Contrave Rejection and Obesity Drugs’ Future

Today’s a somber day for anyone looking to develop a weight-loss medication. Orexigen’s potential obesity drug Contrave has failed to win FDA approval, just as Arena’s Lorqess and Vivus’s Qnexa before it. In other words, none of the big contenders in the diet drug race we’ve been covering for nearly a year has panned out. Contrave came into FDA decision-day with a a glimmer of hope behind it. Last December, an FDA panel voted in favor of approving Contrave, though they recommended that Orexigen conduct a clinical trial after approval to track the drug’s cardiovascular risk. In contrast, Lorqess and Qnexa hadn’t gotten a thumbs-up from the panel. But the agency turned out to be more conservative than its advisory panel. In a so-called Complete Response Letter, FDA told Orexigen it needed to conduct that cardiovascular clinical trial BEFORE Contrave could be approved, not after approval. Orexigen’s stock fell over 70% on the news this morning. “Such a study would be huge, expensive, and would take years, and the request probably means that Contrave will never hit the market,” writes Forbes’s Matthew Herper. So where do we go from here? I hesitate to say that the obesity drug field is dead. We’ll certainly continue to see scholarly papers about promising new obesity drug targets. But on the clinical side, the focus is going to have to shift away from weight loss to treating the conditions that tend to go hand-in-hand with obesity, like diabetes. That’s what could help tip the safety-efficacy balance in a way that leads to new drug candidates being approved by FDA. This is not a new idea- for instance, C&EN contributing editor Aaron Rowe has covered companies’ efforts to mimic bariatric surgery‘s beneficial effects on diabetes with a pill. Pfizer is in Rowe’s story with a potential diabetes drug in clinical trials. The molecule targets an enzyme that reassembles triglycerides. One of its entries at clinicaltrials.gov says it all: “It is anticipated that PF 04620110 will have anti diabetic effects through inhibition of intestinal triglyceride absorption and potentially weight loss.” Pfizer exited obesity drug research in 2008. But it didn’t abandon efforts to treat some of the conditions that make obesity unhealthy. If targeting a certain enzyme happens to help with both diabetes symptoms and weight loss, so much the better. But weight loss isn’t the top...

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Arena’s Weight-Loss Pill Lorqess (lorcaserin): Waiting For FDA
Oct21

Arena’s Weight-Loss Pill Lorqess (lorcaserin): Waiting For FDA

Tomorrow is the deadline for the Food and Drug Administration to make a decision about whether or not to approve Arena Pharmaceuticals’ experimental obesity drug Lorqess (lorcaserin). In advance of the decision I’ve recapped some Lorqess news and information from the last several months. We will update you when FDA’s decision comes in. Of the three potential new diet pills racing to reach the market, Lorqess (lorcaserin) is the only one where the active ingredient is a completely new molecule. Its competition, Vivus’s Qnexa and Orexigen’s Contrave, are both combinations of drug molecules that have already been FDA-approved for other conditions. Lorqess targets an appetite-suppressing serotonin receptor located in the brain. It’s the same receptor that was targeted by fenfluramine, an ingredient in the infamous Fen-Phen obesity drug combo. Fenfluramine was associated with heart valve damage and a fatal lung disorder- it was pulled from the market in 1997. Lorcaserin is different from fenfluramine- it is more selective for the specific subtype of serotonin receptor found in the brain and avoids the one that’s found in the heart. Arena’s idea behind Lorqess was that a more selective drug might have the weight-loss benefits with fewer side effects. Arena has had to pay special attention to safety throughout lorcaserin’s development and they haven’t run into heart valve trouble. In July, Arena landed a partner for marketing Lorqess- Japan’s Eisai. But last month, when an FDA panel met to discuss Lorqess, the outcome was disappointing for Eisai and Arena. Background materials for the panel session raised questions about malignant tumors that occurred in rats given high doses of lorcaserin. And the panel itself recommended that FDA not approve Lorqess by a 9 to 5 vote. The panel decided not enough data was available to assuage concerns about safety, and was also concerned about how the drug would work in a wider population than was tested during clinical trials. In the aftermath of the panel recommendation, analysts suggested a number of pieces of data that Arena could provide to improve its overall package of information about Lorqess, and thus the drug’s chances. But many of the suggestions, which included a detailed study of the mechanism behind the rat tumors, and a Phase II proof of concept trial of lorcaserin and phentermine in diabetics, take years, not months. Today’s FDA decision is sure to set the tone for the next couple of months, since Lorqess is the first of the three big contenders to be judged. FDA could decide to ask for more data on Lorqess, or make a decision outright. Stay...

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Abbott Takes Diet Drug Meridia (Sibutramine) Off The Market

A diet pill bit the dust today- the Food and Drug Administration has asked Abbott Laboratories to take its drug Meridia off the market in the U.S. Meridia, or sibutramine, was approved by FDA in 1997, but the company voluntarily pulled Meridia after FDA’s request, and is also halting sales of the drug in Canada and Australia. FDA’s request was based mostly on a large study from last fall called the SCOUT trial. The trial suggested that patients on Meridia had more cardiovascular events, such as heart attacks and strokes, compared to patients taking a placebo. “Meridia’s continued availability is not justified when you compare the very modest weight loss that people achieve on this drug to their risk of heart attack or stroke,” said John Jenkins, M.D., director of the Office of New Drugs in the FDA’s Center for Drug Evaluation and Research (CDER), in an FDA press release. “Physicians are advised to stop prescribing Meridia to their patients and patients should stop taking this medication. Patients should talk to their health care provider about alternative weight loss and weight loss maintenance programs,” Jenkins said. Meridia was already pulled from the market in the UK and other European nations earlier this year. You can click here to read more about how the drug works. And last month an FDA advisory panel was split as to whether to keep Meridia on the market here in the U.S. Of 16 panelists, 8 voted to withdraw the drug, 2 voted to keep it on the market with more strict warning label language, and 6 voted to keep it on the market with label revisions and restrictions on which doctors can prescribe the drug. The loss of Meridia isn’t a big blow to Abbott’s stock. Prescriptions for Meridia have already dropped over the years because of safety concerns, from a high of 1.3 million prescriptions in 1998 to 250,000 in 2009, according to FDA. But the next wave of obesity drug news, should it be similarly negative, could take a bigger toll on the companies involved, which are both smaller than Abbott. Mark your calendars for October 22 and October 28- these are the goal dates for FDA to finish reviewing applications for Arena Pharmaceuticals’ drug candidate Lorqess and Vivus’ Qnexa. FDA panels have recommended against approving both drugs. UPDATED 3:59 PM- to reflect withdrawal of Meridia from Canada and Australia as well as...

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FDA Panel Thumbs-Down For Arena and Eisai’s Diet Pill Lorcaserin (Lorqess)
Sep17

FDA Panel Thumbs-Down For Arena and Eisai’s Diet Pill Lorcaserin (Lorqess)

Yesterday brought yet another disappointment to the obesity drug development field- an FDA panel recommended rejecting Arena and Eisai’s potential diet pill lorcaserin (Lorqess) by a vote of 9 to 5. The message from the panelists was that not enough data was available to assuage concerns about safety, as well as concerns about how the drug would work in a wider population. This marks the second thumbs-down for a prospective obesity drug this year. Vivus’s drug candidate Qnexa received a ‘no’ vote from the panel in July. Going into the yesterday’s panel, the mood wasn’t exactly sunny. As I wrote yesterday, the FDA briefing documents for lorcaserin contained an unexpected safety surprise. The agency was concerned about malignancies that cropped up in rats taking high doses of lorcaserin. And Arena’s stock had tanked on the news. At the panel, Arena tried to allay FDA’s concerns right off the bat- in its presentation to the panel, the company said that the tumors were attributable to rat-specific mechanisms, so they wouldn’t apply to people. The company even presented a slide listing FDA approved drugs that showed higher rates of rat cancers than lorcaserin (I do not have this information but will update if I get it). The company reiterated that in clinical trials, patients taking lorcaserin did not have an increased risk of cancer. FDA’s briefing documents also contained a safety note about heart valve problems. As I’ve written before, lorcaserin had a lot to prove in this department. It targets the same serotonin receptor as fenfluramine, an ingredient in the infamous Fen-Phen obesity drug combo. Fenfluramine was associated with heart valve damage and a fatal lung disorder- it was pulled from the market in 1997. But lorcaserin is different from fenfluramine- it is more selective for one specific subtype of serotonin receptor and avoids the one that’s found in the heart. Arena had surmised that this would help avoid the valve problems that plagued fenfluramine, and the company has had to pay special attention to heart valve safety throughout lorcaserin’s development. The reason FDA is concerned is that their statistical analysis of Arena’s heart valve data (using a different method from Arena) suggests a risk for heart valve damage for patients on lorcaserin. FDA said the company could not statistically rule out a 50% increase in the risk of heart valve problems. At the panel, Arena defended its own data and statistics and said it was committed to continued safety monitoring in a post-approval period. But at the end of the day, it was the safety-efficacy balance that led to the thumbs-down vote from FDA’s panel. As I wrote back...

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Waiting For Arena, Thoughts On Meridia

Today the second of three potential drugs in the weight-loss race is in the hot seat- Arena Pharmaceuticals’ lorcaserin, which we recently learned will be called Lorqess, if approved. An FDA panel is meeting to decide whether it will recommend the drug for approval. I’m following two liveblogs of the panel, from Lisa LaMotta of Minyanville and Adam Feuerstein of TheStreet.com, and will post my thoughts on the aftermath tomorrow. Obesity drug watchers are looking for clues about today’s panel based on one that happened yesterday- that was when Abbott Laboratories’ obesity drug Meridia, on the market since 1997, came under FDA’s microscope. Meridia works by blocking reuptake of the neurotransmitters serotonin and noradrenalin in the brain, leading to a decrease in appetite. It’s effective at helping patients shed pounds, but the drug also boosts blood pressure and heart rate. So doctors and patients have had to deal with a tradeoff between weight loss efficacy and safety (this theme seems to come up a lot in the obesity drug field). Things shifted last November, when a large study called the SCOUT trial suggested that patients on sibutramine had more cardiovascular events compared to patients on placebo. As this WebMD article puts it: The drug is already not supposed to be used in patients with known cardiovascular disease. But experts said they were troubled that many patients with undiagnosed disease could be at greater risk if they use the drug to lose weight. In the aftermath, sibutramine was pulled from the market in the UK and other European nations. And stateside, concern mounted. Which brings us to yesterday’s panel. The panel vote was split as to whether to keep sibutramine on the market. Of 16 panelists, 8 voted to withdraw the drug, 2 voted to keep it on the market with more strict warning label language, and 6 voted to keep it on the market with label revisions and restrictions on which doctors can prescribe the drug. (Hat tip to Shelley Wood at theheart.org for getting the vote results up on Twitter asap). So in short, it’s not clear to me what will become of Meridia. As for whether the Meridia panel outcome will affect the Lorqess panel today, Leerink Swann analyst Joshua Schimmer wrote in a note to investors that FDA’s safety concerns for lorcaserin/Lorqess are likely to be different than the concerns about sibutramine/Meridia. “Because lorcaserin drops both heart rate and blood pressure (albeit in a non-statistically significant manner), we believe the CV issue will not be a major issue,” he wrote. But FDA’s briefing documents for Lorqess had a safety surprise, which Schimmer says may come into play....

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