Currently, not enough time or funding is invested in the pre-clinical and early phase clinical testing of new therapies to treat pregnancy complications. At present, we often jump from animal models to clinical trials using a single dose of the therapy, and test it in women with a "broad" and/or severe phenotype of disease. We do this without gathering pharmacokinetic/pharmacodynamic/dosing information from these women, and then are surprised when a study shows no effect, and the drug is abandoned.
We (funders, scientists and clinicians) need to be prepared to do the hard work to gather all the required information to understand how and why drugs work in a defined cohort of pregnant women. We need to know we are giving an appropriate dose to achieve the effect we are seeking, and that the therapeutic concentration in the plasma is maintained throughout the trial. We need to know that our cohort exhibits the pathology we are aiming to correct, and that we have effective and accurate measure(s) of that pathology, so we can quantify the patient's response to the therapy. We also need to know that the disease is not so severe that it cannot be rescued by the intervention we are testing. Robustly answering all of these questions will allow us to design more effective clinical trials and not lead to the premature dismissal of potentially effective therapies because of poor planning.