Why in the world would 2 pharmaceutical manufacturers bring out 2 different drugs at about the same time to compete with each other to treat a disease that only affects 300 people in the US? In the absence of inside information, of which I have none, I would guess that they will try to find a way to treat some other people as well.
The disease is homozygous familial hypercholesterolemia, which occurs once in every million births. Affected patients run serum cholesterol levels that can go to 600 mg/dL or higher and develop severe arteriosclerosis in childhood. Before cholesterol-lowering treatments became available, they usually died of heart disease when they were teenagers. Now, with vigorous treatment including lipid apheresis, they generally survive into their early thirties.
The 2 new drugs, lomitapide (Juxtapid) and mipomersen (Kynamro), which we will review in the April 1 issue of The Medical Letter, were both approved by the FDA for use only in these patients, and only when maximal lipid-lowering therapy (statins, ezetimibe, bile-acid sequestrants, niacin) had failed either to lower cholesterol to an acceptable level or to be tolerable. The new drugs would, hopefully, make it possible for patients with this rare disorder to avoid the unpleasantness of lipid apheresis.
Neither of the 2 new drugs is a statin, and both have demonstrated that they can lower serum cholesterol levels substantially. That being so, might we see some bracket-creep in the direction of other patients with high cholesterol levels that have not responded adequately to statins? I am sure the manufacturers hope so. Heterozygous familial hypercholesterolemia occurs once in every 50 births, and some hypercholesterolemic patients with no detectable genetic disorder cannot tolerate or do not respond adequately to statins. If the patients with homozygous hypercholesterolemia do well, the pressure will grow on the FDA to approve these agents for broader indications.
How effective are they? How safe? And, you should ask, what do they cost? For all that and more, watch for the April 1 issue of The Medical Letter.