The skinny on treating obesity – devices vs drugs

This week ReShape Medical’s gastric balloon became the fourth device to gain FDA approval as a treatment for obesity, and as the first device not to require any form of surgery it has been granted a label allowing it to treat less ill patients.

In terms of accessible patients, though, obesity devices are still behind drugs, as the table below shows. And the same is true when it comes to efficacy; according to published pivotal trial data, drugs – particularly Vivus’s Qsymia – permit greater weight loss than the two most recent device approvals. So what kind of niche can these products hope to occupy?

The ReShape Dual balloon is inserted into the stomach via the mouth where it is inflated with a sterile solution; by taking up room in the stomach, it makes the patient feel full. The device is only temporary and is removed six months later.

It is in fact two balloons, as the name suggests. That way, if one balloon ruptures, the other will anchor it in the stomach so it will not reach the bowel and possibly cause a blockage or perforation.

The FDA has approved it for adult patients with a body mass index (BMI) of 30 to 40kg/m2 who have at least one obesity-related condition. Around 35% of people in the US have a BMI of over 30 – and are therefore obese – and 6.5% have a BMI of over 40, so this ten-point range captures a decent chunk of the country’s population.

But other devices can be used in more patients. The two FDA-approved gastric bands address the same population as ReShape Dual, but may also be used in the additional 6.4% who are morbidly obese. In practice there are limits to the number of patients who can withstand the implantation procedure – even though these bands are placed via keyhole surgery the operation can still pose risks.

The last device has a more restricted label. The Maestro device is implanted under the skin and sends electrical impulses to the vagus nerve, which innervates the stomach, making patients feel full. Approved in January, it may be used only in morbidly obese patients or those with severe disease – BMI of 35-40 – if they have a related condition (US approval for Enteromedics’ expensive weight loss shocker, January 15, 2015).

To be given any of these devices a patient must have failed non-surgical weight-loss approaches, such as supervised diet, exercise and behaviour modification programmes.

Of the devices for obesity, the gastric bands can address the widest patient population. They also seem to be the most effective of the devices, though they do not appear to have been tested in placebo-controlled trials. This means that comparisons with other technologies are tricky – and comparing the results across several different trials is always imperfect and should be taken as an indication only.

LAP-Band, the product sold by Allergan to Apollo Endosurgery in 2010 as it sales were lacklustre, permitted 65% excess weight loss, compared with 24% for the Maestro system Gastric bypass surgery, however, is more effective still, allowing patients to lose 70% of their excess and 28% of their total weight.

Big money

Placebo-adjusted data is available for the two devices approved this year, with Maestro and ReShape permitting loss of 3.2% and 2.5% of total bodyweight on average. This is similar to that achieved with Eisai’s Belviq, approved in the US three years ago. But since then, more effective pharmacological options have arrived, notably Vivus’s Qsymia, which achieved up to 9.4% in clinical trials.

The drugs also leave devices standing when it comes to labelling, with the four main options approved for use in patients with BMI as low as 27.

And then there is the cost. Open gastric bypass surgery costs around $25,000 and the laparoscopic procedures to implant gastric bands around $15,000. EnteroMedics’ Maestro nerve-blocker is thought to cost around $20,000. According to analysts from Canaccord, in Europe implantation of the ReShape balloon costs an average of €5,500 (around $6,000).

A year’s treatment with arguably the most effective drug, Qsymia, costs $2,351 per patient according to EvaluatePharma’s Sales, Volume and Pricing module. The decision as to which approach is the most cost-effective is therefore a balance: if the patient seems likely to live for another 10 years or more, banding or even surgery might work out cheaper than drugs – if the patient is capable of undergoing the intervention. There is another advantage with devices in that compliance with the therapy is ensured.

Niches

Maestro has its own niche, albeit perhaps not an enormous one, being of use in severely ill patients for whom surgery poses too great a risk and who cannot wait for the drugs to take effect. The rationale for ReShape is less clear. It offers weight loss of around the same degree as Belviq or Contrave but rather less than Saxenda or Qsymia, and as a temporary implant it does not seem clear how long the benefit could be expected to last.

According to the FDA patients should stick to a diet and exercise plan during the period of the balloon’s implantation and thereafter, “to maintain their weight loss following its removal”. Presumably the hope is that after six months of balloon therapy the patients have learned better eating habits, but with around 65% of general dieters returning to their pre-dieting weight within three years, this may be optimistic.

It is not a bad idea to have a wide range of possible treatments for an illness. But for a product to succeed commercially it must offer some sort of advantage over the other options, and it is difficult to see what ReShape’s might be.

To contact the writer of this story email Elizabeth Cairns in London at [email protected] or follow @LizEPVantage on Twitter