The Whitehall-based body has yet to decide how he will be replaced.
Hayes - one of the best-known figures in pharma communications - has taken the role of comms head at North Yorkshire County Council in February. He has spent more than 15 years with the ABPI and has been director of public affairs for more than a decade.
During Hayes's time at the ABPI, scrutiny of the drugs industry has increased significantly in the wake of numerous scandals. The ABPI has taken measures to improve transparency - it tightened up the industry's Code of Practice in January and launched a policy of ‘shaming' bad practice.
Hayes has been instrumental in ABPI campaigns for greater take-up of new medicines in the NHS and extra government investment in the pharma industry.
At North Yorks he will replace Claire Walker, who left two months ago, in charge of a nine-strong team. Hayes started his career on the Hackney Gazette and other East London papers.
At the ABPI he heads a comms and PA team of ten.