Clearly frustrated by the U.S. FDA’s rejection of tradipitant to treat gastroparesis, Vanda Pharmaceuticals Inc. CEO Mihael Polymeropoulos said the agency is discouraging drug development for the serious gastric emptying condition for which there has been no new treatment in 40 years. The complete response letter (CRL) issued on the Sept. 18 PDUFA date for the neurokinin-1 receptor antagonist, which Vanda licensed from Eli Lilly and Co. in 2012, requested additional studies that the company said are not in line with the advice of experts in the field.