Other than in a limited cases where multiple target interactions are synergistic and therapeutically advantageous, such as COX-2/5-LOX dual inhibitors for anti-inflammation [66] and AChE/BACE1 dual inhibitors for anti-AD [185], these multiple-target phenomena would potentially lead to off-target interactions and hence unwanted side effects and compromised potency. The gene discussed is BACE1; the disease is Alzheimer disease.