UCB will present results from three studies for CIMZIA® (certolizumab pegol), a PEGylated fragment crystalized (Fc)-free tumor necrosis factor inhibitor (TNFi), for women of childbearing age living with chronic immune-mediated diseases and people with rheumatoid arthritis (RA) and high rheumatoid factor (RF) levels. These data will be presented at the European Congress of Rheumatology, EULAR 2024, and provide evidence to inform personalized treatment decisions for patient populations with high unmet need. CHERISH study results (abstract POS0888): Results from the open-label, phase 1b CHERISH study in women with immune-mediated diseases, including psoriatic arthritis (PsA), axial spondyloarthritis (axSpA), and RA, found that the range of blood plasma concentrations of certolizumab pegol throughout and after pregnancy were similar to those observed in studies of non-pregnant women with PsA, axSpA, and RA, suggesting that women may maintain stable therapeutic levels of certolizumab pegol throughout pregnancy.

These data build on previous pharmacokinetic studies ? CRIB and CRADLE ? that showed minimal-to-no transfer from mother to baby through the placenta or breast milk.

The latest study, CHERISH, expands on the data available by focusing on certolizumab pegol and stability of exposure for the mother. The safety profile observed in the CHERISH study was consistent with the known safety profile of certolizumab pegol, which includes extensive pharmacovigilance data. The CHERISH, CRIB, and CRADLE studies are pharmacokinetic studies.

There are no adequate and well-controlled studies of CIMZIA in pregnant women or lactation to demonstrate efficacy or establish safety. RF-drug interaction research (abstract POS0722): A further study presented at EULAR provided molecular insights into why individuals living with RA and high RF levels generally maintain consistent drug concentrations and may experience consistent clinical outcomes when treated with certolizumab pegol. An in vitro study found that three different RF antibodies all bound to Fc-containing TNFi adalimumab and enabled the formation of large immune complexes.

Conversely, the RFs were unable to interact with certolizumab pegol, due to its lack of Fc domain, and no complexes with RF were formed. REALISTIC trial results (abstract AB0638): Insights into the effects of certolizumab pegol in people living with RA and high RF levels were investigated in a post-hoc analysis of the double-blind, placebo controlled, phase 3b REALISTIC trial ? also accepted as an abstract at EULAR.

Clinical response to certolizumab pegol was analyzed according to the highest quartile RF level compared with the lowest and in people with a previous inadequate response to TNFi versus those with no prior TNFi exposure. Responses were greater with certolizumab pegol versus placebo in all groups. In patients who previously had an inadequate response to TNFis, responses among those who were randomized to placebo were lower in the high RF group compared with the low RF group at week 12.

By contrast, clinical responses to certolizumab pegol treatment were similar between those with high and with low RF levels, indicating that RF level does not influence a patient's response to certolizumab pegol. These certolizumab pegol data together demonstrate how tailored treatment approaches can support specific groups of patients.