Hi, Allie! I was on Tecvayli (Teclistamab) for about six weeks. It was part of my bridging therapy for my CAR-T therapy transplant. That's the time between when they harvest your T cells, and when you get them back. I didn't have any really bad side effects. I remember being tired, but my cancer load was very high at the time. My Dr said my T cells were too weak to fight, so I'm not sure how effective it was for me. They never took my myeloma labs ahead of my transplant. For that reason I'm not sure how well it did. It is supposed to work really fast though. It's acts like CAR-T, but it's considered an "off the shelf" med, since your not using your own cells and there isn't a wait time. It's a weekly shot, whereas CAR-T is once and done. You do have to be in the hospital for observation one week at the start, while they give you "step up" doses starting with 1/3 dose, then 2/3 and then full dose all given two days apart. I had no side effects, and was able to get the full dose once a week from there on. BTW, my CAR-T transplant (6/23) worked it's wonders and still is at this point. 💙