I have to start with a disclaimer: this blog is not actually about Botox. It is about study involving a different form of botulinum toxin called Xeomin and its use for essential tremor (ET). You are already familiar with the name Botox for its ability to “miraculously” erase wrinkles, and you may know about its other clinical uses. You may not yet know about Xeomin—but that is the actual topic at hand.
Botox and Xeomin are two brands of an injectable preparation of botulinum toxin (BTX), a potentially deadly agent produced by a certain bacteria. When medically prepared and injected, BTX blocks nerve transmissions to muscles, causing the muscles to relax. This is what “erases” the appearance of wrinkles, and also eases tremors or other conditions like dystonia (severe uncontrollable muscle contractions).
Xeomin (incobotulinumtoxinA) differs from Botox (onabotulinumtoxinA) in the following waysi:
- Xeomin’s effects start in 1-3 days and acts gradually, whereas Botox starts working in 2-3 days
- Xeomin is considered a “purer” form of botulinum toxin since it is prepared by removing the complexing proteins that are bonded in the Botox preparation. This means there is less risk of developing resistance to Xeomin. NOTE: if a person is already resistant to Botox, they will probably be resistant to Xeomin.)
- Xeomin’s effects are slightly longer-lasting than those of Botox in clinical studies.
Study shows more effective way to administer Xeomin for ET
A multi-center clinical study evaluated the safety and effectiveness of customized injections of incobotulinumtoxinA (Inco A or Xeomin) for hand tremors due to ET and Parkinson’s disease.ii While it is recognized that BTX can control tremors, a standard pattern of injections for every patient has a high rate of hand weakness as a side effect. Thus, the study team was exploring tailoring the injection sites to each patient in an attempt to reduce this complication.
This study was a double-blind, placebo-controlled, crossover trial—a design that is a high level of research. It was relatively small (33 patients) and was conducted from July 2013 to July 2016. Each patient was evaluated to identify the muscles involved in their tremor, varying from 8-14 muscles in the hand and forearm. They were then injected with IncoA into the particular muscles in their case.
According to a Neurology Adviser news report about the study,
…participants in the incobotulinumtoxinA vs placebo group showed significant improvement at both 4 and 8 weeks, but no further improvement considered statistically significant was detected at weeks 12 and 16, indicating that the average response to incobotulinumtoxinA lasts between 8 to 12 weeks. More than half (53%) of participants in the incobotulinumtoxinA group and 15% in the placebo group reported an improvement in their condition using the Patient Global Impression of Change scores. Mild hand weakness was only reported by 6 patients in the incobotulinumtoxinA group and 4 patients in the placebo group.iii
This study demonstrates 2-3 months of localized tremor relief without much risk of hand weakness. And the treatment is repeatable, assuming no prior resistance to BTX from previous Botox treatments.
How injection sites are determined
A key element in this study is customization. There are various ways to identify the muscles involved in each person’s tremors. A common method is called Needle EMG Guided Injection Technique. This uses electrodes and an electrically sensitized needle guide inserted into the muscle, attached to an amplifier and a signal read-out. When the muscle is active, the amplifier produces a sound pattern. When the pattern signals muscle activity, a hypodermic needle is inserted into the needle guide, and the BTX dose is injected into the muscle. This enables tailoring the treatment to the person. To see this in action, you can watch the 9+ minute video journal of a college student with ET hand tremors who gets injections every three months. You will hear the sound of the device (like rapid clicks) as the doctor instructs her to activate specific muscles.
Repeatable vs. one-time treatment
It’s easy to understand the appeal of localized, temporary but repeatable injections to control tremor, especially for those with ET who are not helped by (or don’t want) medication. As an alternative to BTX injections, there is a new one-time noninvasive procedure called Neuravive that controls tremors at their source in the brain. If you watched the above video, you should watch at least one of the patient testimonials on our website. See for yourself the remarkable, lasting results that a single treatment provides.
ii Mittal SO, Machado D, Richardson D, Dubey D, Jabbari B. Botulinum toxin in essential hand tremor – A randomized double-blind placebo-controlled study with customized injection approach. Parkinsonism Relat Disord. 2018 Jun 12. pii: S1353-8020(18)30278-5. doi: 10.1016/j.parkreldis.2018.06.019. [Epub ahead of print]