Genzyme and Isis Pharmaceuticals say that a Phase III trial evaluating mipomersen in patients with heterozygous familial hypercholesterolemia (heFH) came up with positive results. The trial met its primary endpoint, with the mipomersen-treated cohort achieving a 28% reduction in LDL cholesterol after 26 weeks of treatment.
In contrast, LDL-cholesterol levels in the placebo-treated group rose by about 5%. Secondary endpoints were also met, with mipomersen therapy leading to significant reductions in apo-B, total cholesterol, and non-HDL cholesterol.
Positive data from a Phase III trial of mipomersen in homozygous FH (hoFH) was reported in November 2009. Genzyme notes that this will be the first indication for which it will seek marketing approval. Regulatory filings are expected to be made in the EU and U.S. during the first half of 2011.
These submissions may also include patients with severe hypercholesterolemia, the firm adds. A Phase III trial with mipomersen in this indication is due to report during mid-2010. Data from an ongoing Phase III trial in hypercholesterolemic patients at high risk of coronary heart disease is also expected in mid-2010.
Mipomersen is an apo-B synthesis inhibitor designed to reduce LDL cholesterol levels by preventing the formation of atherogenic lipids. In June 2008, Isis and Genzyme finalized their exclusive, worldwide license and collaboration agreement for the drug. As part of the deal, Isis earned a $175 million license fee and received a $150 million payment from Genzyme to purchase 5 million shares of Isis common stock at $30 per share.