This news release from Allergan reports results of a phase II clinical trial of botox (onabotulinumtoxinA) as a treatment for major depressive disorder. The study compared effectiveness of two different dosages of botox with placebo in women for up to 24 weeks of treatment. The release states that the 30-unit dose was superior to the placebo at three and nine weeks, but not at six weeks. The 50-unit dose was not superior to placebo.
The heading claims that the results support advancement of botox into larger phase lll trials, but further into the release we learn there was no statistically significant difference between treatment and placebo at the predetermined goal of six weeks. Additionally, the lower dose arm of the study outperformed the higher dose. As written, the heading and some introductory material are misleading.
With mental health concerns more and more in the spotlight of health policy in the United States, an effective treatment for depression would be important news. Current treatments for depression help about two-thirds of those with significant depression symptoms. A treatment with a different mechanism of action such as botox to help some treatment resistant patients would be a welcome addition to the therapeutic toolbox. However, this news release obscures the study results.
Botox has already been promoted for “off label” use to treat depression for some time. HealthNewsReview.org has previously explored the marketing of botox for depression and other conditions.
No mention is made of the cost of botox. GoodRx lists one 100-unit vial of botox selling for around $615 on average in the United States.
We really don’t have a good idea from the release of the degree of benefit. Some numbers provided trend towards statistical significance, but there is a big difference between statistical significance and clinical significance. How much of a change in these rating scales makes a difference to the way a patient is really feeling such that it makes a difference in their lives? Also the fact that one dose of the drug seemed to provide effects and the other higher dose didn’t calls into question the whole idea of why botox may work for depression. The theory is that by paralyzing certain muscles in the face, botox affects emotions often reflected in those muscles. So shouldn’t some benefit be present or comparable at the higher doses?
No mention is made of possible negative side effects. According to MayoClinic.com, possible side effects include “pain, swelling or bruising at the injection site, headache or flu-like symptoms, droopy eyelid or cockeyed eyebrows, crooked smile or drooling, eye dryness or excessive tearing.” In rare cases, the effect of botulinum toxin can spread to other parts of the body and cause botulism-like signs and symptoms.
Information is provided about the study design (a randomized, double-blind, placebo-controlled, single treatment study), the number of study volunteers (258 adult women), the proportion of people in each arm of the study, and the length of the trial.
But the release seems to go to pretty significant lengths to conceal the fact that the primary outcome was negative. It introduces the results with the sentence: “The BOTOX® 30 U dose demonstrated numerically superior efficacy in MADRS total score compared to placebo.” However, the release itself indicates that is not true. At the predetermined endpoint of six weeks, there was no statistically significant difference between either dose of botox and the placebo groups.
We also have concerns about the headline which announces that the results support advancement of botox for treatment of major depressive disorder. That’s a stretch. Other outside experts have called these results mixed at best, unimpressive at worst.
The release does not engage in disease mongering, but nor does it provide us with any context about major depressive disorder or describe how botox works to reduce depression symptoms.
It is clearly stated that the study was funded by Allergan, the same company that produces botox.
The article makes no comparison between botox and current treatments for depression so we’re left wondering: what does botox bring to the table? How does its benefits compare with medication? Does botox have fewer side effects? Does it cost less than other therapies? Readers are given no context within which to interpret the news.
No statement is made about the availability of botox, but readers can reasonably assume that it will continue to be widely available.
Allergan is not the first to test the effectiveness of single doses of botox to treat depression. Other researchers have conducted small, placebo-controlled studies with encouraging results, and a mention of the previous research should have been included in the release.
The release doesn’t rely on sensational language.