A regular anti-virus isn't going to remove it completely for you. It's takes some work to completely remove it from your system. www.malwarebytes.org will help and then Spybot....www.safer-networking.org Then follow the steps on one of these sites without downloading their tools and you'll get rid of it. Those two cleaners are free downloads and will prevent your system from getting those trojans. They take time and patience to remove.
How to Remove JS/DwnLdr-MON Trojan - Remove Spyware ...
www.howto-uninstall.com/remove-jsdwnldr-mon-trojan-how-to-remove