People who take ACE inhibitors may develop angioedema, a condition that causes itchy and painful swelling beneath the skin around the eyes, lips, tongue, throat, hands, or feet. In severe cases, the throat may swell, obstructing the airway and leading to breathing difficulty. ACE inhibitors prevent the breakdown of a natural chemical in the body called bradykinin. Increased levels of bradykinin, which can cause swelling, may contribute to the development of angioedema. Blocking bradykinin receptor cells prevents bradykinin from initiating swelling and may lead to a possible decrease in angioedema symptoms. The purpose of this study is to evaluate the effectiveness of HOE-140, a bradykinin receptor blocker, at reducing symptoms in people with ACE inhibitor-associated angioedema.