Drugs interaction - ICI like Keytruda, Opdivo, Tecentriq and other PD-1/PD-L1 blocking drugs and steroids

[Olga]

Steroids are the first line of defense when the drug induced or disease induced toxicities/side effects are managed - corticosteroids are typically used to reduce a swelling and an inflammation in emergency type of situation, for example with the immunotherapy caused autoimmune conditions as colitis, Hepatitis, miocarditis or autoimmune diabetes mellitus. While managing the side effects, they potentially decrease efficacy of immunotherapy, abrogating the effect of the treatment - while the immune system is unblocked by the PD-l/PD-L1 targeting drugs, the immune system itself is blocked by the steroids...
There is a need to reduce the duration/dose as possible, and to avoid using steroids when possible in managing other treatments side effects or to separate them - i.e. if you need to treat the brain metastasis by the radiosurgery and it is rather big with the higher risk of the brain swelling after the treatment, consider having a treatment and the recovery period first and starting immune checkpoint inhibitor later.
This article discusses the understanding of the strategy for now
Corticosteroids for the management of immune-related adverse events in patients receiving checkpoint inhibitors.
https://www.ncbi.nlm.nih.gov/pubmed/29224458
And at least if you have to take steroids while receiving checkpoint inhibitors and the drug does not work, discuss with the oncologist that its action might have been blocked and this failure should not be a reason for stopping checkpoint inhibitor, there is a reason to give it more try after steroids are done with.