Rallybio Corporation published a manuscript detailing a novel model for determining drug dosage in pregnant women, specifically for their drug RLYB212, a monoclonal antibody designed to prevent Fetal and Neonatal Alloimmune Thrombocytopenia (FNAIT). This model incorporates the physiological changes during pregnancy to ensure the safety of both mother and child, a critical aspect often overlooked in traditional pharmacological research. The model-derived dosage will be evaluated in a recently initiated Phase 2 clinical trial for RLYB212.
First, it addresses a critical unmet need in maternal-fetal health. FNAIT, a potentially life-threatening condition, currently has no approved preventative treatments. A successful therapy would represent a significant advancement in the field and positively impact the lives of countless families. Second, this research establishes a precedent for model-informed drug development for pregnant women. This could revolutionize how pharmaceuticals are developed and tested for this vulnerable population, leading to safer and more effective treatments.
The target-mediated drug disposition (TMDD) model described in the manuscript considers the pharmacokinetics of RLYB212 and introduces a new parameter to describe the drug’s effect on eliminating HPA-1a-positive platelets, the root cause of FNAIT. Crucially, the model incorporates physiological changes related to clearance, volume, and intercompartmental transfer rates that occur during pregnancy. This allows for more accurate dosage simulations to ensure both efficacy and safety. The Phase 2 trial will now test the dosage regimen determined by this model. Parallel to this, Rallybio continues a non-interventional FNAIT natural history study, enrolling over 13,000 pregnant women as of November 1, 2024, to further refine their understanding of HPA-1a alloimmunization.
This research holds great promise for the future of FNAIT prevention. Positive results from the Phase 2 trial would validate the TMDD model, paving the way for larger-scale clinical studies and potential regulatory approval of RLYB212. Furthermore, the successful application of this model could encourage broader adoption of model-informed drug development in pregnancy, leading to a new era of safer and more effective therapies for pregnant women and their unborn children. This represents a significant step towards addressing the unique challenges of drug development in this population and improving maternal-fetal health outcomes.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Ferry, a computer data scientist, focuses on the latest clinical trial industry news and trends.
