Invesco Perpetual has decided not to hire a replacement for Drew, who is leaving without a job to go to.
Drew told PRWeek she had finished the task she had joined Invesco Perpetual to undertake and was looking for a 'wider role'.
Invesco Perpetual PR manager Jane Bland, who continues to handle the group's external relations for its retail funds from Oxfordshire, will be promoted to head of PR on Drew's exit and will be Invesco Perpetual's most senior PRO.
But the changes will cut Invesco's external comms team from three to two with no full-time PRO in London.
Drew said Invesco Perpetual would not be reviewing its relationships with Lansons Communications, which handles its financial services PR, or public affairs firm Cicero Consulting.
Drew joined Invesco Perpetual as head of corporate comms in 2001 shortly after the firm's creation through Invesco parent Amvescap's acquisition of the Henley-based Perpetual.
She had previously spent three years as head of corporate communications at Charles Schwab Europe. She joined the brokerage firm in 1999 as head of European public affairs and communications from Fidelity Investments, which is now the UK's largest manager of retail funds.
Drew worked at Fidelity for two years as head of media relations for Europe, prior to which she spent ten years at American Express, where she was most recently director of public affairs, Europe.
Invesco Perpetual hit the news last week when the firm's investment trust, Perpetual Income & Growth (PIGIT), launched a hostile bid for Securities Trust of Scotland (PRWeek, 11 March).
An online poll for Money Marketing last month found that 81 per cent of independent financial advisers felt that Invesco Perpetual was right to bring back the mountain used in Perpetual's advertising, while 66 per cent felt the company should reintroduce Perpetual as a standalone brand.