Background Abatacept (ABT), a selective co-stimulation modulator, is the first in a new class of biologic agents for the treatment of rheumatoid arthritis (RA). Since ABT is often used as second line biologic, it would be important to clarify the impact of the type of previous biologics on ABT efficacy. Additionally, since ABT has also been used as first line biologic in Japan, it is also important to demonstrate the clinical data in biologic naïve patients compared to the patients with previous biologic treatment.
Objectives We studied whether the history of and the type of previous biologic treatment had any impact on the ABT clinical efficacy in RA patients.
Methods All RA patients who underwent ABT treatment for at least 24 weeks (n=111) at Nagoya University Hospital and 12 other institutes (Tsurumai Biologics Communication Study Group ) were enrolled in this study. Demographic data at baseline and the following parameters of disease activity (tender joint count (TJC) and swollen joint count (SJC) on 28 joints, patient global assessment (VAS), ESR, and serum CRP and MMP-3 levels during 24 weeks. We compared these clinical data between the patients without previous biologic history (Naïve, n=49) and those with previous biologic treatment (Switch All, n=62). The patients with one previous biologic (Switch 2nd, n=33), those with more than two previous biologics (Switch 3rd-, n=29), and Naïve group were compared each other. We also compared clinical data between the patients with previous or past tocilizumab treatment (Switch TCZ, n=16), those without TCZ treatment (Switch TNF, n=46), and Naïve group. The last observation carried forward (LOCF) method was used in each analysis.
Results In the baseline characteristics data, there was no significant difference between Naïve and Switch All group, such as mean age (64.8 and 61.9), disease duration (8.7 and 11.9 years), DAS28 (4.4 and 4.6), and CRP (2.0 and 2.5 mg/dL). Although Switch All group showed significant DAS28 decreasing at week 24 compared to week 0, it was significantly higher than that in Naïve group (Fig. A-1). As shown in Fig. A-2, DAS28 at week 24 was significantly decreased in both Switch 2nd and Switch 3rd- group compared to week 0, and no significant difference was seen between these two groups. As shown in Fig. A-3, Switch TCZ group did not show statistically significant DAS28 decreasing at week 24 compared to week 0, and it was significantly higher than that in Switch TNF and Naïve group. Additionally, the percentage of the patients who achieved low disease activity (DAS28<3.2) in Switch TCZ group (12.5%) was apparently lower than that in Naïve (63.3%) or Switch TNF group (45.7%) (Fig. B).
Conclusions The patients with the history of biologics treatment demonstrated significant improvement in RA disease activity, although the responsiveness to abatacept seemed to be better in the biologic naïve patients. However, abatacept demonstrated only inadequate efficacy in the patients with tocilizumab treatment history.
Disclosure of Interest N. Takahashi: None Declared, T. Kojima Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda Pharmaceutical, Bristol-Myers Squibb, K. Funahashi: None Declared, D. Kato: None Declared, H. Matsubara: None Declared, Y. Hattori: None Declared, N. Ishiguro Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda Pharmaceutical, Bristol-Myers Squibb