On a disease sexiness scale from 0-100, chronic idiopathic constipation (CIC) and irritable bowel syndrome (IBS-c) are close to rounding out the bottom of that range. However, they remain important medical problems.
CIC accounts for roughly 6 million related outpatient visits each year and just over a quarter million hospital admissions with constipation as the primary diagnosis. In addition, an estimated 12 million Americans suffer from IBS-c and many have symptoms for a decade. Since the withdrawal of the 5-HT4 agonist, Zelnorm (tegaserod), by Novartis (NVS) in March of last year due to possible heart risks, there has been no approved therapy for IBS-c.
Amitiza (lubiprostone), from Sucampo (SCMP) and Takeda (TKPHF.PK), a chloride channel activator that works in the small bowel and has already been approved by the FDA for CIC, yesterday was approved for the treatment of IBS-c. The drugs is safe (though does have an adverse event [AE] nausea rate of ~30%), effective, and most importantly from a safety standpoint, is not absorbed.
It has always puzzled me why its sales have lagged behind expectations (only $48m in ‘06 and $154m in ‘06). I’ve always assumed the reason was the AE nausea combined with a slow marketing ramp-up and hoped that it wasn’t that physicians were scared away from prescribing therapies after the Zelnorm fiasco (I generally give physicians more credit than that).
Since Zelnorm was only approved to treat IBS-c, the sales numbers, until now, weren’t directly comparable, but I’m interested in seeing the year-end increase in sales to tease out the meaning behind the initially poor revenues. In its final year, Zelnorm sold almost $500m and was well on its way of surpassing that mark before being killed; I would expect the numbers for Amitiza in the next few years to be higher than that.
I think Sucampo (which will also received a $50m milestone payment from Takeda, which holds the US rights) has a winner in Amitiza and so far, the market agrees. SCMP was up 38% (to 16.75) after an hour of trading on this morning's market.