an obesity drug to show an extra 5 percentage points of weight loss on average. The difference is in the same ballpark, however, as what Arena showed in the so-called Bloom study earlier this year, in which lorcaserin was about 3.6 percentage points better than placebo.
So why does Lief say he’s excited? Vivus produced what it called “unprecedented” effectiveness, (and wowed investors last week) when it reported its drug had a 9.4 percentage point advantage over a placebo in a separate clinical trial.
It turns out that obesity drug developers have more than one way to impress the FDA, and Arena passes that test. The Blossom study being reported today shows that 47 percent of patients on the twice-daily Arena drug lost at least 5 percent of their body weight, while just 25 percent did that well in the placebo group—and the FDA has said it considers such a drug “effective” if it can help about twice as many people lose that much weight as a placebo.
Particularly since the FDA will require a squeaky-clean safety profile for an obesity drug that might be taken by millions of people without an imminent life-threatening disease, safety is critical. Based on the Blossom results, Arena has good reason to breathe a sigh of relief.
That’s because the company’s drug is designed to work in a similar way as Wyeth’s fen-phen combination drug did in the 1990s, before that drug was pulled off the market over damaged heart valves. The Arena drug is supposed to be more specific—to interact with an enzyme in the brain that controls feelings of fullness—without hitting a similar enzyme on the heart that led to the undoing of fen-phen.
What Arena has learned, by looking at sophisticated echocardiogram images of the heart in more than 7,000 patients, is that its drug doesn’t appear to damage heart valves like fen-phen. The most common adverse events reported in the trial were upper respiratory tract infections, stuffy nose, and headache, although only a few more patients reported those effects on the drug versus the placebo.
As I described in a preview about these clinical trial results, Arena is trying to play up its drug’s clean safety profile as an advantage. It’s still early days in this face-off, but it appears that the rivals are starting to find their niches, with one likely to help people lose the most weight (Vivus), another that helps to help treat the related ailments that stem from obesity (Orexigen), and one that positions itself as the safe alternative for the masses (Arena).
Lief made it clear to me that Arena has its cross-hairs set on the thousands of primary care physicians in the U.S. who are on the front lines of the nation’s obesity epidemic. Arena will need help from a partner with serious marketing muscle to reach this vast audience of doctors and patients, but Lief sounds like he has TV commercials dancing through his head already. What it basically boils down to is a pitch that goes like this: Arena’s drug won’t hurt, and might help.
“We think we can change the way primary care physicians treat weight loss,” Lief says.
He adds: “It’s not just about efficacy, it’s about safety as well. Because our drug is so safe, we think we’ll address the broadest patient population for weight loss.”
Arena will host a webcast at 8 am Eastern/5 am Pacific time today to discuss the results in greater detail with investors.