FDA Approves VBLOC Treatment For Obesity

We don’t have great treatments for obesity, so every new evidence-based tool in the obesity treatment tool box is something to look at closely. The latest addition, just approved by the US FDA for the treatment of obesity  in adults with a BMI of 40 to 45 kg/m2 or a BMI of 35 to 39.9 kg/m2 with a related health condition, is something I’ve posted about before – VBLOC or the vagal “pacemaker” as it is sometimes referred to. Indeed, Enteromedics‘ rechargeable Maestro system is very much like an implantable cardiac pacemaker, in that it delivers an electronic signal – in this case to block the action of the vagus nerve. The exact mode of action is not entirely clear but the weight-loss mediating effect (in the 10-15% average range) is largely a result of reduced appetite and increased satiety. Here is how Enteromedics describes its system: “The Maestro® System consists of a subcutaneously implanted rechargeable neuroregulator and two electrodes that are laparoscopically implanted by a bariatric surgeon. It delivers VBLOC® vagal blocking therapy via these electrodes that are placed in contact with the trunks of the vagus nerves just above the junction between the esophagus and the stomach. The device intermittently blocks vagal nerve signals throughout the patient’s waking hours. The Maestro System is recharged using an external mobile charger and transmit coil worn by the patient. The device can be non-invasively programmed, and it can be adjusted, deactivated, reactivated or completely removed if desired.” Obviously this is far from the be-all and end-all of obesity treatments – especially as it does not seem to work for everyone. Thus, the recently published results from the pivotal study (discussed here),  was certainly far less impressive than the company may have hoped for. Just where VBLOC treatment will ultimately find its place in bariatric care remains to be seen – this is certainly a space to watch. @Dr. Sharma Edmonton, AB  

VBLOC Device Shows Promise for Diabetes Treatment

Regular readers will recall previous posts on the VBLOC device, which uses intermittent electrical signals to block the vagal nerve thereby leading to weight loss. The previous post followed Enteromedic’s announcement that the early results from the EMPOWER study failed to quite meet its primary and secondary efficacy endpoints (resulting in a 70% fall in share price). Yesterday, however, the share price of Enteromedics more than doubled after the company announced the follow-up results of two studies, to be presented in the coming days at the American Society for Metabolic and Bariatric Surgery Meeting in Las Vegas. After soldiering on in the randomized, double-blind, controlled pivotal EMPOWER Study, participants now at 20 months experienced an almost 20% excess weight loss, while averaging 9 hours of device use per day. Perhaps more interestingly, in another ongoing study (VBLOC-DM2 ENABLE), obese patients with Type-2 diabetes mellitus showed an improvement in HbA1c levels of 0.8% as well as a 25% excess weight loss over 12 months while averaging about 14 hours per day of therapy with the implantable Maestro RC System. The novelty of this second generation Maestro device lies in the rechargeability of the implanted batteries via an external mobile charger and transmitter coil that can be worn for a few hours each week, thereby allowing delivery of a far more extensive treatment that with the previous version of the device. Although this treatment required laparoscopic implantation of electrodes and the battery pack, with the usual risks entailed in such surgery, the treatment appears to be well tolerated with few side effects. As outlined in yesterday’s press release, the company certainly appears optimistic about the future of this treatment for obesity and diabetes – the investors clearly appear to share this enthusiasm. AMS Edmonton, Alberta p.s. You can now also follow me and post your comments on Facebook

Obesity Weekend Roundup, January 17, 2015

As not everyone may have a chance during the week to read every post, here’s a roundup of last week’s posts: Canadian Obesity Summit: Late-Breaking Abstract Submission Now Open Leptin Mediates Obesity Hypertension – End Of Story! Guest Post: Bariatric Foodie FDA Approves VBLOC Treatment For Obesity The Physiological Benefits Of Laughter Have a great Sunday! (or what is left of it) @DrSharma Reykjavik, Iceland

Efficacy of Vagal Blockade For Obesity Treatment Remains Vague

Regular readers may recall past posts on the use of intermittent electrical blockade of the vagus nerves (VBLOC) as a means of reducing food intake to promote weight loss. Now a large randomised controlled study of vagal blocakade, published by Sayeed Ikramuddin and colleagues, published in JAMA, reports on rather disappointing outcomes with this treatment. In this study (ReCharge), conducted  at one of 10 sites in the United States and Australia between May and December 2011, 239 participants with a BMI greater than 40 (or greater than 35 with at least one comorbidity), were randomised to receiving an active vagal nerve block device (EnteroMedics’ Maestro® Rechargeable (RC) System, n=162) or a sham device (n=77). Over the 12-month blinded portion of the 5-year study (completed in January 2013), the vagal nerve block group lost about 9% or their initial body weight compared to only 6% in the sham group. In addition to this rather modest difference in weight loss between the groups (about 3%), participants in the active treatment group also experienced a number of clinically relevant adverse effects (heartburn or dyspepsia and abdominal pain). Thus, overall these rather disappointing results are in line with the previously disappointing observations in the smaller MAESTRO trial. Based on these findings, it seems that intermittent electrical blockade of the vagal nerve may not hold its promise of a safe and effective long-term treatment for severe obesity after all. @DrSharma Edmonton, AB Ikramuddin S, Blackstone RP, Brancatisano A, Toouli J, Shah SN, Wolfe BM, Fujioka K, Maher JW, Swain J, Que FG, Morton JM, Leslie DB, Brancatisano R, Kow L, O’Rourke RW, Deveney C, Takata M, Miller CJ, Knudson MB, Tweden KS, Shikora SA, Sarr MG, & Billington CJ (2014). Effect of reversible intermittent intra-abdominal vagal nerve blockade on morbid obesity: the ReCharge randomized clinical trial. JAMA, 312 (9), 915-22 PMID: 25182100

Maestro Vagal Stimulation Device Fails to Measure Up?

As blogged previously, Enteromedics recently got European approval for their Maestro device for the treatment of obesity. The system is designed to reduce food intake by blocking vagal signals from the stomach and gut to the brain. The system is implanted laparoscopically and uses high-frequency, low-energy electrical impulses to intermittently block vagal activity (therefore this has also been referred to as VBLOC therapy). On Friday, Enteromedics now reported rather disappointing preliminary results from their pivotal randomized, double-blind, placebo-controlled EMPOWER study, which failed to meet its primary and secondary efficacy endpoints. In response to this announcement shares of Enteromedics fell by 70%. This is obviously bad news for the company, but, given past failures with other approaches to neuro- or gastro-stimulation treatments, perhaps also for other companies heavily investing in electrical therapy for weight management.  While the pre-clinical data and preliminary results in select patients, often look promising, confirming these findings in subsequent larger long-term studies apparently proves challenging.   Nevertheless, it may well be that for select patients, neurostimulation could be an effective and safe option – the million-dollar (no pun intended) question however remains: who exactly are these patients? Once again, it is clear that in obesity treatments, one size will not fit all. AMS Edmonton, Alberta