlodarczyk Speakers bureau: Abbvie, Eli Lilly, Novartis, Roche, Piotr Klimiuk: None declared, Sang Joon Lee Employee of: Celltrion, Inc., Sung Hyun Kim Employee of: Celltrion, Inc., YunJu Bae Employee of: Celltrion, Inc., GoEun Yang Employee of: Celltrion, Inc., JaeKyoung Yoo Employee of: Celltrion, Inc., TaeKyung Kim Employee of: Celltrion, Inc.