Adobe Reader OCX use in Windows 10 64 bit

I have a Delphi application which uses the Adobe Reader Active X component.  When compiled to a Windows 32 target it works perfectly, but when compiled to Windows 64 target I am unable to display any PDF files, I just get the dark grey background.  I am using Delphi 10.1 Berlin.  Can anyone advise on what I should do to overcome this?