Botulinum Toxin Type A for Facial Wrinkles
Camargo CPires, Xia J, Costa CS, Gemperli R, Tatini MDC, Bulsara MK, RieraR. Botulinum toxin type A for facial wrinkles. Cochrane Database of Systematic Reviews 2021, No. 7. Art. No.: CD011301. doi: 10.1002 /14651858.CD011301.pub2. Accessed August 1, 2021.
DESCRIPTION
This study was conducted to evaluate the efficacy of all commercially available botulinum toxin type A products used in the treatment of all types of facial wrinkles.
The main results reviewed included 65 RCTs involving 14,919 randomized participants, participants were women aged 18-65 years, outpatients (private clinics or day clinics), and study duration ranged from 1 week to 1 year.
No study was rated as having a low risk of bias in all domains, and the overall risk of bias was largely equivocal.
The most common comparator was placebo medication, active control was used in 19 studies, onabotulinumtoxinA was used in 8 dose-ranging studies, and a small number of studies compared it with filler.
Treatments were given in one cycle (54 studies), two cycles (three studies), and three or more cycles (eight studies).
Treatment areas included the area between the eyebrows (43 studies), crow's feet (7 studies), forehead (2 studies), perioral area (2 studies), full face (1 study), and two or more areas (9 studies).
Most of the studies analyzed moderate to severe wrinkles, with an average treatment duration of 20 weeks.
Compared to placebo, onabotulinumtoxin A-20 U may have a higher success rate when evaluated by participants and by physicians. Major AEs were higher with onabotulinumtoxin A-20 U, but there may be no difference in any AEs.
Compared to placebo, avobotulinumtoxin A-50 U has a higher success rate as assessed by participants and physicians at week 4.
Also, compared to placebo, incobotulinumtoxin A-20 U had a higher success rate as assessed by participants and physicians at week 4, but no major AEs were observed. Therefore, there may be no difference between the groups in any AE.
Avobotulinumtoxin A-50U did not have a significantly higher success rate as assessed by the participants and physicians, and was more likely to occur in the avobotulinumtoxin A-50U group than in the onabotulinumtoxin A-20U group.
IncobotulinumtoxinA-24U may not differ from onabotulinumtoxinA-24 U in the success rate of physician assessment at week 4.
Compared to placebo, daxivotulinumtoxin A-40 U did not significantly differ in the success rates of participant and physician assessments, and no major AEs were observed. There may be an increase in AEs with daxibotulinumtoxin A compared to placebo.
The major AEs reported were mainly eyelid drooping, and BontA is also known to be associated with a risk of strabismus and eyelid paresthesias.
The authors conclude that
BontA treatment reduces wrinkles within 4 weeks of treatment, but probably increases the risk of ptosis. We found several heterogeneous studies (different types or doses of BontA, number of cycles, and different facial areas) that preclude a meta-analysis. The certainty of evidence for efficacy results was high, low, or moderate; for AEs, very low to moderate. Future RCTs should compare the most common BontA (onabotulinumtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, daxibotulinumtoxinA, prabotulinumtoxinA) and evaluate the long-term results. There is no evidence on the effect of multiple cycles of BontA, frequency of major AEs, duration of effect, efficacy of the recently approved BontA, and comparison with other therapies.
