Their mechanism of action is not entirely clear, but it is known that they inhibit the production of tumour necrosis factor, interleukin 6 and immunoglobulin G and VEGF (which leads to its anti-angiogenic effects), co-stimulates T cells and NK cells and increases interferon gamma and interleukin 2 production. Their teratogenic effects appear to be mediated by binding to cereblon.
Thalidomide and its analogs, lenalidomide and pomalidomide, are believed to act in a similar fashion even though their exact mechanism of action is not yet fully understood. It is believed that they work through different mechanisms in various diseases. The net effect is probably due to different mechanisms combined. Mechanism of action will be explained in light of today's knowledge.