The new study examined recent stretch marks and found that they had a higher density of hormone receptors than normal skin, and estrogen appeared to be the most concentrated. Since estrogen is involved in skin healing, that could represent the body’s attempt to heal the injured skin tissue. From the standpoint of steroid users, the greater number of estrogen receptors in stretch marks could also represent a defense against the high level of androgens, which interfere with skin healing. That latter part, however, is strictly speculation. What is known is that stretch marks have a higher density of hormone receptors than normal skin.
The presence of anti-natalizumab antibodies was correlated with a reduction in serum natalizumab levels. In Study MS1, the Week 12 pre-infusion mean natalizumab serum concentration in antibody-negative patients was 15 mcg/mL compared to mcg/mL in antibody-positive patients. Persistent antibody-positivity resulted in a substantial decrease in the effectiveness of TYSABRI. The risk of increased disability and the annualized relapse rate were similar in persistently antibody-positive TYSABRI-treated patients and patients who received placebo. A similar phenomenon was also observed in Study MS2.
Noninferiority trials have serious inherent limitations , the main one being that (unlike in a superiority trial), given a finding of noninferiority, it is impossible to distinguish between true equivalence and poor execution or faulty pretrial a priori assumptions regarding expectations of benefit and event rates. In this particular trial, a 15% absolute difference in the primary outcome was arguably too large to use as a noninferiority threshold. That threshold implies acceptance of 1 additional COPD exacerbation for each 7 patients treated. If a superiority trial showed a week's extra steroids prevented 1 COPD exacerbation for 10 or even 20 patients treated (, a 5-10% noninferiority margin), I think many doctors and patients would endorse longer-course prednisone. This trial (as designed) would fail to detect that.