Tailored Botox Doses Are Best Way to Treat Spasticity, Study Reports

Using a range of measures to assess cerebral palsy patients’ twitching, then adjusting the treatment to the patient, is better than giving each a commonly used standard or high dose, a study reports.

Twitching, or spasticity, is a common feature of many neurological diseases. It causes movement problems, saps a person’s self-esteem and affects their quality of life.

Doctors often prescribe botulinum toxin type A (BTX-A) — commonly known as Botox — as a spasticity treatment, and with rehabilitation. It works by reducing muscle rigidity.

A pitfall of BTX-A is that it must be tailored to a patient’s muscle properties, which doctors  assess with the modified Ashworth scale (MAS). Some cerebral palsy experts have criticized the scale, however, and contended that other muscle-evaluation methods are better.

A group of researchers decided to use a number of muscle-evaluation scales to tailor botulism treatments according to patients’ needs. Their study, ““Appropriate Treatment” and Therapeutic Window in Spasticity Treatment with IncobotulinumtoxinA: From 100 to 1000 Units,” appeared in the journal Toxins.

The research covered 120 people with spasticity. They developed the problem for different reasons — cerebral palsy, multiple sclerosis, spinal cord injuries, traumatic brain injury, stroke, and other cerebrovascular disorders.

Researchers divided them into three groups, with each receiving a different dose of IncobotulinumtoxinA. The 30 patients in group A received up to 400 units of the therapy, the 40 in group B 400-700 units, and 50 in group C 700-1,000 units.

Patients also did rehabilitation exercises every day for the first 30 days after their initial injection, then three days a week until their next injection. Each patient received four injections, with 30 days between injections.

Researchers used two scales to decide whether the treatment was working. One was an  international disability scale known as the functional independence measure. The other was a muscle-tone assessment scale known as MyotonPRO.

None of those in group A experienced significant improvements in spasticity from their treatment. When 10 of the patients moved to group B for their third injection, however, their twitching improved.

Similarly, when eight patients in group B who had experienced no improvement from their first injection were switched to group C, their spasticity improved.

All of the Group C patients’ twitching improved throughout the study.

Researchers found IncobotulinumtoxinA to be safe, even at high doses.

The study showed how important it is to assess treatment benefits from patient to patient to tailor does to individual needs. It also demonstrated that IncobotulinumtoxinA has a wide therapeutic window, with benefits accruing at doses ranging anywhere from 100 to 1,000 units.

Researchers concluded that doctors need to tailor doses to each patient’s need rather than administering a commonly used standard or high dose.