While America waits for Arena and Eisai to finally get the green light from the FDA and the DEA to begin marketing the weight-loss drug Belviq (lorcaserin), Arena shareholders and European patients are waiting with bated breath for a nod from the CHMP, which will pave the way for the European Medicines Agency to approve marketing authorization for Belviq.
The various investor boards are buzzing about how vital a European approval for Belviq would be for Arena. And you cannot argue that point, since it is important for every company to increase its market potential by extending the geographical reach of its products. But here's why I think it's not going to matter too much to Arena's bottom line even if Belviq does not gain European marketing authorization: very few patients will be able to receive the drug. Am I talking about low prescriptions, poor reimbursement or reluctance of patients to pay out of pocket? Yes, I am talking about all of these issues, which together will mean very few patients will receive Belviq.
The demand for obesity drugs is certainly high in Europe. Decision Resources epidemiologists estimate the obesity prevalence in the United Kingdom, which has the dubious honor of being the fattest nation in Europe, to be as high as 26% among the adult population. More worrying is the 38% of the UK population that is clinically overweight, as a sizeable proportion of the overweight population will slide into the obese category in the coming years. Germany is not far behind, followed by Spain and France. All of us in Europe are following America's lead as one of the fattest nations on earth?where 37% of the adults are clinically obese and another 33% are overweight. (And yes, you read this correctly. Since 2009, the U.S. has had more obese than overweight adults?a sobering fact considering the long-term cost burden of obesity.)
And so it is no wonder that Belviq is generating a lot of buzz. In fact, because so few drugs have been approved for obesity over the past few decades, each green light from the regulatory agencies is a cause for celebration. We were treated to two FDA approvals in 2012?for Belviq and Vivus's Qsymia (phentermine + topiramate). And while it no longer looks like Qsymia has any chance of approval in Europe following Vivus's unsuccessful appeal, there is still hope for Belviq. Investors are salivating at the potential for Belviq in Europe, especially since there is no significant competition (Roche's Xenical is the only prescription weight-loss drug currently available in Europe, following the withdrawal of Abbott's Meridia, Servier's Mediator, and Sanofi's Acomplia over the past few years).
So here's my take on why very few patients will receive Belviq (and why sales figures will be low in Europe).
- Belviq might be safe enough to merit approval, but it falls short in terms of weight-loss efficacy. Newly published data from a primary market research survey authored by Decision Resources show that an obesity drug needs to elicit a minimum 6-10% mean weight-loss efficacy before physicians will consider prescribing it. However, the sweet spot is 11-15% average weight loss, at which point a sizeable proportion of prescribers will put patients on a drug. At just 4-5% placebo-adjusted weight loss, Belviq falls short of these thresholds. In fact, even Qsymia falls slightly short of the second level of expectation, at roughly 9-10% placebo-adjusted weight loss. Although these data are for U.S. prescribers, we can infer that European prescribers probably share similar expectations.
- The true potential for Belviq is as an add-on therapy for phentermine. However, in our survey (see graphic below), a sizeable proportion of U.S. endocrinologists are reluctant to prescribe such a combination, even if it is approved by the FDA (due in part to memories of the Fen-Phen debacle from the mid-1990s). The proportion of physicians who would prescribe Belviq together with phentermine increases by 50% if the FDA approved the two drugs for combination use, however this would make no impact on European sales, since phentermine is not marketed in Europe (and there is no indication that it will become widely available there any time soon).
- Our survey data show that we can expect poor reimbursement coverage by commercial and Medicare plans in the U.S. based on the proposed $200/month ($6.67/day) price point for Belviq, with many health plans intending to exclude coverage for Belviq altogether. This means that many U.S. patients will have to pay fully out-of-pocket for the drug. In the major European markets, we similarly expect that there will continue to be no reimbursement for obesity drugs, so most patients will have to pay out of pocket for Belviq. And whether you are counting in pounds or euros, I don?t think many folks are going to pay the equivalent of $6.67/day for the chance of losing an average of 4% of their body weight.