Evaluation of the Efficacy of the Injection of Botulinum Toxin A vs Scopolamine Patches in the Treatment of Drooling in Children With Cerebral Palsy

Cerebral palsy is the first cause of motor disability in developed countries. It is associated with altered motor function but also with mental, sensorial and behavior deficiencies. Drooling frequently occurs in children with cerebral palsy (37 to 58%). It causes multiple medical and social complications which can all increase disability and reduce quality of life for the patients and their family. Drooling treatments are various and includes orofacial rehabilitations, anticholinergic medications, botulinum toxin A and B salivary gland injections. Surgeries could also be used, but their benefits are often outweighed by the risk.

• Orofacial rehabilitation is firstly recommended, even if few studies evaluated its efficacy.

• Medication by Scopoderm®, a cutaneous anticholinergic drug, is frequently used in spite of frequent side effects and a lack of evidence regarding efficacy.

• Botulinum toxin salivary gland injections (Botox®) were shown to be effective in reducing the severity of drooling consequences for the patient quality of life up to 12 months after the injections (Reid 2008).

A recent survey carried showed that treatment by Botox® injection would be preferred by professional to Scopoderm® patch, because of better tolerance and efficacy, even if Scopoderm® remained more used by professionals (Chaleat-Valayer 2016). However, a Cochrane review (Walshe 2012) concluded that there is 1) no strong consensus regarding assessment or the timing of all treatments 2) not enough efficacy studies with high level of evidence, 3) mostly efficacy studies vs placebo or no intervention 4) a lack of long term treatment assessment 5) a lack of studies on the patient quality of life.

Our study will be a comparative randomized clinical trial with an active control arm. The hypothesis is that therapeutic treatment of drooling in children with cerebral palsy consisting of a standardized rehabilitation treatment associated with a botulinum toxin A injection (Botox®) in the salivary glands is more effective than the same rehabilitation treatment associated with a treatment by scopolamine patches (Scopoderm®).

The main outcome will be assessed 15 months after initiation of treatment to evaluate long-term effectiveness. Patients from both arms of the trial will received rehabilitation, in order to compare treatment efficacy as it is done in real conditions of treatment. The efficacy of the treatment will be assessed on the impact of the drooling perceived by the patients and their family rather than on the measure of salivary production, as recommended (Walshe 2012).