2013年10月29日讯 /生物谷BIOON/ --默沙东公司研发的治疗心脏病药物anacetrapib被认为是研发过程最昂贵、最困难的研究计划之一，而一旦研究成功，这种药物又将跻身成为利润最高的药物行列。然而一些分析人士认为这种药物的研发风险相当高并因而常常拒绝估计其潜在市场。最近研究表明，这种药物在体内驻留时间极长，在患者停用药物的三个月后，体内仍然可以检测到40%的药物水平。
Merck's ($MRK) experimental anacetrapib is one of those massively expensive lottery programs that can spur dreams of huge revenue streams. But the risks are so extraordinary that top analysts often refuse to even speculate on a peak sales estimate. And now there's a new risk element to the drug that is spurring some fresh concern about its prospects in the clinic.
Forbes' veteran pharma scribe Matthew Herper picked up on a report in the American Journal of Cardiology covering a study which demonstrated that the drug has a remarkable ability to linger in the system long after patients stop taking it. Three months after they stopped taking the drug daily, anacetrapib was found at a level of 40%. In 30 patients, the drug was detectable four years after they stopped taking the cholesterol medicine.
Merck is running a huge study on this drug that won't read out until 2017. But after Pfizer ($PFE) and Roche ($RHHBY) tried and failed with their own CETP programs for cholesterol--torcetrapib and dalcetrapib, also designed to boost HDL and reduce the risk of cardiovascular events--there's a significant amount of skepticism that Merck can succeed after those ambitious efforts collapsed. And if the drug is linked to any adverse events, evidence that it lingers in the system would inevitably raise serious concerns among regulators about the potential risk for a large patient population--reducing the chances of an approval.
Herper gets both sides of the issue in his story.
"It is always an issue if the drug hangs around to cause potential adverse safety events," Sanjay Kaul, director of the Vascular Physiology and Thrombosis Research Laboratory at the Burns and Allen Research Institute at Cedars-Sinai Medical Center, tells Herper.
"A drug would have to be known to be incredibly safe before you would be willing to have it hang around in your body for years," notes Harlan Krumholz, the Harold H. Hines Jr. Professor of Medicine at Yale Medical School and a Forbes contributor.
On the other hand:
"If the drug turns out to have significant benefits in reducing CV events and has a satisfactory safety profile this wouldn't keep it from being accepted or approved," Antonio M. Gotto, the dean emeritus at Weill Medical College of Cornell University and the lead investigator of the Merck study, tells Forbes.
Merck says the data aren't causing any internal fretting about the drug's commercial or regulatory prospects.
"It would be premature to speculate on any potential regulatory/commercial implications that may arise from the results of this small substudy," a company spokesperson tells FierceBiotech. "As you know, the clinical program for anacetrapib is proceeding."
Merck was essentially forced into announcing a major reorganization of its R&D division after experiencing a litany of setbacks in its late-stage pipeline. Finding another cloud drifting over a high-risk, Hail Mary R&D program will just create more unease among investors looking for some reassurance that the company can get back on track and successfully develop new products to help fight back against an onslaught of generic competition. It also could add some collateral damage for Eli Lilly ($LLY), which has its own CETP effort still in the pipeline--and faces its own chorus of R&D critics.