My endocrinologist advises staying on Prolia for life (for me). He also advises adding Evenity to the mix, but I'm resisting. After four injections, dexa shows improvement with just Prolia. I've had no perceivable side effects with Prolia. So far, my immune system seems to be holding up (no Covid, as far as I know). But like you, I have an over-active immune system. Mine presents with allergies and asthma. We're all guinea pigs in this experiment. Let's hope it works out.