In drug development, a hint of efficacy is usually a lot worse than no efficacy at all. At least when a drug fails hard, it's easy to throw it on the shelf and focus on something else. When there's a hint of efficacy, drugmakers have to make the hard choice of exploring the hint, sinking more time and money into a drug that might not work, or end the development despite the small hope of potential.

Let's hope Eli Lilly (NYS: LLY) doesn't make the wrong one.

On Friday, the pharma said its Alzheimer's disease drug, solanezumab, failed two phase 3 trials. Both trials measured cognitive and functional decline of the patients, and the drug failed to show an effect compared with placebo for both measurements in both clinical trials. It really doesn't get much worse than that.


Except, but, bar, save for, however -- insert your own glimmer of hope -- if you combine the two trials, solanezumab slowed the cognitive decline compared to placebo. If you just look at the patients with mild Alzheimer's disease, the pooled data shows statistical significance, but the pooled data for moderate Alzheimer's disease patients doesn't.

Lilly hasn't released the full data set yet, but I'm willing to bet if you stand on your head and read the data upside down, you can probably find something else interesting that solanezumab does. Cure arachnophobia in left-handed women with blonde hair, perhaps?

It's not quite that bad, because looking at efficacy in the pooled data was a pre-specified analysis, but it isn't going to get the drug approved, given that it failed the primary analysis of the individual trials. At the very best, Eli Lilly will have to run two more clinical trials, each one as large as the first two combined, in hopes of showing efficacy, and even then, the FDA would probably want to see improvement in patient function as well as a cognitive improvement.

If it takes 2,000 patients per trial to prove that a drug works, it's likely that it isn't doing all that much to help the patients. With large numbers, small decreases in cognitive or functional decline can be statistically significant, but that doesn't make them clinically meaningful.

Earlier this month, Pfizer (NYS: PFE) , Johnson & Johnson (NYS: JNJ) and Elan (NYS: ELN) ditched their similar-acting Alzheimer's disease drug, bapineuzumab, after it failed a couple of clinical trials. Despite the hint of efficacy, Eli Lilly would be wise to do the same.

What stocks are the smart investors buying? Find out which sector Warren Buffett and others are interested in by grabbing the Fool's report "The Stocks Only the Smartest Investors Are Buying." Get it for free.

The article Forget the Hint of Efficacy originally appeared on Fool.com.

Fool contributor Brian Orelli holds no position in any company mentioned. Check out his holdings and a short bio. Motley Fool newsletter services have recommended buying shares of Johnson & Johnson and creating a diagonal call position in Johnson & Johnson. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days. The Motley Fool has a disclosure policy.

Copyright © 1995 - 2012 The Motley Fool, LLC. All rights reserved. The Motley Fool has a disclosure policy.


Increase your money and finance knowledge from home

Socially Responsible Investing

Invest in companies with a conscience.

View Course »

Basics Of The Stock Market

Stock Market 101 - everything you need to know but were afraid to ask!

View Course »

Add a Comment

*0 / 3000 Character Maximum