A drug that has been used to treat rheumatoid arthritis may find a new niche in treating blood cancers at a fraction of the cost, according to British researchers.
According to an article in Futurity.org, myeloproliferative neoplasms (MPNs) cause an overproduction of blood cells resulting in symptoms that include night sweats, itching, and tiredness. Usually occurring in people in their 50s and 60s, MPNs are currently treated with aspirin, removal of excess blood and mild chemotherapy. A new drug, Ruxolitinib, is effective, but it costs more than $62,370 per patient per year and has yet to be approved by the National Institute for Health and Care Excellence (NICE) (http://www.futurity.org/methotrexate-blood-cancers-953662/?utm_source=feedly&utm_medium=webfeeds).
Martin Zeidler of the biomedical science department at University of Sheffield and his colleagues think they have a better answer. In a study funded by Cancer Research UK and published in PLOS ONE, they show that Methotrexate (MTX) can work in the same way. Using cells from the fruit fly Drosophila, they screened for small molecules that suppress the signaling pathway central to the development of MPNs in humans. After further testing, they confirmed this in human cells, "even those carrying the mutated gene responsible for MPNs in patients."
According to Zeidler, "Given that a year's course of low-dose MTX costs around £30 [$47], the potential to repurpose MTX could provide thousands of patients with a much needed treatment option and also generate substantial savings for health care systems. Because MTX is a World Health Organization ‘essential medicine,' this also means that this well understood drug could be used throughout the developing world."
Zeidler explains that MTX can be used at low doses to treat inflammatory diseases including rheumatoid arthritis, Crohn's disease and psoriasis and has few side effects and that it is also used in some cancers at much higher doses where the side effects are substantial and similar to other chemotherapies. Now working with clinical colleagues at the Royal Hallamshire Hospital, he is attempting to do clinical trials to examine the possibility of repurposing low-dose MTX for the treatment of MPNs.
As Zeidler says, "We have the potential to revolutionize the treatment of this group of chronic diseases-a breakthrough that may ultimately represent a new treatment option able to bring relief to both patients and health funders."
According to Nell Barrie, senior science information manager at Cancer Research UK, "Finding new uses for existing drugs is a great way to speed up improvements in treatment, as these drugs will have previously been through safety tests. Methotrexate is already used as a chemotherapy drug for several types of cancer, and this early research shows that at much lower doses it could have the potential to help treat certain blood disorders."
As explained by the Mayo Clinic, "Methotrexate belongs to the group of medicines known as antineoplastics (cancer medicines). It blocks an enzyme that is needed by cells to live. This interferes with the growth of cancer cells, which are eventually destroyed by the body. For patients with arthritis or psoriasis, methotrexate may work by improving the immune system." Methotrexate injection "is used alone or together with other medicines to treat several types of cancer," including breast, head and neck, lung, blood, bone, lymph node and uterine. It is also "used to treat adults with severe rheumatoid arthritis and children with polyarticular juvenile idiopathic arthritis who had other treatments that did not work well" and to control symptoms of severe psoriasis "in adults who have not been helped by other treatments" (http://www.mayoclinic.org/drugs-supplements/methotrexate-injection-route-subcutaneous-route/description/drg-20064776).
The Mayo Clinic also says, "Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems."