Prednisone dosage for the PR is a major concern. Initial dosages can be 20 mg daily, decreased 50% at 21 weeks. The accumulative dose is dangerous for osteoporosis, weight gain, hypertension and heart disease. Methotrexate at 7.5 mg weekly failed to reduce this accumulative dose though 10 mg did help. Now Etanercept (Enbrel) shows useful promise.
Arthritis Rheum. 2007 Dec 15;57(8):1514-9.
Treatment of refractory polymyalgia rheumatica with etanercept: an open pilot study. Catanoso MG, Macchioni P, Boiardi L, Pipitone N, Salvarani C. abstract
- Included a subgroup that were not able to get their dosage below 7.5-10 mg
- 6 cases – open pilot study
- Etanercept 25 twice weekly for 24 weeks
- “A significant reduction in the cumulative prednisone dose 9 months before versus the 9-month study period was observed (mean +/- SD 1,767 +/- 524 mg versus 730 +/- 182 mg; P = 0.028).”
- “Three patients developed nonsevere side effects: bacterial cystitis in 2 and influenza in 1”
- “These results, which should be confirmed in a controlled study, suggest that etanercept may be a safe and useful corticosteroid-sparing agent in relapsing PMR.”
A related drug, infliximab (Remicade) failed to help and was considered to potentially worsen the situation:
Ann Intern Med. 2007 May 1;146(9):631-9. Comment in: Ann Intern Med. 2007 May 1;146(9):674-6. Ann Intern Med. 2008 Jan 15;148(2):166; author reply 166. Summary for patients in: Ann Intern Med. 2007 May 1;146(9):I20. Infliximab plus prednisone or placebo plus prednisone for the initial treatment of polymyalgia rheumatica: a randomized trial. Salvarani C, Macchioni P, Manzini C, Paolazzi G, Trotta A, Manganelli P, Cimmino M, Gerli R, Catanoso MG, Boiardi L, Cantini F, Klersy C, Hunder GG.
“Although too small to be definitive, the trial provides evidence that adding infliximab to prednisone for treating newly diagnosed polymyalgia rheumatica is of no benefit and may be harmful. If there is benefit, it is unlikely to be large.”
A previous study with metotrexate using 7.5 mg weekly failed to decrease prednisone needs:
However 10 mg Methotrexate weekly did have some effect:
Ann Intern Med. 2004 Oct 5;141(7):493-500. Comment in: Ann Intern Med. 2004 Oct 5;141(7):568-9. Summary for patients in: Ann Intern Med. 2004 Oct 5;141(7):I12. Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial. Caporali R, Cimmino MA, Ferraccioli G, Gerli R, Klersy C, Salvarani C, Montecucco C; Systemic Vasculitis Study Group of the Italian Society for Rheumatology abstract
- “Twenty-eight of 32 patients in the methotrexate group and 16 of 30 patients in the placebo group were no longer taking prednisone at 76 weeks (P = 0.003).”
- “Fifteen of 32 patients in the methotrexate group and 22 of 30 patients in the placebo group had at least 1 flare-up by the end of follow-up (P = 0.04). The median prednisone dose was 2.1 g in the methotrexate group and 2.97 g in the placebo group (P = 0.03). The rate and severity of adverse events were similar. “
- “Prednisone plus methotrexate is associated with shorter prednisone treatment and steroid sparing. It may be useful in patients at high risk for steroid-related toxicity.”
Comment – in treatment resistant cases, it looks like the addition of methotrexate10 mg (but not 7.5 mg) is beneficial. It reduces prednisone requirements by 29%. Etanercept reduced it by 59%. However each shot is $200.00 and that would come to over $10,000.00 for the 24 week course. Methotrexate is used in cancer chemotherapy and can cause nerve damage neuropathy. Though etanercept has been helpful in occasional neuropathies: link, it can rarely cause optic neuropathy abstract and a reported case of peripheral neuropathy:link
Infections are risks with both treatments.