Dealing with a toxic colleague.

How do you handle a toxic colleague who tries to take credit for your work and puts you down, never acknowledges genuine efforts, is very smug, throws in backhanded compliments and the words and actions don't align? This has come to a point where it's getting out of hand because they're doing it more often than not and now they've shared something that's very below the belt - an elaborate post on calling me a pretentious "bstrd". When confronted they're saying it's random? There are so many other instances that happened at work as well but I don't want to get into those. Let me just say they were all down bad and a new low - refusing to collaborate, always openly implying that they're the only one who's working when that's not the case. I find all this extremely unprofessional. Especially when we preach about core values and Integrity and 'Respect for Individual' so much? I've always been open to address any issues but I find this person almost always back biting other colleagues to me so I obviously wonder if they do the same about me to others. I find this extremely energy draining. But our role is one where we NEED to collaborate, can't even avoid the person. But this is getting overly toxic. Have any of you faced a similar colleague? How did you overcome this?