A new pilot trial suggests a targeted apheresis technique may offer a disease-specific treatment for severe preeclampsia, a life-threatening pregnancy complication currently managed only by delivery.
The approach uses an extracorporeal device with high-affinity antibodies to selectively remove soluble Fms-like tyrosine kinase 1 (sFlt-1), a placental protein central to preeclampsia's pathogenesis. In a two-phase, single-arm open-label study, the intervention was tested in women with very preterm preeclampsia.
Phase A included seven women receiving single ascending doses. Before treatment, mean sFlt-1 levels were 15,120 pg/mL. Maternal and fetal vital signs remained stable.
Phase B evaluated nine women with repeated dosing. Median gestational age was 30.3 weeks. Each apheresis session reduced circulating sFlt-1 by an average of 16.7% and mean arterial pressure by 4.1 mmHg. The study found a strong correlation (R=0.63) between drops in blood pressure and reductions in sFlt-1 levels.
Pregnancy continuation lasted a median of 10 days post-admission. Neonatal birth weights remained stable or improved. Adverse events were limited to mild hypocalcemia, skin hemorrhage at the puncture site, and false labor.
The investigators, led by Dr. Ravi Thadhani, conclude that controlled trials are necessary to confirm safety and efficacy.