Proactive TDM Superior to Standard Therapy Among Patients IMIDs

In a recent clinical trial, researchers found that proactive therapeutic drug monitoring (TDM) during maintenance infliximab therapy was more likely to lead to sustained disease control for patients with immune-mediated inflammatory diseases than treatment without TDM.

Proactive TDM is the practice of individualizing treatment based on scheduled assessments of serum drug levels. This alternative to standardized therapy may optimize efficacy and safety of infliximab and other biologic drugs, but it isn’t clear whether proactive TDM improves clinical outcomes during maintenance therapy.

This randomized, parallel-group, open-label clinical trial was conducted to assess whether proactive TDM during maintenance therapy with infliximab improves treatment efficacy as compared with standard infliximab therapy without TDM. Outcomes were sustained disease control without disease worsening, as determined by disease-specific composite scores, or consensus about disease worsening between patient and physician, leading to a major change in treatment.

There were 458 patients total with rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, ulcerative colitis, Crohn disease, or psoriasis undergoing maintenance therapy with infliximab. Of those patients, 454 (mean age, 44.8 [SD, 14.3] years; 216 women [49.8%]) were included in the full analysis set. Patients were randomized to either the proactive TDM group (n = 228), with dose and interval adjustments based on scheduled monitoring of serum drug levels and antidrug level monitoring, or the standard therapy group (n = 230) without drug and antibody level monitoring. The trial took place over a 52-week study period, with the final follow-up on December 14, 2020.

Sustained disease control without disease worsening was seen in 167 patients (73.6%) of the TDM group and 127 patients (55.9%) of the standard therapy group. The researchers wrote, “the estimated adjusted difference was 17.6% (95% CI, 9.0%-26.2%; P < .001) favoring TDM.”

Adverse events were reported in 137 patients (60%) in the TDM group, and 142 patients (63%) in the standard therapy group.

Further areas of research include comparing proactive TDM with reactive TDM, determining the effects of long-term disease complications, and evaluating the cost-effectiveness of this approach.

—Allison Casey

Reference:
Syversen SW, Jørgensen KK, Goll GL, et al. Effects of therapeutic drug monitoring vs standard therapy during maintenance infliximab therapy on disease control in patients with immune-mediated inflammatory diseases: A randomized clinical trial. JAMA. 2021;326(23):2375-2384. doi:10.1001/jama.2021.21316