A candidate drug for early-stage Parkinson’s disease has failed to show efficacy at Phase 2a despite having demonstrated promise in earlier studies, the co-developer UCB SA announced on 16 December. The drug, minzasolmin, is a small molecule compound designed to inhibit alpha-synuclein misfolding in the brain. Alpha-synuclein is a normal neuronal protein that regulates synaptic vesicle trafficking. However in Parkinson’s disease it misfolds and aggregates into toxic fibrils.