I'm not a prednisone advocate but have taken it for 2 occurrences of PMR (3-1/2 years and 1-1/2 years) with no issues other that weight gain. I haven't taken Actemra but would have to discuss it with my doctor and weigh the risks both ways.

Just an fyi...
"Actemra has a boxed warning for risk of serious infections. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). Actemra may cause serious infections such as tuberculosis (TB). Some infections from Actemra may be serious enough to require a hospital stay."
--- Actemra Side Effects: What They Are and How to Manage Them: https://www.healthline.com/health/drugs/actemra-side-effects