Wednesday, May 20, 2015

Medical research is hard - two NYT articles on Losartan for Marfan syndrome.

In 2013 the NYT’s Gina Kolata was optimistic about using Losartan, an angiotensin II receptor blocker (ARB), to treat Marfan’s syndrome …

… He sought a way to block the function of T.G.F.-beta and found a widely used blood pressure drug, losartan, that did just that.

In the mice, the drug prevented features of the syndrome, including ballooning of the aorta. Instead of dying of aortic aneurysms by three months of age, the mice lived a normal life span of two years…

… The Specks enrolled Daniel, and suspect he got losartan. His mother said the family saw “wonderful changes — everything started to stabilize.” Daniel’s aorta had been “growing astronomically,” she said, and that growth slowed so much that he would not qualify if he tried to enter the trial today. He also developed better muscle tone and more body fat.

When his time in the trial ended, the Specks were told Daniel could take losartan or the older drug, whichever they preferred. Ms. Speck did not want to take any chances. They chose both…

The human trial wasn’t finished at the time of publication but everyone was optimistic.

A year later Ms. Kolata wrote a followup article…

Heart Drug, Losartan, Falls Short of Promise in a Study - NYTimes.com

The idea seemed compelling: A blood pressure drug was found to block the effects of a gene mutation that causes Marfan syndrome, a condition that leads to terrible heart problems. The drug worked in mice with a gene that causes Marfan, doing just what everyone hoped it would do. A pilot study with 17 children showed the drug seemed to work in them, too, although there was no group that, for comparison, did not get the drug.

Now the more objective human evidence is in — results from a large clinical trial testing the experimental drug against the standard treatment. There was no difference in outcomes

The standard treatment is a beta blocker - atenolol. It’s thought both drugs work better than placebo, so losartan isn’t necessarily ineffective, it just doesn’t seem to work as well in humans as it does in genetically modified mice.

Medical research is hard.

PS. I found the 2013 Losartan ref in my Pinboard share stream, specifically, in an accidentally untagged portion the stream I was reviewing. Seeing it I wondered if there was a followup article….

 

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