Abstract: The invention relates to the use of an inhibitor of the dihydrofolate reductase enzyme selected from the group that consists of methotrexate, trimetrexate and pemetrexed; or a pharmaceutically acceptable salt thereof, for the preparation of a drug for the treatment or prevention of recurrences of a disease selected from the group that consists of cancer, psoriasis, psoriatic arthritis, juvenile polyarticular arthritis, rheumatoid arthritis, Crohn's disease, polymyositis, dermatomyositis and sarcoidosis, wherein said treatment or prevention includes administering to a patient, simultaneously, separately or sequentially, a lipophilic statin and the inhibitor of the dihydrofolate reductase enzyme. The invention also relates to a pharmaceutical composition which includes the inhibitor of the dihydrofolate reductase enzyme and the lipophilic statin together with pharmaceutically acceptable carriers and/or vehicles.