Lupus, an autoimmune disease, [recently] turned up on the front page of the Wall Street Journal (WSJ). It cropped up, also, on the first page of the New York Times business section, and elsewhere. Scientific American published a nice online review just now. The reason is that the FDA has approved a new monoclonal antibody for treatment of this condition.
The drug belimumab (Benlysta), targets a molecule called BlyS (B-lymphocyte Stimulator). The newspapers uniformly emphasize that this drug marks some sort of triumph for Human Genome Sciences, a biotech company that first reported on BlyS in the journal Science way back in 1999. BlyS triggers B cells to produce antibodies that in patients with lupus tend to bind and destroy their own cells’ needed machinery, causing various joint, lung, liver, kidney, brain, blood vessel and other sometimes life-threatening problems. So if and when Benlysta works, it probably does so by blocking aberrant autoimmune B-cell activity.
The newspapers don’t give a lot of details on the drug’s effectiveness, except that it appears to help roughly one in 11 patients, and the main benefit may be that some lupus patients on Benlysta can reduce their use of steroids, which have long-term and toxic effects on many organs. The most recent major medical publication on a trial on the drug came out in the Lancet two weeks ago.
Some reported caveats are that the drug has not been adequately tested or approved for patients with severe kidney or neurological manifestations of the disease, and that its activity, marginal as it is, appears to be less in patients of African heritage based on trials completed thus far. Additional trials are in the works.
The drug is expensive, to the updated tune of $35,000 per year. According to the WSJ: “Estimates of how many Americans are affected range from 161,000 to 1.5 million.” (How’s that for a wide ballpark figure? Likely a function of how hard it is to define and establish diagnosis for this disease, which anticipates how hard it will be to measure this drug’s effects — see below.) The same WSJ piece says analysts expect the drug to become a blockbuster, with annual sales eventually topping $1 billion. Read more »
*This blog post was originally published at Medical Lessons*