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Prednisone therapy is the most successful method of GCA management available today (2007). Because long-term use of high doses can produce undesirable side effects various steroid-sparing options have been used in trials or in isolated cases. Two were tried with Pearl but were only partially successful if at all. Some present high risks of severe infection or organ damage, another increases risk of blindness. At this time there are no promising steroid-sparing medications available for GCA patients. The hope is that research will provide an alternative to prednisone in the future. Appendix 10 has a bibliography of steroid-sparing medical journal articles that may be of interest. Some current steroid-sparing medications or therapies are described:
Alternate day prednisone therapy with or without methotrexate
This concept can consist of no treatment on the alternate day, or a reduced amount of prednisone on the alternate day. It usually is attempted in conjunction with another medication, like methotrexate.
A major study was made of no treatment on alternate days in combination with methotrexate. It demonstrated no success; unfortunately 11 % of the participants lost vision in at least one eye in the study.
Other studies have shown that GCA was obviously untreated on the alternate day - symptoms were evident on the alternate days.
In 2005 Pearl tried a reduced amount of prednisone on alternate days in combination with methotrexate. Her prednisone doses were 12 mg, then 8 mg, then 12 mg, etc. She found that on the low prednisone day she was undertreated so after four months the treatment was changed back to normal dosage every day. Methotrexate was discontinued because of the stomach pain either it or folic acid supplements caused and it appeared to be ineffective. Methotrexate was tried twice simply as an adjunct medication to prednisone – this was described in Chapter 5.
Aspirin
Aspirin has anti-inflammatory properties so it is recommended by some, especially when arteries are inflamed. Pearl was allergic to aspirin so it was never a consideration for her.
Infliximab
A major study was made based on Infliximab therapy in 2004 – it was stopped at the mid-point because of lack of efficacy.
Etanercept, azathioprine, cyclophosphamide, dapsone, adalimumab and rituximab
Each of these medications has shown promise as an alternative or adjunctive medication to prednisone on a small population basis. One is usually tried if prednisone isn’t effective at reasonable dose levels. Success has been reported as well as failures. These are considered to be high risk medications having the potential for serious side effects. An example is this observation extracted from one of the articles concerning rituximab: "We describe a patient with polymyalgia rheumatica/giant cell arteritis (PMR/GCA) whose disease was refractory to a reduction in the dose of her glucocorticoid to an acceptable level. Our patient improved after B lymphocyte depletion but developed respiratory problems."
Imatinib mesylate
Research has been reported that Imatinib-mesylate may offer therapeutic potential to limit vascular occlusion and ischemic complications in large-vessel vasculitis. This is a recent study – it is not a currently viable treatment for GCA but might be promising for the future.