Effectiveness of repeated treatment with botulinum toxin type A across different conditions

A Multicenter Study to Evaluate Subject Satisfaction With Two Treatments of AbobotulinumtoxinA a Year in the Glabellar Lines

BACKGROUND

Real-world re-treatment intervals for botulinum toxins vary, but most subjects receive treatment less frequently than the manufacturer-recommended minimum intervals. In subjects receiving treatment with AbobotulinumtoxinA (ABO) less frequently, high levels of satisfaction and psychosocial improvements in well-being, self-confidence, and quality of life are observed.

OBJECTIVE

To evaluate subject satisfaction with a twice yearly re-treatment schedule.

METHODS AND MATERIALS

This open-label, multicenter, interventional study evaluated subject satisfaction following injections of ABO 50 U in the glabellar lines at baseline and 6 months. The primary end point was subject satisfaction at 12 months. Secondary endpoints included subject satisfaction, FACE-Q scales, and glabellar line severity scale (GLSS).

RESULTS

Ninety-five percent of the 120 subjects were "highly satisfied" or "satisfied" with their treatment outcomes at 12 months. FACE-Q total scores suggested that subjects were less bothered by glabellar lines and felt better about their facial appearance with each treatment versus baseline. Approximately half of subjects had ≥1-grade improvement from baseline in GLSS at 12 months. Median onset of effect was 2 days.

CONCLUSION

The majority of subjects (95%) were satisfied with ABO treatment every 6 months; results were supported by high subject satisfaction, long duration, rapid onset, natural-looking results, and overall psychological wellness and safety.

Repeated intrastriatal application of botulinum neurotoxin-A did not influence choline acetyltransferase-immunoreactive interneurons in hemiparkinsonian rat brain - A histological, stereological and correlational analysis

In Parkinson's disease, dopamine depletion leads to hyperactivity of cholinergic interneurons in the caudate-putamen (CPu). Botulinum neurotoxin-A (BoNT-A) inhibits the release of acetylcholine in the peripheral nervous system and is also thought to act as a local anticholinergic drug when injected intrastriatally. In hemiparkinsonian (hemi-PD) rats, a unilateral intrastriatal injection of 1 ng BoNT-A significantly diminished apomorphine-induced rotation behavior for at least 3 months, the effect fading thereafter. A second intrastriatal BoNT-A application, 6 months after the first one, led to a stronger and longer-lasting, beneficial behavioral reaction. As a single BoNT-A injection was not cytotoxic in the rat striatum and resembled BoNT-A treatment in clinical practice, here, we investigated the structural outcome of repeated intrastriatal BoNT-A injections with respect to striatal volume, the number of choline acetyltransferase-immunoreactive (ChAT-ir) interneurons and of the length of their dendritic arbors, and the numeric density of ChAT-ir BoNT-A-induced varicosities (BiVs). Repeated unilateral intrastriatal BoNT-A application decreased the volume of the injected CPu, but did not significantly change the number of striatal ChAT-ir interneurons. Also, the total dendrite length of ChAT-ir interneurons after repeated BoNT-A application resembled the values in double vehicle-injected hemi-PD rats. In repeatedly BoNT-A-injected hemi-PD rats, the numeric density of ChAT-ir BiVs in the CPu was increased compared with rats only intrastriatally injected once with BoNT-A. Even repeated BoNT-A injections in rat striata did not cause substantial morphological changes in ChAT-ir neuron, except for the increased numeric density of ChAT-ir BiVs.

Repeated Intrastriatal Botulinum Neurotoxin-A Injection in Hemiparkinsonian Rats Increased the Beneficial Effect on Rotational Behavior

Injection of botulinum neurotoxin-A (BoNT-A) into the striatum of hemiparkinsonian (hemi-PD) rats reduced apomorphine-induced rotation behavior significantly, for at least 3 months. Thereafter, rotation behavior increased again. We injected hemi-PD rats with 1 ng BoNT-A twice, the second injection following 6 months after the first one and tested the rats for apomorphine-induced rotations and spontaneous motor behaviors, i.e., corridor task and stepping test. To test the hypothesis that BoNT-A reduced striatal hypercholinism in hemi-PD rats, the acetylcholinesterase inhibitor donepezil was injected prior to separate apomorphine-induced rotation tests. In hemi-PD rats, the first BoNT-A injection led to a clear reduction of the apomorphine-induced rotations, and the second BoNT-A injection to a more massive and prolonged reaction. In hemi-PD rats whose apomorphine-induced rotation behavior was strongly reduced by an intrastriatal BoNT-A, subsequent donepezil injections led to significant increases of the rotation rate. Concerning corridor task and stepping test, neither first nor second BoNT-A injections changed hemi-PD rats' behavior significantly. The data give evidence for the possibility of repeated intrastriatal administrations of BoNT-A, for treatment of motor symptoms in experimental hemi-PD over a longer time.

Should botulinum toxin A injections be repeated in children with cerebral palsy? A systematic review

AIM

The aim of this study was to determine the effects of repeat botulinum toxin A (BoNT-A) injections in children with spastic cerebral palsy (CP) on the basis of a best evidence synthesis.

METHOD

This study included 13 original articles after searching the literature to retrieve information. We used the critical review form produced by McMaster University to determine the methodological quality of the studies, and then confirmed the levels of evidence from Sackett. The studies were also evaluated using the International Classification of Function, Disability and Health - Children and Youth Version (ICF-CY).

RESULTS

A total of 893 children with spastic CP who had been administered repeat BoNT-A injections were evaluated. The evidence level was II in four of the thirteen studies, III in four studies, and IV in five studies. The McMaster review form score was 14 in two studies, 13 in four studies, and 12 in seven studies. The results showed that repeat BoNT-A may be a safe and an effective approach. The first two injections/one repeat especially relieve spasticity and improve fine and gross motor activities.

INTERPRETATION

Future studies to investigate the effectiveness of repeat BoNT-A in children with spastic CP may be planned within the framework of the ICF-CY to include well-designed randomized controlled trials and those conducted on larger homogenous groups.

Botulinum Toxin and Muscle Atrophy: A Wanted or Unwanted Effect

While the facial rejuvenating effect of botulinum toxin type A is well known and widespread, its use in body and facial contouring is less common. We first describe its use for deliberate muscle volume reduction, and then document instances of unanticipated and undesirable muscle atrophy. Finally, we investigate the potential long-term adverse effects of botulinum toxin-induced muscle atrophy. Although the use of botulinum toxin type A in the cosmetic patient has been extensively studied, there are several questions yet to be addressed. Does prolonged botulinum toxin treatment increase its duration of action? What is the mechanism of muscle atrophy and what is the cause of its reversibility once treatment has stopped? We proceed to examine how prolonged chemodenervation with botulinum toxin can increase its duration of effect and potentially contribute to muscle atrophy. Instances of inadvertent botulinum toxin-induced atrophy are also described. These include the "hourglass deformity" secondary to botulinum toxin type A treatment for migraine headaches, and a patient with atrophy of multiple facial muscles from injections for hemifacial spasm. Numerous reports demonstrate that muscle atrophy after botulinum toxin type A treatment occurs and is both reversible and temporary, with current literature supporting the notion that repeated chemodenervation with botulinum toxin likely responsible for both therapeutic and incidental temporary muscle atrophy. Furthermore, duration of response may be increased with subsequent treatments, thus minimizing frequency of reinjection. Practitioners should be aware of the temporary and reversible effect of botulinum toxin-induced muscle atrophy and be prepared to reassure patients on this matter.

Comparative trial of a novel botulinum neurotoxin type A versus onabotulinumtoxinA in the treatment of glabellar lines: a multicenter, randomized, double-blind, active-controlled study

A novel botulinum neurotoxin type A (DWP450; Daewoong Pharmaceutical, Seoul, Korea) has recently been introduced for the treatment of facial wrinkles. The efficacy of this agent has previously been demonstrated in an in vivo study using an electrophysiological protocol in a rat model. To compare the efficacy and safety of DWP450 with onabotulinumtoxinA (OBoNT) for use in the treatment of glabellar lines, we performed a multicenter, double-blind, randomized, active-controlled trial comparing DWP450 and OBoNT (Allergan Inc., Irvine, CA, USA). A total of 268 subjects with moderate to severe glabellar lines were randomized at a 1:1 ratio. Each patient received treatment with 20 U of study medication. Maximum frown responder rates at week 4 were measured to analyze the primary efficacy endpoint. To evaluate secondary efficacy endpoints, response rates were measured at weeks 8, 12, and 16, at maximum frown and rest. Specifically, responder rates at both maximum frown and at rest were assessed based on clinical photography. Subject degree of satisfaction and self-assessed rate of response were also measured. Adverse events (AEs) were documented to evaluate safety. Responder rate by physician-rating severity at maximal contraction at week 4 was 93.89% in the DWP450 group and 88.64% in OBoNT group. As the lower limit of the 97.5% one-sided confidence interval (-1.53%) surpassed the -15% threshold, we determined that DWP450 was not inferior to OBoNT. For the secondary efficacy endpoint analyses, no significant differences were observed between the two groups for any variable at any point in time. The incidences of AEs were similar for the two groups. Most of AEs were considered mild. DWP450 and OBoNT were comparable in efficacy and safety in the treatment of glabellar lines.

Reduction of established antibody responses against botulinum neurotoxin A by synthetic monomethoxypolyethylene glycol peptide conjugates

In cervical dystonia, injection of botulinum neurotoxin (BoNT) A or B into affected neck muscle reduces symptoms but may elicit anti-toxin antibodies (Abs) that block responsiveness to treatment. Previously, we localized the BoNT/A and BoNT/B sites that bind mouse or human blocking Abs. We also reported that site-specific auto-Abs can be suppressed by a monomethoxypolyethylene glycol (mPEG)-epitope conjugate. So we elicited here anti-toxin Abs in outbred mice by immunization with sublethal-suboptimal doses of active BoNT/A and determined the efficacy of selected mPEG-epitopes in reducing established anti-BoNT/A Abs. We tested in outbred mice four synthetic mPEG-N(α)-epitopes [N8 (residues 547-565), N25 (785-803), C15 (1051-1069), C31 (1275-1296)] of BoNT/A in tolerance against ongoing anti-toxin Abs. After short immunizations, tolerization with an mPEG-peptide reduced Abs to correlate peptide and caused varying Ab reductions to the other 3 peptides. Anti-N8 Abs were unaffected by mPEG-N25 tolerization, but mPEG-N8 and mPEG-N25 caused drop in anti-BoNT/A Abs. After long immunization with BoNT/A, tolerization with mPEG-N8 lessened anti-N8 Abs. Anti-C15 Abs decreased by tolerization with mPEG-C15 or any other mPEG-peptide. Anti-N25 Abs were not altered by mPEG-N25, but decreased after tolerization with mPEG-C15. Anti-C31 Abs disappeared on day 474 by tolerization with mPEG-C31 or mPEG-N8, mPEG-N25 or mPEG-C15. When an Ab response returns, a decrease can be re-established by re-administering the correlate mPEG-peptide. The method may be beneficial for extending BoNT treatment in immunoresistant patients.

Anticholinergic therapy vs. onabotulinumtoxina for urgency urinary incontinence

BACKGROUND

Anticholinergic medications and onabotulinumtoxinA are used to treat urgency urinary incontinence, but data directly comparing the two types of therapy are needed.

METHODS

We performed a double-blind, double-placebo-controlled, randomized trial involving women with idiopathic urgency urinary incontinence who had five or more episodes of urgency urinary incontinence per 3-day period, as recorded in a diary. For a 6-month period, participants were randomly assigned to daily oral anticholinergic medication (solifenacin, 5 mg initially, with possible escalation to 10 mg and, if necessary, subsequent switch to trospium XR, 60 mg) plus one intradetrusor injection of saline or one intradetrusor injection of 100 U of onabotulinumtoxinA plus daily oral placebo. The primary outcome was the reduction from baseline in mean episodes of urgency urinary incontinence per day over the 6-month period, as recorded in 3-day diaries submitted monthly. Secondary outcomes included complete resolution of urgency urinary incontinence, quality of life, use of catheters, and adverse events.

RESULTS

Of 249 women who underwent randomization, 247 were treated, and 241 had data available for the primary outcome analyses. The mean reduction in episodes of urgency urinary incontinence per day over the course of 6 months, from a baseline average of 5.0 per day, was 3.4 in the anticholinergic group and 3.3 in the onabotulinumtoxinA group (P=0.81). Complete resolution of urgency urinary incontinence was reported by 13% and 27% of the women, respectively (P=0.003). Quality of life improved in both groups, without significant between-group differences. The anticholinergic group had a higher rate of dry mouth (46% vs. 31%, P=0.02) but lower rates of catheter use at 2 months (0% vs. 5%, P=0.01) and urinary tract infections (13% vs. 33%, P<0.001).

CONCLUSIONS

Oral anticholinergic therapy and onabotulinumtoxinA by injection were associated with similar reductions in the frequency of daily episodes of urgency urinary incontinence. The group receiving onabotulinumtoxinA was less likely to have dry mouth and more likely to have complete resolution of urgency urinary incontinence but had higher rates of transient urinary retention and urinary tract infections. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Institutes of Health Office of Research on Women's Health; ClinicalTrials.gov number, NCT01166438.).

Care management of spasticity with botulinum toxin-A in patients with severe acquired brain injury: a 1-year follow-up prospective study

OBJECTIVE

To evaluate the efficacy and the safety of repeated botulinum toxin type A (BT-A) injections in patients with severe acquired brain injury (ABI) and to gain a better knowledge of possible clinical or demographic characteristics associated with a better rehabilitation outcome.

DESIGN

Prospective study with a 1-year follow-up period.

SUBJECTS

Twenty-one patients with spasticity due to severe ABI and no further improving with rehabilitation treatment and oral anti-spastic drugs.

INTERVENTION

Repeated BT-A injections associated to a rehabilitation programme.

MAIN MEASURES

Barthel Index (BI), Modified Ashworth Score (MAS) and VAS score for pain subjective perception were recorded.

RESULTS

At the end of the follow-up study, MAS, BI and VAS significantly improved. Despite the number of BT-A injections, a shorter interval between severe ABI onset and first BT-A treatment correlated to a better BI improvement. None of the patients experienced adverse events attributable to BT-A.

CONCLUSION

BT-A was effective and safe in the treatment of spasticity in severe ABI patients, with a better functional outcome in those subjects treated earlier after spasticity onset. The lack of correlation between clinical outcome and number of injections suggests, in addition to a direct inhibition at the neuromuscular junction, a more distant BT-A long-term effect.

Anticholinergic versus botulinum toxin A comparison trial for the treatment of bothersome urge urinary incontinence: ABC trial

This trial compares the change in urgency urinary incontinence episodes over 6 months, tolerability and cost effectiveness between women receiving daily anticholinergic therapy plus a single intra-detrusor injection of saline versus a single intra-detrusor injection of 100 U of botulinum toxin A plus daily oral placebo tablets. We present the rationale and design of a randomized-controlled trial, Anticholinergic versus Botulinum Toxin, Comparison Trial for the Treatment of Bothersome Urge Urinary Incontinence: ABC trial, conducted by the NICHD-funded Pelvic Floor Disorders Network. We discuss the innovative nature of this trial and the challenges related to choice of patient population, maintaining masking, cost effectiveness, ethical considerations, measuring adherence, and placebo development and testing. Enrollment began in April, 2010. 242 participants will be randomized and primary outcome data analysis is anticipated to begin in mid 2012. Several challenges in the trial design are discussed. Randomization to placebo intra-detrusor injections may limit recruitment, potentially impacting generalizability. Other challenges included the heavy marketing of drugs for overactive bladder which could impact recruitment of drug-naïve women. In addition, anticholinergic medications often cause dry mouth, making masking difficult. Finally, adverse reporting of transient urinary retention is challenging as there is no standardized definition; yet this is the most common adverse event following intra-detrusor botulinum toxin injection. The ABC trial will help women with urgency urinary incontinence balance efficacy, side effects and cost of anticholinergic medication versus botulinum toxin intra-detrusor injection. The results have the potential to fundamentally change the therapeutic approach to this condition.

Botulinum toxin: examining duration of effect in facial aesthetic applications

Patient satisfaction with botulinum toxin treatment is a key success factor in aesthetic procedures and is governed by the interaction of numerous variables. Duration of effect is important because it influences retreatment intervals as well as affecting cost and convenience to the patient. In order to review the evidence on the duration of benefit associated with various commercial formulations of botulinum toxin, MEDLINE was searched using the following terms: 'botulinum' and 'duration'/'retreatment' (limits: 'clinical trials,' 'meta-analyses,' 'English'). I also searched my existing reference files, reference lists of identified articles, and meeting/conference abstracts to ensure completeness. The focus was on clinical medicine and aesthetic trials. To be eligible for the analysis, studies had to include efficacy assessments at multiple timepoints. To estimate duration of benefit, the following outcomes were examined and summarized: responder rates, mean wrinkle severity scores at various timepoints (with or without changes from baseline), and relapse rates. Duration at both repose and maximum attempted muscle contraction was considered when provided. Where possible, duration was assessed by formulation and dose. The initial search yielded 164 articles. Of these, 35 included an adequate measure of duration in aesthetic indications. The majority of these (22) were on the glabellar area. Study designs and endpoints were highly heterogeneous, and duration of effect varied between studies. Several studies with the BOTOX Cosmetic (onabotulinumtoxinA; Allergan, Inc., Irvine, CA, USA) formulation of botulinum toxin type A (BoNTA) included relapse rates, defined conservatively as return to baseline levels of line severity for two consecutive visits approximately 30 days apart (at repose and maximum contraction). In these studies, duration of effect ranged from 3 to 5 months in female patients and from 4 to 6 months in male patients. Individual patients had longer durations of response. Across all studies providing relapse rates, most patients relapsed by 6 months. In studies assessing patient satisfaction, satisfaction remained high throughout the duration of the studies ( approximately 4 months). With the Dysport formulation (abobotulinumtoxinA, clostridium botulinum type A toxin-hemagglutinin complex; Ipsen Biopharm Ltd, Wrexham, England), retreatment intervals were estimated at a mean of 3.9 months (median = 3.3 months). These results were consistent with responder rates from another Dysport study in which the active treatment differed from placebo at 3 but not 4 months. A single comparative study demonstrated that the proportion of patients relapsing at week 16 was 23% (95% CI 11.5, 41.6) in the BOTOX Cosmetic group as compared with 40% (95% CI 25.2, 60.1) in the Dysport group. Myobloc (rimabotulinumtoxinB, botulinum toxin type B; Solstice Neurosciences, Inc., South San Francisco, CA, USA) was associated with shorter durations of action (2-3 months). Data from facial areas other than the glabella, although more limited, supported a duration of at least 3-4 months. The addition of BoNTA to dermal fillers or light/laser therapy appeared to increase the degree of effect. Repeated BoNTA treatments may prolong duration of effect or potentiate the effect. In conclusion, patients can expect treatments to last > or =3 months but often as many as 4-5 months depending on the facial area, dose, and formulation. Additional research should help clarify the impact of age, baseline rhytid severity, patient sex, repeated treatments, and combination treatment on longevity of effect.

An open-label, randomized, 64-week study repeating 10- and 20-U doses of botulinum toxin type A for treatment of glabellar lines in Japanese subjects

BACKGROUND

Repeated botulinum toxin type A (BoNTA) treatment typifies clinical practice. The long-term safety and efficacy should be demonstrated in diverse populations.

OBJECTIVE

To evaluate the long-term efficacy and safety of repeated BoNTA treatments of glabellar lines in Japanese subjects.

METHODS

This randomized, multicenter, 64-week, open-label study of 363 subjects compared 10-U and 20-U of BoNTA for up to five treatments. The endpoints were the physician ratings of line severity and duration of efficacy, and subject ratings of line improvement and satisfaction. Safety assessments included adverse events, laboratory tests, and vital signs. Tests for neutralizing antibodies were conducted.

RESULTS

Peak response rates (> 90%, maximal contraction) were observed at week 1 (treatment 1) and week 4 (treatments 2-5). The duration did not change with repeated treatments and was longer in the 20-U than in the 10-U group (17.1 +/- 6.58 weeks vs. 14.8 +/- 5.38 weeks; P < 0.001). Subject-assessed improvement ratings, 4 weeks' post-treatment, were significantly higher ( P < or = 0.05) in the 20-U group. Overall satisfaction ratings were significantly higher in the 20-U group ( P < 0.001). No serious adverse events occurred. Neutralizing antibodies were not detected.

CONCLUSION

Repeated treatments of glabellar lines with 10 or 20 U of BoNTA provided long-term safety and efficacy in Japanese subjects. The 20-U dose provided longer duration, greater subject satisfaction, and greater subject-rated improvement. The 20-U dose was identified as optimal for improving glabellar lines in Japanese subjects. These results apply only to the formulation of BoNTA used in this study.

Long-term treatment with botulinum toxin type A in cervical dystonia has low immunogenicity by mouse protection assay

To evaluate the immunogenicity of botulinum toxin type A (BoNTA; BOTOX) in cervical dystonia (CD). Subjects diagnosed with CD for > or =1 year and previously naïve to BoNTs were treated with BoNTA in a prospective, open-label, multicenter study. Serum samples were analyzed for BoNTA neutralizing antibodies using the Mouse Protection Assay (MPA). Clinical resistance was assessed with a test injection of 20 U BoNTA placed unilaterally into the frontalis (Frontalis Antibody Test; FTAT) or corrugator muscle (Unilateral Brow Injection; UBI). Efficacy was assessed and adverse events were recorded. Of 326 subjects enrolled, 251 (77%) completed the study. Subjects received a median of 9 BoNTA treatments (mean dose per session ranged from 148.4 to 213.0 U over a mean of 2.5 years [range: 3.2 months-4.2 years]). Only 4 of 326 subjects (1.2%) tested positive for antibodies in the MPA; three of these subjects stopped responding clinically to BoNTA (of whom one also showed clinical resistance in the FTAT) and one continued to respond. Consistent improvements in the signs/symptoms of CD were noted. The most frequent treatment-related adverse events were mild to moderate weakness, dysphagia, neck pain, and injection-site pain. The current formulation of BoNTA rarely causes neutralizing antibody formation in CD subjects treated < or =4 years.

A double-blind, randomized, placebo-controlled, two-dose comparative study of botulinum toxin type A for treating glabellar lines in Japanese subjects

Background

Systematic, well-controlled clinical trials of botulinum toxin type A (BoNTA) in diverse patient populations are needed. The aim of this study was to characterize the safety and efficacy of 10-U and 20-U BoNTA doses versus placebo for treating glabellar lines in Japanese subjects.

Methods

A 16-week, multicenter, double-blind, randomized, placebo-controlled trial comparing 10 or 20 U of BoNTA versus placebo in 142 Japanese subjects with glabellar lines of at least moderate severity at maximal contraction. The primary efficacy endpoint was physician-rated line severity at maximal contraction 4 weeks after treatment. Secondary efficacy endpoints included physician/subject ratings and estimates of the effect’s duration.

Results

Response rates by physician-rated line severity at maximal contraction (week 4) were 86.4% (10 U), 88.6% (20 U), and 0% (placebo, p < 0.001). Line severity at maximal contraction in each BoNTA group (p < 0.001) improved significantly from baseline at each visit. BoNTA and placebo differed significantly on all other efficacy measures. Mean duration of effect was 9.4 weeks in the 20-U group and 7.9 weeks in the 10-U BoNTA group. No serious adverse events occurred.

Conclusion

Doses of BoNTA of 10 and 20 U are effective and safe for treating glabellar lines in Japanese subjects, and the 20-U dose provides greater efficacy and longer duration of effect.