0000950123-04-005322 8-K 1 20040428 5 20040428 REGENERON PHARMACEUTICALS INC 0000872589 2834 133444607 NY 1231 8-K 34 000-19034 04760819 777 OLD SAW MILL RIVER RD TARRYTOWN NY 10591-6707 9143477000 8-K 1 y96770e8vk.htm REGENERON PHARMACEUTICALS, INC.