Why is this phase needed? There are two principal reasons why this phase is needed. One way of “proving” that ICS modifies serum CRP levels is to demonstrate that withdrawal of ICS increases CRP levels and their re-introduction of ICS suppresses CRP levels. The Second reason is that in the researchers' pilot study it was found that serum CRP levels were highest when patients were off ICS for 4 weeks. To achieve the necessary statistical power for this study, a reasonably high serum CRP signal is desirable at the beginning of the randomization period.