The primary outcome was a composite of fetal death at or beyond 10 weeks' gestation, pre-eclampsia with severe features, and placental insufficiency requiring delivery before 34 weeks.² Nine of 45 evaluable patients experienced this composite adverse pregnancy outcome, an incidence of 20% (95% CI, 9.6%-34.6%).² The result met the trial's predefined efficacy threshold and was lower than rates reported in historical controls, according to the published results.²
Certolizumab pegol secondary outcomes and safety in APS pregnancy
Among evaluable patients, median gestational age at delivery was 36.5 weeks.² Neonatal survival to hospital discharge was 93%, and deliveries among patients who met the composite adverse outcome criteria, primarily pre-eclampsia, occurred after 30 weeks' gestation.² These secondary findings were reported alongside the primary result in the published IMPACT analysis.²
Key Facts
What is certolizumab pegol's breakthrough therapy designation for?
The FDA granted Breakthrough Therapy designation to certolizumab pegol (Cimzia) for preventing placenta-mediated adverse pregnancy outcomes in pregnant women with antiphospholipid syndrome who are lupus anticoagulant positive and have prior obstetric or thrombotic events.¹
What did the IMPACT trial show?
In the phase 2 IMPACT trial, nine of 45 evaluable patients experienced the composite primary adverse pregnancy outcome, an incidence of 20% (95% CI, 9.6%-34.6%), with no serious infections, new lupus cases, or severe flares reported.²
How does certolizumab pegol work in APS pregnancy?
Certolizumab pegol is a TNF inhibitor; UCB cites evidence implicating TNF-mediated inflammation in APS-related pregnancy complications as the rationale for its use in this population.¹
No serious infections, new cases of lupus, or severe disease flares were reported during the treatment period, according to the published trial results.²
Jane E. Salmon, MD, Collette Kean Research Chair at the Hospital for Special Surgery and co-lead investigator of the IMPACT trial, said, “For women living with APS, pregnancy can be an especially challenging and uncertain experience. Today's designation represents an encouraging step forward in efforts to improve outcomes for women of childbearing age and their families.”¹
Donatello Crocetta, Chief Medical Officer and Global Head of Medical Affairs at UCB, added, “This designation is a testament to UCB's commitment to advancing innovation in areas of significant unmet need, including our long-standing focus on supporting women of childbearing age.”¹
UCB said the designation builds on the company's broader focus on medicines for women of childbearing age, and the company plans continued engagement with the FDA as development in this indication proceeds.¹
References
Branch DW, et al. Certolizumab pegol to prevent adverse pregnancy outcomes in patients with antiphospholipid syndrome and lupus anticoagulant (IMPACT): results of a prospective, single-arm, open-label, phase 2 trial. Ann Rheum Dis. 2025;84(7):1011-1022.