Is efficacy of repeated intradetrusor botulinum toxin type A (Dysport®) injections dose dependent? Clinical and urodynamic results after four injections in patients with drug-resistant neurogenic detrusor overactivity

A prospective randomized clinical trial comparing two doses of AbobotulinumtoxinA for idiopathic overactive bladder

AIMS

To compare 300 U versus 500 U of abobotulinumtoxinA (ABO) intravesical injections for the treatment of idiopathic overactive bladder (OAB) refractory to first and second-line treatments.

METHODS

A prospective, randomized, single blind study was performed in female patients with symptoms of OAB, who had failed conservative treatment. Patients were treated with 300 or 500 U of ABO injected into 30 sites, avoiding the trigone. All treatments were evaluated by voiding diary, ICIQ-OAB questionnaire, urodynamic test, visual analogue scale (VAS) for treatment satisfaction and patient global impression of improvement (PGI-I). The primary outcome was change in maximum cistometric capacity (MCC). Secondary outcome included changes in urgency, complete continence, subjective success (VAS and PGI-I), and adverse events (urinary retention, UTI, and CIC).

RESULTS

Twenty-one patients were included. MCC has increased from 185.0 to 270.9 mL (300 U) and from 240.8 to 311.7 mL (500 U), comparing the baseline with 12 weeks, without statistical difference between the groups (P = 0.270). At 12 weeks, 91% of patients were dry in both groups. At 24 weeks, episodes of incontinence had returned in 50% (300 U) and 0% (500 U) (P = 0.013). Patients were better or much better (PGI-I) in70% (300 U) and 88.9% (500 U) at 12 w; and 50% (300 U) and 100% (500 U), at 24 w (P = 0.027). The peak of PVR was at 4 w, being 71.7 mL (300 U) and 96.5 mL (500 U). General UTI incidence was 35.7%. One patient (500 U) required CIC for 2 weeks.

CONCLUSIONS

Intravesical ABO injection at 500 U improves symptoms and quality of life for longer period of time than 300 U for idiopathic OAB.

Improving Outcomes in Patients With Refractory Idiopathic and Neurogenic Detrusor Overactivity: Management Strategies

Neurogenic detrusor overactivity (NDO) is a lower urinary tract dysfunction commonly seen in rehabilitation settings. The emotional, medical, and financial consequences of NDO can be substantial and management typically requires a multidisciplinary team approach. Physiatrists need to be able to identify patients who require referral to specialists for diagnostic testing or higher-tiered treatment and need to engender open lines of communication between their patients and all treating clinicians. This requires an understanding of the evaluation, diagnosis, and treatment of neurogenic lower urinary tract dysfunctions.

Efficacy and safety of the first and repeated intradetrusor injections of abobotulinum toxin A 750 U for treating neurological detrusor overactivity

PURPOSE

To assess clinical and urodynamic efficacy of the first and repeated intradetrusor injections of abobotulinum toxin A (Dysport(®), Ipsen(®), France) in patients with neurogenic detrusor overactivity (NDO) refractory to anticholinergic treatment.

METHODS

A single-center retrospective study was conducted in 81 consecutive patients who had never received any botulinum toxin intradetrusor injections. They were treated with at least one 750 U intradetrusor injection of abobotulinum toxin A. All patients performed clean intermittent self-catheterization (CIC) before injections. Success was defined as a combination of no incontinence episode, a number of catheterization <8 reported in a 3-day bladder diary and the lack of detrusor overactivity.

RESULTS

Six weeks after the first injection, the success rate was 64.2 %. The proportion of continent patients was 80.2 %, the mean number of CIC per 24 h reduced (-3.55, p < 0.0001) and the mean catheterization volume increased (+237.3 ml, p < 0.0001). Regarding urodynamics, mean maximum cystometric capacity and mean volume at the first uninhibited contraction increased (+132.7 ml, p < 0.0001 and +180 ml, p < 0.0001, respectively) and mean maximum bladder pressure decreased significantly (-21.5 cm H2O, p < 0.0001). Mean reinjection number was 3.9 and mean interval between reinjection was 8.8 ± 3 months. The clinical efficacy rate after each reinjection (up to fourteen) was at least 86.7 %. Out of 55 patients who underwent repeated injections, secondary resistance was noted in 2 (3.6 %).

CONCLUSION

The results of the present study are in favor of a long-term safety and efficacy of abobotulinum toxin A 750 U for NDO.

The use of botulinum toxin for the treatment of overactive bladder syndrome

Over the last 50 years, botulinum toxin has been transformed from a cause of life-threatening disease to an effective medical therapy. It has been used in a variety of specialties for different indications, significantly improving patient quality of life. A recent growing body of evidence suggests that intra-detrusor injection of botulinum toxin may have beneficial effects in patients with medication refractory detrusor overactivity and may offer a new minimally invasive alternative to patients with severe overactive bladder symptoms. To review current data regarding the effects of botulinum toxin in patients with overactive bladder, a MEDLINE^®/PubMed^® literature search was carried out. The mechanism of action, clinical usage, adverse effects, and treatment efficacy were reviewed and the results are presented in this paper.

Botulinum A toxin as a treatment for overactive rectum with associated faecal incontinence

AIM

Rectal hypercontractility can lead to faecal incontinence (FI). Botulinum toxin (BT) has been used successfully for the treatment of bladder overactivity. This study aimed to evaluate the therapeutic value of intrarectal injections of BT in inhibiting colorectal contractions and relieving FI in patients suffering from FI as a result of overactive rectal contractions.

METHOD

A prospective open study was carried out in Rouen University Hospital. Six patients (four men and two women) with severe FI related to overactive rectal contractions underwent intrarectal submucosal injections of BT placed in three rows of 10, 1-ml injections (50 U/1 ml; Dysport(®)) starting 1 cm above the dentate line and repeated twice, at intervals of 5 cm proximally. The end-points included improvement in the FI score, in faecal incontinence quality of life (FIQL) and of manometric abnormality.

RESULTS

All patients reported improvement in the FI score [18.2±1.1 at baseline vs 9.0±1.7 at 3 months (P=0.04)] and in FIQL. Rectal contractile activity was reduced. The frequency of contractions remained unaffected (28.1±6.6/h; P=0.46 vs baseline). High-amplitude contractions of >50 cmH(2)O were significantly decreased in all patients (16.6±3.9 vs 6.6±4.1/h; P=0.03).

CONCLUSION

Patients with an 'overactive rectum' are a heterogeneous group, with varying causes of dysfunction. The dose of BT used was arbitrarily selected. Nevertheless, the study introduces a further therapeutic option in the treatment of FI caused by rectal overactivity.

Repeat botulinum toxin-A injections for treatment of adult detrusor overactivity

Intravesical injections of botulinum toxin-A have become established as an effective therapy in the management of neurogenic and idiopathic detrusor overactivity that is refractory to treatment with anticholinergic medication. The effects of the toxin are finite and repeated injections are required to sustain the beneficial therapeutic effects. The available data suggest a reproducible and sustained improvement in symptoms as well as urodynamic parameters following repeated injections of botulinum toxin-A. The reported incidence of adverse events is low and resistance to the toxin is uncommon. The timing of repeat injections within the published data is variable, reflecting differing practise among clinicians, but is typically 6-12 months. Larger scale studies are still required to clarify the usefulness of botulinum toxin-A as a long-term treatment in the management of detrusor overactivity.

Efficacy and tolerability of botulinum toxin type A in patients with neurogenic detrusor overactivity and without concomitant anticholinergic therapy: comparison of two doses

BACKGROUND

Botulinum toxin type A (BoNTA) has been reported to be effective for treatment of patients with neurogenic detrusor overactivity (NDO) refractory to anticholinergic agents. However, in most of the studies, the efficacy was associated with concomitant use of anticholinergics.

OBJECTIVE

To evaluate the efficacy and tolerability of BoNTA and compare two different doses in patients with NDO without concomitant anticholinergics.

DESIGN, SETTING, AND PARTICIPANTS

Between 2004 and 2006, adults with NDO refractory to anticholinergics or discontinued anticholinergics due to adverse events or contraindications from four different French clinical centres were included in a prospective, randomised, double-blind, comparative trial. Inclusion criteria were urinary incontinence (UI) resulting from NDO that could not be managed with anticholinergics. Patients with bladder cancer, lithiasis, or urinary infection were excluded.

INTERVENTION

Patients were randomised to receive an intradetrusor injection of 500 U or 750 U of BoNTA.

MEASUREMENTS

The initial evaluation (ie, clinical and urodynamic variables and quality of life [QoL]) was repeated at days 30, 90, 180, and 360. Primary outcome was complete continence rate at day 30. Secondary outcomes were cumulative incontinence rate, reappearance of leakages, pad usage, urodynamics, and QoL.

RESULTS AND LIMITATIONS

Seventy-seven patients received 500 U (n=39) or 750 U (n=38) of BoNTA and were included in the full analysis set for efficacy analysis. Complete continence at day 30 was observed in 22 patients (56.4%) and 28 patients (73.7%) receiving 500 U or 750 U of BoNTA, respectively (p=0.056; one-sided χ(2) test to compare to α=0.025). The median delay in the reappearance of leakages was 168 d. Monotherapy of BoNTA significantly improved UI in patients with NDO. Although there was a trend towards a greater improvement with 750 U of BoNTA, no statistically significant differences in terms of clinical and urodynamic variables and QoL were found between the treatment groups. Tolerability was excellent and equivalent for both doses.

CONCLUSIONS

Monotherapy of BoNTA at Dysport (Ipsen, Brisbane, CA, USA) doses of 500 U or 750 U seems to be effective and well tolerated in patients with NDO.