By Dr. Ed Hendricks on March 9, 2009
New Obesity Drug?
Something which could cause a great deal of excitement is on the horizon in obesity treatment. Arena Pharmaceuticals, a San Diego biotech firm, has an anti-obesity drug in development. The drug, named Lorcaserin, activates specific brain serotonin receptors which suppress appetite, reduce food intake, and produce weight loss. This late-stage developmental drug is still several years away from possible FDA approval. Arena has it on the FDA approval track and has big event scheduled to occur in late March, 2009 when the company will first report results of a Phase 3 clinical trial. The company hasn’t revealed any details of the 2-year Phase 3 trial as yet, but if the results are as impressive as those of the Lorcaserin Phase 2 trials, and if Phase 3 trials raise no safety issues then Lorcaserin may be the drug everyone has waiting for.
The two-drug combination of phentermine and fenfluramine or, “Phen/Fen,” activated these same serotonin receptors. For many patients Phen/Fen was a magical combination, which made food cravings, especially carbohydrate cravings, disappear and produced almost effortless weight loss. Unfortunately, a small number of patients developed cardiac valve leakage caused by the fenfluramine because fenfluramine activates all serotonin receptors including the 5-HT 2B receptors on cardiac valves. The fenfluramines were withdrawn from the market. Although the FDA was suspicious for a while that phentermine could have played a part in causing the heart valve problem, it is well documented now that phentermine has no adverse cardiovascular effects. Phentermine was exonerated and remains the most frequently prescribed anti-obesity drug.
Lorcaserin should be cardiac-safe because it activates one and only one specific serotonin receptor, the 5-HT 2C receptor but does not activate the cardiac 5-HT 2B receptor. Patients in the Phase 3 trial were monitored with echocardiograms and Arena will be announcing the analysis of that data along with the efficacy data in late March. The results of the 12-week Phase 2 trial were recently published in the medical journal Obesity (Smith SR, Prosser WA, Donahue DJ, Morgan ME, Anderson CM, Shanahan WR. Lorcaserin (APD356), a Selective 5-HT2C Agonist, Reduces Body Weight in Obese Men and Women. Obesity 2008;17:494-503.). Adverse effects were limited to headaches, nausea, and dizziness. Headaches usually started on day one, lasted a few hours and were mild. Nausea was also typically a drug start up effect and then disappeared. Dizziness occurred in about 7% of the patients in the trial. There were no significant cardiac or psychiatric adverse effects.
Weight loss appeared at 2 weeks and was progressive throughout the 12-week trial. The weight loss achieved at 12 weeks was comparable to the weight loss at 12 weeks of other weight loss drugs such as sibutramine. The non-responder rate was very low with nearly all patients losing weight in the Phase 2 trial. This is interesting because in the Phase 2 trial the patients were not put on diets and did not receive even advice on changing behaviors. In other words, nearly all the patients lost weight by merely taking the drug and doing nothing else. If the Phase 3 trial results in about 3,000 patients confirms and extends the Phase 2 trial results in about 400 patients, Lorcaserin could be the next blockbuster obesity drug. This preliminary Phase 2 report show results for 12 weeks only but a crucial question is what happens in the next 12 weeks of therapy and thereafter. This is why the Phase 3 trial results are eagerly awaited.
Even if it is eventually approved by the FDA, the earliest date Lorcaserin might be available at pharmacies will likely be 2012. The FDA has been very slow to act on new drug applications lately and the agency has always been extremely slow in approving new obesity drugs. Overweight patients shouldn’t wait for a new drug before dealing with this illness.
It looks like Lorcaserin alone produces an average 3% weight loss at 12 weeks or about one third the weight loss our patients get on our Very Low Carbohydrate Diet program which includes a great deal of attention to behaviors and behavior modification without any weight loss drug. Our patients who have phentermine added, experience on average a 15% weight loss at 6 months. Although a 3% weight loss at the highest dosage at 12 weeks may seem low, one should remember this is in patients who aren’t even trying to lose weight – they just took the drug. I would expect Lorcaserin will be like any other drug in that it will do much better combined with a comprehensive weight loss program. Will Lorcaserin be a better drug than phentermine? We’ll see. It will most certainly be much more expensive than phentermine.
I’ll continue to watch for news on this exciting developmental drug and will post new information here in this Blog as it becomes available. Check back often.
Contact our non–surgical weight loss clinic, which serves Sacramento, Roseville, and surrounding areas, to schedule an appointment.
2310 Professional Dr., St. 200
Roseville, California 95661
Phone:916.773.1191
Fax: 916.773.0498
click for map & directions
2621 Capitol Ave.
Sacramento, California 95816
Phone: 916.551.1999
Fax: 916.551.1998
click for map & directions
Barbara Wendt said:
I was in the “Blossom” Study thru Radiant Research in Salt Lake City last year. I was wondering when Lorcaserin will be available and how will it be available (by prescription or what)
Dr. Ed Hendricks said:
Arena Pharmaceuticals plans to ask the FDA for marketing approval for Lorcaserin by the end of 2009. The FDA is typically slow to approve weight loss drugs, but a few Wall Street Analysts are predicting mid-2010 approval. If the FDA approves Lorcaserin, it will be available as a prescription drug perhaps a year from now or maybe sooner.
On September 19, 2009 Arena announced the results of the Lorcaserin BLOSSOM Phase 3 Trial. All FDA requirements for approvability were met in the trial so the company expects FDA approval will be granted. Approval will depend on the recommendation of the FDA’s Endocrinologic and Metabolic Drug Advisory Committee, made up largely of academic endocrinologists most of whom have no experience in treating obese or overweight patients. The committee has been notoriously fickle about recommending approval of weight loss drugs in the past – there’s no guarantee they’ll recommend approval.
Carla said:
I was a participant in the 2 year trial through Radiant Research in Stuart, Florida. I had great success with the trial. I lost 60 lbs. Since having finished the trial, I have slowly started gaining the weight back. I am afraid I will gain it all back and wanted to know if you knew of anyone that I could contact that may have some answers for me. I don’t want to return to the place I was at and am at a loss as to what to do at this point. Nothing has ever worked for me in the past.
Medifills said:
Very good information about losing weight and diet. I will put this to use.
Lorcaserin said:
News out on Dec 10, was encouraging for Arena. In clinical tests, it showed that Lorcaserin had a very low potential of being abused. They compared it to a placebo as well as a schedule 3 and 4 drug in a double blind. They even used a higher amount of Lorcaserin than what would typically be prescribed to show that people could take more than what was prescribed to them. No one really got a buzz so to speak. This may help to seal the deal to get it approved. Ultimately the FDA holds the cards and since certain trial drugs such as rimonabant where pulled from the EU etc, the FDA is indeed a little more strick in their review process. But news out also indicates that Arena’s next step it to submit it to the FDA for approval. Anyones thoughts on potentially prescribing this with Phentermine in the future?
Anthony said:
I very happy reading your post. Thank you so much for provide nice information.
Dr. Ed Hendricks said:
The combination of Lorcaserin and phentermine is a perfectly logical combination since one would expect it to mimic the effects of Phen/Fen combination with no risk of cardiac valve damage. Phen/Fen, a combination of phentermine with fenfluramine was a very effective combination widely used in the late 1990s until the fenfluramines were taken off-market after fenfluramine-induced cardiac valve disease was discovered. Lorcaserin was specifically engineered so as to have no cardiac valve effects. Even though phentermine/Lorcaserin hold great potential no one has tried it yet. If Lorcaserin actually gets FDA approval I expect someone will try the combination – time will tell.
Michael Ferro said:
I completely agree with everything in this post. keep up the good work
Hoodia Capsules said:
Thanks keep this blog updated,
Maxwell Bulgin said:
Hey mate, your blog’s design is great and i like it. Your posts are nice. Please continue this great work. Take Care…
chris Bickford md said:
I am waiting patiently for the FDA to approve the use of this most promising new med. If it
works anywhere near as well as fen/phen it will be VERY useful for those of us that are overweight, but unable to lose through normal means.
cbmd
Wihelmina Ruth said:
Just want to say your article is striking. The clarity in your post is simply striking and i can take for granted you are an expert on this subject. Well with your permission allow me to grab your rss feed to keep up to date with forthcoming post. Thanks a million and please keep up the ac complished work. Excuse my poor English. English is not my mother tongue.
how to make more money said:
This is the first time I’ve ever visited your website and I think the information here is simply awesome!
Natalie said:
Nice writing style.I came across your blog from Google and found it helpful. Have you been writing this blog for a while?Just the other day I recently started a blog on my own and its been a really fun process. I’ve met some great people since then but it is hard work sometimes! Oh well, much appreciated for your post!
FatLoss4Idiots said:
I really enjoyed this article, can I copy a paragraph to a new site that I’m building? I’ll add a link back to this page and credit you with being the author of course.
best hoodia said:
Its good to find some valuable information once in a while, keep it up.
Billy Portune said:
Valuable info. Even I accidentally found your site, I bookmarked it.
Jonah Nuffer said:
Very nice Blog! good to read!
Lorilee Halat said:
Superb articles regarding diet programs for weight loss fast . You made good quality tips there. I did a google search relating to the subject and discovered many people may come to an agreement with your site. Were did you get all the information from?diet lose weight
Ricky Shreves said:
Hi. I just want to say that it was a nice reading. I hope you come out with more interesting posts, because I bookmarked your website. All the best.
Belle Barella said:
I’m kinda interested in the subject too, so I hope you come out with more of the same stuff.
seolace said:
Nice post, thanks for writing!