I found a single vaccine trial that a) is still recruiting and b) does not exclude brain mets:
https://clinicaltrials.gov/ct2/show/...accine&rank=17
You might want to sign up at:
https://www.breastcancertrials.org/bct_nation/home.seam
After you complete a profile, they'll send you notifications. A cautionary note on that, though. I am early stage, but I wanted very much to contribute to research, so I nagged my oncologist about trials. She was useless, so I found one on my own. The trial I'm enrolled in is listed at Breast Cancer Trials, but it was never included in the trials they offered to me. I wrote to them about the omission, and they claim to have made some changes to their algorithm. I think it pays, however, to search the site anyway.
I also think it may be useful to pick some hospitals that interest you and look at their local trial site listings. My former cancer center had a number of trials that I did not find listed at clinicaltrials.gov. I'm a bit boggled by that, but if they're doing it, others may be doing it as well.
Another site that might be helpful is:
https://medivizor.com/
They send notifications of relevant studies and trials. It's another profile to complete, but after you've done a few, it doesn't take quite so long.
The Army of Women sends out notices of trials, but I've not seen any that would be relevant to your situation. Nonetheless, you might want to consider it one day when you feel like filling out yet another questionnaire.