Drs. Morgan and Alarcón comment on the use of folic acid in our study. We chose a preparation (5-mg tablets) that was both commercially available and economical. Since the mean patient age was almost 80 years, we felt that adherence would be better with a daily protocol than with alternate-day regimens.

Spiera and colleagues mentioned the clinical importance of our results. While it was clear that combined treatment with methotrexate and prednisone resulted in lower relapse rates and lower doses of prednisone (the major outcomes of our study), we were not able to demonstrate a significant reduction in corticosteroid-related adverse events. We believe that this is because our sample size was calculated to demonstrate efficacy, based on preliminary data (1). A larger number of patients might be required to demonstrate a beneficial effect of our treatment protocol with regard to corticosteroid-related adverse events. This is likely to occur, given that corticosteroid-related adverse events depend on the cumulative doses and the duration of therapy (2) and that both are positively affected by methotrexate. Given the rarity of new-onset blindness after initiation of daily, high-dose corticosteroid therapy, we did not expect any cases of this particular outcome. Although an analysis of quality of life and functional outcomes might be relevant, nonspecific disease measurements are not widely used in clinical trials of such rare entities as giant-cell arteritis. To overcome the inherent lack of sensitivity of these kinds of tools, outcomes specific to giant-cell arteritis should be developed or adapted, but these objectives were beyond the goals of our study.

Our study demonstrated that combination therapy with methotrexate and prednisone is safe and more efficient than standard prednisone therapy alone. We believe that this presents new possibilities of treatment for patients with giant-cell arteritis and the opportunity to try to further decrease corticosteroid use.