In April 2012 phase I clinical results were announced.[5] Phase 1b results have also been reported.[3][2]
As of December 2016[update] it was in two phase 2/3 clinical trials that have progressed to phase 3.[1][6][7] EPOCH, was to complete data collection for the primary outcome measure by June 2017.[7] However, in February 2017 Merck halted its late-stage trial of verubecestat for mild to moderate Alzheimer's disease after it was reported as having "virtually no chance of finding a positive clinical effect" according to an independent panel of experts.[8] The results of Merck's trial of verubecestat on patients with prodromal (early stage) Alzheimer's were expected in February 2019. However, the trial was terminated in February 2018, after a data monitoring committee concluded it was unlikely that the drug would show a positive benefit/risk ratio.[9][10] The final conclusion was that "verubecestat did not reduce cognitive or functional decline in patients with mild-to-moderate Alzheimer’s disease and was associated with treatment-related adverse events". Verubecestat was projected to be a breakthrough medicine for dementia related illness, however it is still unknown why the medicine was not effective in humans. [11]
^Clinical trial number NCT01953601 for "Efficacy and safety trial of verubecestat (MK-8931) in participants with prodromal Alzheimer's disease (MK-8931-019) (APECS)" at ClinicalTrials.gov
^ abClinical trial number NCT01739348 for "An efficacy and safety trial of verubecestat (MK-8931) in mild to moderate Alzheimer's disease (P07738) (EPOCH)" at ClinicalTrials.gov
^Clinical trial number NCT01953601 for "Efficacy and Safety Trial of Verubecestat (MK-8931) in Participants With Prodromal Alzheimer's Disease (MK-8931-019)" at ClinicalTrials.gov