Yes, underlying all these manifestations is inflammation. Tumor Necrosis Factor is a cytokine which when it binds to tissues creates inflammation. The benefit as the name suggests is to prevent the migration of tumor cells into tissues, however, after years of autopsies which revealed that TNF was present at very high levels in people with arthritis, the search was on for a solution.
Concomitant to these studies was the United States sponsorship of "orphan drugs", ones which attempted to respond to suffering of it's citizens. I'm sure the business relationships are complicated however Johnson and Johnson created a new division Centocor https://www.pharmaceutical-technology.com/projects/centocor/
which over many years developed a medication designed to respond to Crohn's Disease and the suffering it caused. Centocor conducted trials of Infliximab (Remicade) in Europe over ten years.with startling success. The FDA approved it for treatment of Crohn's and it did not take long for it to be tested for Rheumatoid then AS and onward.
The story is legendary in the creation of a gazillion $ blockbuster drug and a medication which alleviates the suffering of millions world wide.
I am really pleased to hear how intimately connected you are in your hospital, there is a certain trust which develops and can be a real benefit for you as you seek answers. Safety, efficacy and results are the hallmark of starting a new medication. Best of luck to you.