Abatacept May Increase Femoral Neck Bone Mineral Density in Rheumatoid Arthritis

Abatacept was superior at increasing bone mineral density (BMD) in the femoral neck compared with other biologic disease-modifying antirheumatic drugs (bDMARDs), and may offer good efficacy for improving BMD in rheumatoid arthritis (RA), according to findings published in Rheumatology International.

To investigate how abatacept would affect BMD and bone metabolic markers in RA compared with other bDMARDs, researchers conducted a prospective, comparative, nonrandomized study (the AIRTIGHT study; UMIN000005570).

Researchers divided 165 patients with RA into abatacept (n=50) and nonabatacept groups (n=115). Dual-energy X-ray absorptiometry was used to evaluate percentage change in BMD at the lumbar spine and femoral neck. 

Urinary levels of cross-linked N-telopeptide of type I collagen were used as a marker of bone resorption, and bone-specific alkaline phosphatase was used as a marker of bone formation. There were no significant differences in 1-year completion rates between the abatacept (64%) and nonabatacept (72%; P =.387) groups.

The percentage change in BMD at the femoral neck was significantly higher in the abatacept group (0.97%) than in the nonabatacept group (−2.19%, P =.026). However, no significant difference was seen in the percentage change in BMD at the lumbar spine between the abatacept group (−0.40%) and the nonabatacept group (−1.67%, P =.524). The researchers found no significant differences in changes to urinary levels of cross-linked N-telopeptide of type I collagen or bone-specific alkaline phosphatase.

The researchers concluded that abatacept treatment was significantly associated with increased BMD at the femoral neck (odds ratio [OR], 8.84; 95% CI, 1.08-72.4; P =.04), and baseline lumbar osteoarthritis was significantly associated with BMD at the lumbar spine (OR, 2.97; 95% CI, 1.23-7.13; P =.02). “The efficacy of [abatacept] for increasing BMD at the femoral neck was superior to that of other bDMARDs. [Abatacept] may offer good efficacy for improving BMD at the femoral neck in patients with RA,” the researchers wrote.

Limitations of the study include that patients were not divided randomly into groups, and the data contain some degree of selection bias; the sample size was too small to compare effects of each bDMARD on BMD, and the discontinuation rate was high in both groups because the trial was performed under real clinical conditions.

Disclosures: Prof. Koike has received research fees, consulting fees, or other remuneration from AbbVie, Astellas Pharma Inc., Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, Ono Pharmaceutical, Pfizer, Takeda Pharmaceutical, Teijin Pharma, and UCB. Prof. Inui has received research grants and/or speaking fees from Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Astellas Pharma Inc., AbbVie, Eisai Co., Ltd., MSD K.K., Bristol-Myers K.K., Takeda Pharmaceutical Co., Ltd. and Janssen Pharmaceutical K.K. Dr Okano received speaking fees from AbbVie.

Reference

Tada M, Inui K, Sugioka Y, Mamoto K, Okano T, Koike T. Abatacept might increase bone mineral density at femoral neck for patients with rheumatoid arthritis in clinical practice: AIRTIGHT study [published online January 2, 2018]. Rheumatol Int. doi: 10.1007/s00296-017-3922-z