NEW YORK (AP) — Genzyme Corp. and Isis Pharmaceuticals Inc. on Wednesday reported successful trial results for mipomersen, as the companies said the cholesterol drug candidate met its primary goal in late stage clinical testing. Mipomersen reduced patients’ levels of LDL cholesterol, also called bad cholesterol, by 25 percent after six months, the companies said. Patients who received a dummy injection experienced a reduction of 3 percent. Genzyme, which is based in Cambridge, Mass., plans to ask the Food and Drug Administration for marketing approval late next year. That is about a year later than originally planned. The companies suffered a setback in early 2008, when regulators said they wanted to see preclinical study data before reviewing the application. The preclinical studies test whether mipomersen caused cancer. Those tests are still being conducted. In the trial, patients were injected with either 200 mg of mipomersen or a placebo once a week for 26 weeks. The patients have a condition called homozygous familial hypercholesterolemia, a genetic disorder that prevents them from properly metabolizing LDL cholesterol. Of the 34 patients treated with mipomersen, 28 finished the drug. The companies said one patient stopped because of elevated levels of a type of liver enzyme called transaminases. Other common side effects included reactions at the site of injection and flu-like symptoms. Full results from the trial will be presented at a future medical conference. Isis, which is based in Carlsbad, Calif., discovered the drug, and licensed it to Genzyme in January 2008.