Believed to be more than twice as good as anything already available a pill said to halt the devastating onset of Alzheimer's disease could be on the market within four years the Daily Mail reported. It could greatly slow or even halt the progression of the illness. Given early enough it could stop Alzheimer's from ever developing an international dementia conference told on Tuesday. A version of the twice-a-day pill developed by British scientists has already been tested on patients with ‘unprecedented’ results the Mail said. Its inventor Professor Claude Wischik of Aberdeen University said ‘It flat lines the disease.