U.S. regulators didn’t reject Map Pharmaceuticals Inc.’s inhalable migraine drug because of safety or effectiveness, and they don’t want new studies, Chief Executive Officer Tim Nelson said today. It was mostly about manufacturing issues, he told analysts on a conference call. Map, based in Mountain View, California, fell 4.1 percent to $16.44 at the close of trading in New York. The shares have gained 25 percent this year. Map’s Levadex is an inhaled form of dihydroergotamine, a 60-year-old migraine drug usually given by injection.