Prozac: No better than placebo?

A major new meta-analysis, as reported in The Guardian, makes exactly that claim. The full study, published in the Public Library of Science, is here. And, it’s not just Prozac; another major selective serotonin reuptake inhibitor antidepressant, Paxil, get the same critical nyet, as do two serotonin-norepinephrine reuptake inhibitor antidepressant:

The review breaks new ground because Kirsch and his colleagues have obtained for the first time what they believe is a full set of trial data for four antidepressants.

They requested the full data under freedom of information rules from the Food and Drug Administration, which licenses medicines in the US and requires all data when it makes a decision.

The pattern they saw from the trial results of fluoxetine (Prozac), paroxetine (Seroxat) [Paxil in the U.S.], venlafaxine (Effexor) and nefazodone (Serzone) was consistent.

“Using complete data sets (including unpublished data) and a substantially larger data set of this type than has been previously reported, we find the overall effect of new-generation antidepressant medication is below recommended criteria for clinical significance,” they write.

I think the conclusion is somewhat overstated, and meta-analysis research in general is sometimes overhyped; nonetheless, is this anywhere near bogus? I think the research probably is pretty solid.

In any case, Big Pharma is HUGELY worried and wasted no time to attack.

In adults, however, the depression-beating benefits were thought to outweigh the risks. Since its launch in the US in 1988, some 40 million people have taken Prozac, earning tens of billions of dollars for the manufacturer, Eli Lilly. Although the patent lapsed in 2001, fluoxetine continues to make the company money — it is now the active ingredient in Sarafem, a pill sold by Lilly for premenstrual syndrome.

Eli Lilly was defiant last night. “Extensive scientific and medical experience has demonstrated that fluoxetine is an effective antidepressant,” it said in a statement. “Since its discovery in 1972, fluoxetine has become one of the world's most-studied medicines. Lilly is proud of the difference fluoxetine has made to millions of people living with depression.”

A spokesman for GlaxoSmithKline, which makes Seroxat, said the authors had failed to acknowledge the “very positive” benefits of the treatment and their conclusions were “at odds with what has been seen in actual clinical practice.”

Hey, if you can remarket an antidepressant as another drug, as Lilly did by rebranding Prozac as a pre-menstrual issues drug after its patent expired, you’re going to be dollar-sensitive.

That said, as someone currently on citalopram (generic Celexa), and having run through comments on a post on this on Political Animal, I have a few thoughts.

First, if antidepressants did work BECAUSE they were placebos, why wouldn’t the placebo effect work with the first antidepressant? Why do so many people, unfortunately, try three or four before finding the right one for them?

Second, claiming a “spontaneous remission” for depression, saying that means we can and should go back to pre-drug days, is not just naïve but dangerous. Like a physical illness such as MS that goes into “remission” but then flares up again, depression can do the same.

Finally, we know too little, still, about brain chemistry to know exactly how antidepressants work. Therefore, claiming we know they don’t work is premature, even if that does prove to be the case 20-30 years from now.