Novel Topical BoNTA (CosmeTox, Toxin Type A) Cream Used to Treat Hyperfunctional Wrinkles of the Face, Mouth, and Neck

Abstract

The methods used in this study are excellent, and the results are well presented. The interpretation, in agreement with the objective, describes a significant improvement in facial aging lines, particularly the hyperkinetic wrinkles and folds attributable to facial expressions and excessive muscle activity. The two groups, 20 patients in group 1 treated with CosmeTox and 20 patients in group 2 treated with placebo, are sufficient to demonstrate efficiency. The patients apply cream (1 ml) containing 2 international units (IU) of BoNTA to their faces every night for 4 to 7 weeks. The evaluation is both objective (photos and assistant experts’ review) and subjective. Both doctors and patients appreciate the results. According to the subjects’ global assessment, facial improvement of static lines and hyperkinetic wrinkles started during the 2-week period for all the patients in group 1 (25 to 50% improvement noted) and reached 85% improvement after 4 weeks for all the patients in group 1. Improvement persisted over a 12-week period. No improvement was seen in placebo group 2. In Europe, two brands of cream containing BoNTA are sold. CosmeTox seems particularly more efficient and could meet the expectations of needle-phobic patients. For other patients, it also could maintain and eventually prolong the relaxation effect for the entire face, especially the forehead, between BoNTA injections, producing a more relaxed look. The authors choose the minimum efficient dose (2 IU) for application as a topical cream every night to avoid an over-relaxing effect as well as antibody formation, which is known to be dose and frequency dependent. It would be interesting to check whether constant use of topical BoNTA cream favors the appearance of antibodies. Although eyelid ptosis is impossible with such a dose of topical BoNTA, it could nevertheless be imagined that an excessive dose might result in asymmetric eyebrow ptosis, which is totally reversible anyway. There also is the question of effective longevity with respect to the 2 IU of BoNTA. Are they still efficient as a topical cream prepared in a single 1-ml unit stored at room temperature, and for how long can it be stored in these conditions? Selection of the group 1 patients was methodical and cautious to avoid the smallest complications. The only intolerances noted were skin tightness and dryness, which were logical and predictable. I think it might be difficult in everyday clinical practice to take the necessary time and precaution before prescribing a topical cream. Another problem is the necessity of applying this cream every night and the relative impossibility of adding any other active cream containing vitamin A or C or hydrating agents during this time. An equally pertinent question concerns the cost for this type of treatment compared with well-spaced injection sessions. In conclusion, it is obvious that topical BoNTA creams cannot be superior to well-dosed and spaced BoNTA injection sessions in the right place, but my overall impression is that topical BoNTA cream (Cosmetox) will be particularly interesting for needle-phobic patients and for maintaining clinical results between injection sessions.