Duvelisib, whose commercial name is Copiktra, is a molecule that inhibits the delta and gamma isoforms of the PI3 Kinase (PI3K for phosphoinositide-3 kinase). Duvelisib has potential immunomodulatory and antineoplastic activities. Duvelisib inhibits activation of PI3K delta/gamma-mediated signalling pathways, which may result in reduced cell proliferation in tumour cells expressing PI3K delta/gamma. Unlike other PI3K isoforms, delta and gamma isoforms are overexpressed primarily in hematologic malignancies and inflammatory and autoimmune diseases. By selectively targeting these PI3K isoforms, PI3K signaling in normal non-neoplastic cells is little or not affected, resulting in a more favourable side effect profile. Duvelisib is used in the treatment of chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL).

The excessively high mortality rates of severe and critical cases of COVID-19 warrant the identification and evaluation of new therapies that could potentially mitigate the advanced manifestations of the disease. Based on preclinical data, the researchers hypothesize that inhibition of PI3K by duvelisib could potentially suppress aberrant overactivation of the innate immune system, preferentially polarize macrophages, reduce lung inflammation and limit viral persistence, thereby improving patient outcomes.