CEO Vivek Ramaswamy told BioWorld Today that the special protocol assessment (SPA) from the FDA for Axovant Sciences Ltd.'s new phase III trial with RVT-101, a 5-hydroxytryptamine6 (5-HT6) serotonin receptor antagonist to treat Alzheimer's disease (AD), should bolster confidence that his firm is pursuing "the best-validated target" for the stubborn indication.