https://www.washingtonpost.com/health/2021/08/23/pfizer-vaccine-full-approval
The FDA now has fully authorized the Pfizer vaccine, which clears the way for big employers (eg the US military, other government orgs) to make it mandatory. Many such large organizations have already announced vaccine mandates. Data from Europe strongly suggests these mandates work to stop the spread of Delta, probably because they reduce the number of superspreaders who were taking few precautions.
Regeneron's monoclonal antibody cocktail is free and has recently become broadly available. It reduces risk of death from COVID by 70% if administered early in the infection (within a few days of symptoms showing up). It's a set of antibodies designed to tag the virus so that the immune system can find and destroy the virus more easily. I don't know for sure, but I'd guess its benefits probably stack with the benefits of vaccination in terms of preventing severe COVID cases, so if you catch a breakthrough case that seems to be getting worse, definitely ask your doctor about it. I'd also guess that anyone who is vaccinated but starts getting a more severe case of COVID probably has a relatively small number of naturally produced antibodies, either because of a weak immune system or because they were vaccinated a long time ago and those antibodies have declined. It will also help hospitals manage capacity because this will prevent a good fraction of unvaccinated COVID patients from ending up in the ICU.