The present invention provides novel therapeutic applications of low dose naltrexone (LDN). Said applications have been determined in light of the discovery by the present inventors that naltrexone acts as an antagonist of Toll-like receptor 9 (TLR9), an innate immune receptor which elicits the production of inflammatory cytokines when agonised. Chronic inflammation and TLR9 overexpression are characteristics of a number of disorders, including certain cancers. Accordingly, the present invention provides novel uses of naltrexone in the treatment of a subject having a disorder characterised by TLR9 overexpression and/or overactivity of TLR9-mediated signalling. The present invention also provides novel uses of naltrexone in the supportive care of subject having a tumour/cancer, and methods of treating and providing supportive care to a subject, comprising the administration of naltrexone.
