Merck cholesterol scrips drop as Niaspan rises

Last week, all eyes were on Merck's cholesterol drugs. How did Zetia do in that much-anticipated study pitting it against Abbott Laboratories' Niaspan treatment? Well, the American Heart Association meeting has come and gone, and while the study favored Niaspan, the even-handed media coverage pointed out the trial's shortcomings as well as its top-line results. Analysts and investors appeared relieved.

But one big question remained: How would doctors and patients react in the real world? Now we have that answer: They pulled back from the Merck meds. Both Zetia and the Zocor-Zetia combo drug Vytorin suffered last week, with Zetia scrips dropping by 8.5 percent week over week to 151,100 and Vytorin declining 5.2 percent to about 163,600, Dow Jones reports. Meanwhile, scrips for the Abbott drug grew. Total Niaspan prescriptions rose by 2.6 percent week over week to 107,360.

"There's a lot of switching taking place," Timothy McGee of the SDI market research firm told Dow Jones. And SDI pointed to two stats that even more clearly indicate that last week's study debut changed people's minds. Niaspan scrips among new patients who weren't using cholesterol meds over the previous 12 months rose 33.8 percent week over week, while Zetia scrips among those patients dropped 24 percent and Vytorin scrips fell 16.8 percent. Among patients with new scrips who had used cholesterol meds in the past year, the difference was even more marked: Up 45.6 percent for Niaspan; down 27.4 percent and 23.7 percent for Zetia and Vytorin.

Merck downplayed the scrip data, saying that it's too soon to gauge just how the Arbiter study will affect prescription trends. So stay tuned; new data comes out every week.

- read the Dow Jones piece