At the beginning of this month of June, the Food and Drug Administration (FDA) announced its decision to grant marketing authorisation to the monoclonal antibody aducanumab, the first treatment option targeting and affecting the underlying disease process of Alzheimer’s disease, according to the press release of the medicines regulatory agency of the USA.1 What should have been a source of joy and recognition of the success of basic and clinical sciences, however, resulted in a bitter dispute in the scientific community, that ended up in the resignation of three of the experts who had participated in the committee that advised the agency on the safety and efficacy of this new drug.2

The reasons behind this controversy are worthwhile visiting, by those interested in the role of evidence-based medicine in the design of public policies. The approval of aducanumab by the FDA was obtained through an expedited approval mechanism, aimed at easing patient access to breakthrough drugs, either potentially life-saving or targeting disabling diseases with no available therapy. This ‘accelerated approval’ mechanism allows the authorisation of medicines on the basis of fewer, smaller and less rigorous methodological designs, including the use of surrogate measures such as biomarkers that are only ‘reasonably likely’ to predict meaningful clinical benefit …