Maximum Frown Research Articles

Dose-Ranging Study of Botulinum Toxin Type A in the Treatment of Glabellar Rhytids in Females

To compare the efficacy, safety, and duration of effect of four doses of botulinum toxin type A in the treatment of glabellar rhytids in females. Double-blind, randomized, parallel-group, dose-ranging trial followed by an open-label extension. Private dermatologic clinic. Eighty female subjects with moderate to severe wrinkles at maximum frown entered the study. The first 40 subjects completing the double-blind phase entered the open-label extension. Random administration of 10, 20, 30, or 40 U botulinum toxin type A in divided doses. Open-label trial: 30 U botulinum toxin type A at the same sites in divided doses. Trained observer and subject assessments of wrinkle severity at maximum frown and repose using the Facial Wrinkle Scale (0 = none to 3 = severe), subject satisfaction, and adverse events. Follow-up monthly for up to 1 year postinjection. Relapse rates and responder rates revealed benefits lasting 3 to 6 months or longer. Objectively, 10 U of botulinum toxin type A was significantly less effective than 20, 30, or 40 U. The relapse rate at 4 months was significantly higher in the 10 U group (83%) versus 40, 30, or 20 U (28%, 30%, and 33%, respectively). Subject satisfaction was high in all groups. Duration of effect and response rates were sustained during the open-label extension. Adverse effects were mild and infrequent. Twenty to 40 U botulinum toxin type A doses were significantly more effective at reducing glabellar lines than 10 U. Most subjects experienced benefits for 3 to 4 months; some subjects demonstrated effect for up to 12 months.

A four-month randomized, double-masked evaluation of the efficacy of botulinum toxin type a for the treatment of glabellar lines in women with skin types V and VI

Histologic differences (eg, dermal thickness, collagen fiber) among skin types of different racial/ethnic groups may affect wrinkle formation and response to treatment with botulinum toxin type A. This phase 4 study was designed to evaluate the degree and duration of effect of 20U and 30U of botulinum toxin type A for the treatment of glabellar lines in females with skin types V and VI. Females between the ages of 18 and 65 with a glabellar rhytid score of ≥2 at maximum frown on an investigator-rated, 4-point facial wrinkle scale (0 = none to 3 = severe) were eligible for the study. Patients meeting all inclusion and exclusion criteria were randomized to receive 20U or 30U botulinum toxin type A in the glabellar region. A thorough medical history was conducted at BL. The severity of wrinkles at maximum frown and repose was graded by the investigator and patient on the same 4-point scale at BL and on days 30, 60, 90, and 120. Botulinum toxin type A was administered at the assigned dose, divided among 5 equal injections, into the procerus muscle, each corrugator muscle, and each of 2 sites above the midpupillary line. Adverse events (AEs) and patient satisfaction on a 5-point scale (1 = very satisfied, 5 = very dissatisfied) were also evaluated at each visit. The primary outcome measure was the investigator’s assessment of wrinkle severity at maximum frown and repose. Responder rates were defined as the percentage of subjects with a rating of none (0) or mild (1) on the wrinkle scale. Relapse rates were the percentage of patients who returned to BL wrinkle severity at maximum frown and repose for 2 consecutive visits. Secondary outcome measures were patient assessments of wrinkle severity at maximum frown and repose, patient satisfaction, and AEs. Statistical evaluations were performed on the intent-to-treat population, and included Chi-square tests for homogenicity and linear trend. The incidence, severity, and relationship of AEs to study treatment were analyzed. Preliminary findings indicate that both 20U and 30U doses of botulinum toxin type A are safe in women with skin types V and VI. Results of this study will be reported in detail.

Botulinum toxin A (Botox Cosmetic): a review of its use in the treatment of glabellar frown lines.

Botox Cosmetic (Botox) is a formulation of the neuromuscular blocking agent botulinum toxin type A (BTX-A). When injected into hyperactive corrugator superciliaris and/or procerus muscles of the face that predominantly control frowning, Botox produces a transient (3- to 6-month), dose-dependent localized muscle weakness, resulting in a temporary improvement in glabellar frown lines ('brow furrows'). After a decade of successful 'off-label' use, the efficacy and tolerability of Botox (total dose 20 biological units) in the treatment of glabellar frown lines have been demonstrated in two identical, large, multicenter, randomized, double-blind, placebo-controlled pivotal trials in a total of 537 subjects, mostly women, with moderate or severe glabellar lines during facial animation. Based both on subjects' and physicians' assessments, the improvement in glabellar lines with Botox was superior to that with placebo at each visit during the 120-day post-injection follow-up period, beginning on day 7 post-injection. The peak effect was seen on day 30 post-injection when 80% of subjects in the two studies combined had the severity of their lines at maximum frown reduced to mild or none, as assessed by their physician, and 89% had at least a moderate (> or =50%) improvement in the appearance of their glabellar lines, as rated by themselves. In a noncomparative extension of these trials, there was a tendency for a higher proportion of subjects to respond to Botox injections after a second and third treatment session. Botox injections for glabellar lines are well tolerated. Headache, the most common adverse event, occurred with a similar frequency to placebo in the two pivotal studies (13% vs 18%). Temporary blepharoptosis occurred in 3.2% of Botox recipients; however, the incidence of this adverse event tended to decrease with repeated treatment sessions. In summary, Botox injections offer a convenient, effective, and well tolerated treatment for improving glabellar frown lines. Repeated injections are necessary to maintain a long-term effect; however, this technique clearly represents an attractive option for individuals who wish to avoid a more major procedure.

A multicenter, double-blind, randomized, placebo-controlled study of the efficacy and safety of botulinum toxin type A in the treatment of glabellar lines

Background: Botulinum toxin type A (BTX-A) is widely used for facial esthetics but is incompletely studied. Objective: This study was conducted to evaluate the efficacy and safety of BTX-A treatment of glabellar lines. Methods: Patients with moderate to severe glabellar lines at maximum frown received intramuscular injections of 20 U BTX-A (BOTOX, Allergan, Inc, Irvine, Calif) or placebo into 5 glabellar sites. Patients were followed up for 120 days after injection. Outcome measures were physician rating of glabellar line severity at maximum frown and rest, patient assessment of improvement, and vital sign and adverse event monitoring. Results: Two hundred sixty-four patients were enrolled (BTX-A: 203, placebo: 61). There was a significantly greater reduction in glabellar line severity with BTX-A than with placebo (all measures, every follow-up visit; P < .022). The effect was maintained for many patients through day 120. There was a low occurrence (5.4%) of mostly mild blepharoptosis in the BTX-A group. Conclusion: BTX-A injections are safe and effective in reducing the severity of glabellar lines. (J Am Acad Dermatol 2002;46:840-9.)