MAY 25, 2023
There are limited published data on the prevalence of antibodies against the tumor necrosis factor-alpha (TNFα) inhibitors adalimumab and infliximab, which are common therapies for noninfectious uveitis (NIU). The presence of these antidrug antibodies (ADAs) could result in lower circulating drug levels and thus potentially impact treatment.
This was a retrospective, cross-sectional study of 54 patients with NIU treated with TNFα inhibitors who underwent therapeutic drug monitoring with testing for antibodies to adalimumab and infliximab.
None of the 12 patients in the infliximab group developed antibodies to the medication. In the adalimumab group, ADAs were detected in 15 of 42 patients (36%). Patients with ADAs had a lower mean drug level than patients without ADAs (mean 2.8 μg/mL vs 13.6 μg/mL, respectively). A higher mean drug level was seen with the combination of adalimumab and an antimetabolite (methotrexate or mycophenolate mofetil) compared with adalimumab monotherapy (mean 11.0 μg/mL vs 6.8 μg/mL, respectively).
Study limitations include the retrospective design, small sample size, and varying dose regimens of immunomodulatory therapy. The cross-sectional design further limits a definitive conclusion as to whether the ADAs were transient or permanent.
Therapeutic drug monitoring may be able to provide additional information concerning treatment response in NIU. Larger studies will be needed to elucidate these relationships.
Financial Disclosures: Dr. Jessica Shantha discloses no financial relationships.