Experts Diverge on the Necessity of Informing Pregnant Women About Similar Vaccine's Risks in Pfizer's RSV Trial. A contentious discussion has emerged regarding Pfizer's responsibility to inform pregnant participants in its respiratory syncytial virus (RSV) vaccine trial about the halted trial of a similar vaccine due to … [Read more...] about Ethical Debate Surrounds Pfizer’s Disclosure in RSV Vaccine Trial for Pregnant Women