Lenalidomide-I is primarily used in the treatment of multiple myeloma, a type of blood cancer affecting plasma cells. It is often prescribed in combination with other medications, such as dexamethasone, to enhance its efficacy. The drug works by modulating the immune system, inhibiting the growth of cancer cells, and promoting their apoptosis.

Additionally, it is utilized in managing myelodysplastic syndromes (MDS) with a specific genetic abnormality known as deletion 5q. In this context, it helps reduce the need for blood transfusions by improving blood cell production.

Lenalidomide-I is also employed in the treatment of certain types of non-Hodgkin lymphoma, including mantle cell lymphoma as maintenance therapy following stem cell transplantation, and relapsed or refractory follicular lymphoma and marginal zone lymphoma, typically in combination with rituximab.

Its immunomodulatory properties make it a valuable component in various therapeutic regimens for hematologic malignancies. Patients undergoing treatment with this drug require regular monitoring due to potential side effects, including increased risk of blood clots and lowered blood cell counts.