The scientific rationale for the use of K40 for treatment of SD was based on clinical evidence that K40 improves erythema and desquamation with mild adverse reactions in a few cases. The primary objective of the study was to evaluate the efficacy of K40 (K40a and K40b combined) compared to placebo after 4 weeks treatment as measured by the sum of erythema and desquamation scores at Week 4.