Reston,
VA (February 27, 2026)--A new targeted PET/CT tracer can detect treatment
response in rheumatoid arthritis patients in as little as four weeks, and
potentially even at the start of treatment, according to new research published
in The Journal of Nuclear Medicine. Compared to the three to six months currently
required to establish treatment efficacy, this new imaging technique could help
determine the patients who are most likely to respond sooner, allowing non-responders
to pursue more effective therapies.
Rheumatoid arthritis is a disease
characterized by chronic inflammation of synovial tissue in joints, potentially
leading to permanent damage to cartilage and bone, which can affect physical
function and quality of life. Effective treatment is required to prevent or
reduce the risk of permanent damage in accordance with standards of care.
Anti tumor necrosis factor (aTNF) is a successful treatment for many patients with rheumatoid
arthritis; however, it is only effective in 50 to 70 percent. As it can take
three to six months before clinical response can be determined, objective and
accurate tools are needed for early assessment of treatment response and
patient stratification.
"Macrophages (a type of white blood cell), play
a crucial role in the development and continuation of rheumatoid arthritis, and
are a promising biomarker for assessment and monitoring of disease activity," said Wouter van Binsbergen, MSc, MD, PhD, a student at the Amsterdam University
Medical Center in Amsterdam, The Netherlands. "In our study, we utilized a new
PET/CT imaging technique to quantify macrophages and determine their
association with clinical disease activity."
In the study, researchers conducted whole-body
11C-DPA-713 PET/CT scans on 20 rheumatoid arthritis patients
undergoing aTNF treatment. Uptake of the 11C-DPA-713
tracer was quantified by determining the standardized uptake value in 44 joints
at baseline and at four weeks. Mean SUVs of all joints and specific joint
clusters were related to clinical evaluation after 26 weeks using linear
regression analyses. Multivariable analyses, including both PET/CT and clinical
evaluation, were also conducted.
Quantitative 11C-DPA-713 PET/CT
measurements at baseline and four weeks after aTNF
treatment showed significant association with clinical disease activity at 26 weeks. Furthermore,
the addition of specific clinical data to SUV data of certain joints improved
the potential predictive value in multivariable regression analyses at baseline
and 4 weeks in specific instances.
"These findings show that non-invasive
assessment and monitoring of macrophages using PET/CT has value to predict very
early potentially already at baseline the outcome of anti-TNF treatment in
rheumatoid arthritis patients, said van Binsbergen. On a larger scale, this
work supports the clinical application of molecular imaging and use of novel
immune cell targeting tracers for development of personalized treatment and
stratification strategies in rheumatoid arthritis and beyond."