The US FDA has approved orphan drug Kynamro (mipomersen sodium) injection for the treatment of homozygous familial hypercholesterolemia (HoFH), an inherited cholesterol disorder.

Kynamro, manufactured by Genzyme, was approved as an adjunct to lipid-lowering medications and diet for patients with HoFH.

The drug was developed to reduce low-density lipoprotein-cholesterol (LDL-C), apolipoprotein B, total cholesterol, and non-high density lipoprotein-cholesterol (non HDL-C).

The FDA’s Center for Drug Evaluation and Research, metabolism and endocrinology products division deputy director Dr Eric Colman said; "Kynamro, an injection given once a week, works with other lipid-lowering medications and diet to impair the creation of the lipid particles that ultimately give rise to LDL-C."

Kynamro established its safety and efficacy profile in a trial conducted in 51 HoFH patients, demonstrating an average reduction of LDL-C by around 25%.

Common adverse reactions associated with the study drug included injection site reactions, flu-like symptoms, nausea, headache and elevations in liver enzymes.

These elevations have resulted in Kynamro carrying a Boxed Warning on the serious risk of liver toxicity.

Four post marketing studies fare still required by the FDA, which include the development of a sensitive assay that binds double-stranded (ds) DNA; a study assessing antibody presence to ds-DNA in Kynamro treated patients; a long-term registry of HoFH patients to conclude Kynamro’s long-term safety and a better pharmacovigilance programme.

Image: Kynamro manufacturer Genzyme’s global headquarters in Cambridge, Massachusetts, the US. Photo: Courtesy of Tim Pierce.