Botulinum A Toxin: Dysport Improvement of Biological Availability

doi:10.1006/exnr.2000.7583

Experimental Neurology

Volume 168, Issue 1, March 2001, Pages 162-170

https://doi.org/10.1006/exnr.2000.7583 Get rights and content

Abstract

We investigated the efficacy and potency of Dysport, a botulinum neurotoxin type A complex approved for therapy, under various conditions. Conditions for maximal expression of biological activity were explored in vitro in the phrenic nerve-hemidiaphragm preparation, while conditions for optimal distribution of the toxin were tested in vivo in a double blind trial involving volunteers, using the foot Muscles extensor digitorum brevis. In contrast to the recommendations of the manufacturer, the biological availability of Dysport could be enhanced by (1) lowering its concentration, (2) supplementing with albumin, and (3) increasing the injection volume. On the basis of these experimental findings Dysport was diluted to a final concentration of 50 U/ml for therapeutic purposes. In a blind, single crossover study patients suffering from various forms of dystonia were treated with Dysport, first diluted and dosed as suggested by the manufacturer and then with doses cut by approximately 70% in accordance with the experimental findings. The low-dose treatment was as effective as the treatment with the recommended higher doses, but side effects were considerably less apparent. The benefits to be derived from these adjustments include a low risk of antibody formation, which could preclude continued or future treatment and substantial cost savings.

References (47)

R. Eleopra et al.
Botulinum neurotoxin serotype C: A novel effective botulinum toxin therapy in humans
Neurosci. Lett.
(1997)
H. Göschel et al.
Botulinum A toxin therapy: Neutralizing and nonneutralizing antibodies—Therapeutic consequences
Exp. Neurol.
(1997)
H. Niemann
Clostridial neurotoxins—Proposal of a common nomenclature
Toxicon
(1992)
E.J. Schantz et al.
Dose standardisation of botulinum toxin
Lancet
(1990)
J.K. Tsui et al.
Double-blind study of botulinum toxin in spasmodic torticollis
Lancet
(1986)
T.J. Anderson et al.
Botulinum toxin treatment of spasmodic torticollis
J. R. Soc. Med.
(1992)
J.D. Blackie et al.
Botulinum toxin treatment in spasmodic torticollis
J. Neurol. Neurosurg. Psychiatry
(1990)
D. Boghen et al.
Effectiveness of botulinum toxin in the treatment of spasmodic torticollis
Eur. Neurol.
(1993)
G. Borodic et al.
Botulinum toxin therapy, immunologic resistance, and problems with available materials
Neurology
(1996)
G.E. Borodic et al.
Botulinum A toxin for spasmodic torticollis: Multiple vs single injection points per muscles
Head Neck
(1992)

G.E Borodic

Hemifacial spasm: Evaluation and management, with emphasis of botulinum toxin therapy

J.W.M. Brans et al.

Botulinum toxin in cervical dystonia: Low dosage with electromyographic guidance

J. Neurol.

(1995)

M.F. Brin et al.

Botulinum toxin: Dangerous terminology errors

J. R. Soc. Med.

(1991)

M.F. Brin et al.

Localized injections of botulinum toxin for the treatment of focal dystonia and hemifacial spasm

Move. Disord.

(1987)

E. Bülbring

Observations on the isolated phrenic nerve diaphragm preparation in the rat

Br. J. Pharmacol.

(1946)

A.O. Ceballos-Baumann et al.

Lokale Injektionsbehandlung mit Botulinum-Toxin A bei Blepharospasmus, Meige-Syndrom und Spasmus hemifacialis

Nervenarzt

(1990)

R. Dengler et al.

Die Behandlung von Dystonien mit Botulinumtoxin

Akt. Neurol.

(1994)

F. Dreyer et al.

Transmitter release in tetanus and botulinum A toxin-poisoned mammalian motor endplates is dependent on nerve stimulation and temperature

Pflügers Arch.

(1983)

F. Durif

Clinical bioequivalence of the current preparations of botulinum toxin

Eur. Neurol.

(1995)

J.S Elston

Management of blepharospasm and hemifacial spasm

J. Neurol.

(1992)

D.J. Gelb et al.

Controlled trial of botulinum toxin injections in the treatment of spasmodic torticollis

Neurology

(1989)

M.C. Goodnough et al.

Stabilization of botulinum toxin type A during lyophilization

Appl. Environ. Microbiol.

(1992)

P. Greene et al.

Response of botulinum toxin F in seronegative botulinum toxin A-resistant patients

Move. Disord.

(1996)

Cited by (52)

The role of human serum albumin and neurotoxin associated proteins in the formulation of BoNT/A products
2019, Toxicon
Citation Excerpt :
Thus, one MU of A/abo corresponds to one MU of A/ona as it should be expected due to the definition of MU (Schantz and Johnson, 1990; Wohlfarth et al., 1997). Other studies as well have reported that adequate concentrations of HSA are necessary for therapeutic effect of BoNT/A (Rollnik et al., 2000; Bigalke et al., 2001; Mohammadi et al., 2009). Previous in vivo studies showed even during long-term therapy that low-dose treatment with A/abo was as effective as high-dose treatment provided that the concentration of HSA was sufficient (Rollnik et al., 2000; Mohammadi et al., 2009).
Botulinum neurotoxin (BoNT) is synthesized as a progenitor toxin complex (PTC) by Clostridium botulinum. This PTC comprises, in addition to the neurotoxin itself, neurotoxin associated proteins (NAPs) which are composed of three hemagglutinins and one non-toxic, non-hemagglutinin protein. After oral ingestion, these NAPs protect the neurotoxin from the low pH and proteases in the gastrointestinal tract and play a role in the entry via the intestinal barrier. Two of the three therapeutically used botulinum neurotoxin serotype A (BoNT/A) products (onabotulinumtoxinA and abobotulinumtoxinA) contain different amounts of NAPs, while incobotulinumtoxinA, lacks these proteins. In addition, human serum albumin (HSA) that is supposed to stabilize BoNT/A is added at different concentrations. Up to now, the function of the NAPs and HSA after parenteral therapeutic application is not completely understood.
To investigate the influence of NAPs and HSA on potency of BoNT/A, we used the ex vivo mouse phrenic nerve hemidiaphragm assay.
Increasing doses of HSA resulted dose-dependently in a more pronounced effect of BoNT/A. Though, a plateau was reached with concentrations of 0.8 mg/ml HSA and higher, the accessory addition of NAPs in a relevant amount (4 ng/ml) did not further enhance the effect of BoNT/A.
In conclusion, in our ex vivo assay an adequate concentration of HSA prevented BoNT/A from loss of effect and supplementary NAPs did not alter this effect. A confirmation of these data in an in vivo assay is still lacking. However, it might be supposed that even in clinically applied BoNT/A products an increase of HSA accompanied by the avoidance of NAPs could potentially reduce the injected dose and, thus, the risk of unwanted side effects, the treatment costs as well as the risk of a secondary therapy failure due to BoNT/A neutralizing antibodies.
In-vivo comparison of the neurotoxic potencies of incobotulinumtoxinA, onabotulinumtoxinA, and abobotulinumtoxinA
2016, Neuroscience Letters
Citation Excerpt :
A possible reason for the lower potency of A/Abo may be the presence of additional proteins such as albumin in the solution for injection. Their concentrations are reduced to a greater extent due to the dilution compared to A/Ona or A/Inco [20]. A/Inco is the only BoNT/A preparation that is claimed to be free of complexing proteins and should contain only the active 150 kDa neurotoxin [4], while A/Ona and A/Abo additionally contain a 500–900 kDa protein complex [2,5].
Three botulinum neurotoxin type A (BoNT/A) products, incobotulinumtoxinA, onabotulinumtoxinA, and abobotulinumtoxinA, all manufactured by different methods, are employed in clinical practice. Comparing the three BoNT/A products is difficult because their concentrations and volumes differ and the precise dose equivalence ratio is not known. We aimed to compare the neurotoxic potencies by a systematic analysis of injected volume and dose.
The potency of BoNT in inducing hind limb paresis was assessed by analyzing the wheel-running performance of mice. To standardize the volume, the effect of an identical dose of incobotulinumtoxinA dissolved in different volumes of saline (15, 10, 5, and 2 μl) was studied in four groups of mice (n = 13–15). The potencies of the BoNT products were then compared by injecting identical volumes (10 μl) containing different doses into both hind leg muscles.
Mice injected with incobotulinumtoxinA showed a volume-dependent reduction in wheel-running, with larger volumes inducing more intense paresis. A standardized volume containing the same number of mouse units of the BoNT/A products produced different degrees of paresis. The conversion ratio of incobotulinumtoxinA and onabotulinumtoxinA is estimated to be between 1:0.75 and 1:0.5. OnabotulinumtoxinA displayed a two-fold greater potency than abobotulinumtoxinA. Doses of onabotulinumtoxinA and abobotulinumtoxinA that produce an identical severity of pareses even result in the same duration of pareses.
This wheel-running assay allows one to compare the neurotoxic potency of different volumes and doses of the BoNT products in vivo. Our results argue against common clinical practice because incobotulinumtoxinA and onabotulinumtoxinA are not readily interchangeable and a two-fold dose of abobotulinumtoxinA is needed to induce an effect identical to onabotulinumtoxinA. In addition, this emphasizes that the duration of BoNT-induced effect is the same as long as equipotent doses of BoNT are injected.
Botulinum toxin injections for the treatment of hemifacial spasm over 16 years
2015, Journal of Clinical Neuroscience
Citation Excerpt :
In HFS, side effects of BTX were usually mild and transient and improved within at most a month. Reported side effects were ptosis, facial weakness, diplopia, dry eyes, periorbital edema, epiphora, bruising and local hematoma [25,30–33,35,38,41,52,55,62–68]. Facial weakness was reported as facial asymmetry or mouth droop in different studies [27,31,69].
The aim of this study was to investigate the efficacy and side effects of botulinum toxin (BTX) in the treatment of hemifacial spasm (HFS). We also focused on the divergence between different injection techniques and commercial forms. We retrospectively evaluated 470 sessions of BTX injections administered to 68 patients with HFS. The initial time of improvement, duration and degree of improvement, and frequency and duration of adverse effects were analysed. Pretarsal and preseptal injections and Botox (Allergan, Irvine, CA, USA) and Dysport (Ipsen Biopharmaceuticals, Paris, France) brands were compared in terms of efficacy and side effects, accompanied by a review of papers which reported BTX treatment of HFS. An average of 34.5 units was used per patient. The first improvement was felt after 8 days and lasted for 14.8 weeks. Patients experienced a 73.7% improvement. In 79.7% of injections, no adverse effect was reported, in 4.9% erythema, ecchymosis, and swelling in the injection area, in 3.6% facial asymmetry, in 3.4% ptosis, in 3.2% diplopia, and in 2.3% difficulty of eye closure was detected. Patients reported 75% improvement on average after 314 sessions of pretarsal injections and 72.7% improvement after 156 sessions of preseptal injections (p = 0.001). The efficacy and side effects of Botox and Dysport were similar. BTX is an effective and safe treatment option for HFS. No difference was determined between Botox and Dysport, and pretarsal injection is better than preseptal injection regarding the reported degree of improvement.
Clostridial neurotoxins: From the cellular and molecular mode of action to their therapeutic use
2015, The Comprehensive Sourcebook of Bacterial Protein Toxins
Botulinum (BoNT) and tetanus (TeNT) neurotoxins are potent toxins responsible for flaccid and spastic paralysis, respectively. BoNTs are divided into types and subtypes according to their immunological properties and amino acid sequence variations, whereas only one type of TeNT has been characterized. BoNTs associate with nontoxic proteins to form large complexes that are resistant to acidic pH and protease degradation, unlike TeNT, which is produced as a unique protein. BoNTs and TeNT enter target neuronal cells by interacting with specific cell surface receptors. BoNTs proteolytically cleave soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins (SNAP-25, VAMP, or syntaxin) mainly at the cholinergic neuromuscular junctions impairing the evoked release of acetylcholine, whereas TeNT inhibits the neuroexocytosis in central inhibitory interneurons by cleavage of VAMP. BoNT-mediated muscle paralysis induces neuronal sprouting, which after various time periods, leads to a recovery of neurotransmission. BoNT/A, which has a long duration of activity, is used in numerous medical applications.
Establishment of alternative potency test for botulinum toxin type A using compound muscle action potential (CMAP) in rats
2014, Toxicon
Citation Excerpt :
Additionally, this method, which is lethal for mice, poses a problem with regard to animal welfare. Many alternative methods have been reported (Straughan, 2006; Hallis et al., 1996; Wictome et al., 1999; Yoneda et al., 2005; Bigalke et al., 2001; Rasetti-Escargueil et al., 2011; Aoki, 2001; Takahashi et al., 1990; Sesardic et al., 1996). In a previous report, we proposed the compound muscle action potential (CMAP) assay using rats as an alternative method to the mouse ip LD50 assay (Sakamoto et al., 2009).
The biological activity of botulinum toxin type A has been evaluated using the mouse intraperitoneal (ip) LD₅₀ test. This method requires a large number of mice to precisely determine toxin activity, and, as such, poses problems with regard to animal welfare. We previously developed a compound muscle action potential (CMAP) assay using rats as an alternative method to the mouse ip LD₅₀ test. In this study, to evaluate this quantitative method of measuring toxin activity using CMAP, we assessed the parameters necessary for quantitative tests according to ICH Q2 (R1).
This assay could be used to evaluate the activity of the toxin, even when inactive toxin was mixed with the sample. To reduce the number of animals needed, this assay was set to measure two samples per animal. Linearity was detected over a range of 0.1–12.8 U/mL, and the measurement range was set at 0.4–6.4 U/mL. The results for accuracy and precision showed low variability. The body weight was selected as a variable factor, but it showed no effect on the CMAP amplitude.
In this study, potency tests using the rat CMAP assay of botulinum toxin type A demonstrated that it met the criteria for a quantitative analysis method.
Botulinum toxins: Mechanisms of action, antinociception and clinical applications
2013, Toxicology
Botulinum toxin (BoNT) is a potent neurotoxin that is produced by the gram-positive, spore-forming, anaerobic bacterium, Clostridum botulinum. There are 7 known immunologically distinct serotypes of BoNT: types A, B, C1, D, E, F, and G. Clostridum neurotoxins are produced as a single inactive polypeptide chain of 150 kDa, which is cleaved by tissue proteinases into an active di-chain molecule: a heavy chain (H) of ∼100 kDa and a light chain (L) of ∼50 kDa held together by a single disulfide bond. Each serotype demonstrates its own varied mechanisms of action and duration of effect. The heavy chain of each BoNT serotype binds to its specific neuronal ecto-acceptor, whereby, membrane translocation and endocytosis by intracellular synaptic vesicles occurs. The light chain acts to cleave SNAP-25, which inhibits synaptic exocytosis, and therefore, disables neural transmission. The action of BoNT to block the release of acetylcholine botulinum toxin at the neuromuscular junction is best understood, however, most experts acknowledge that this effect alone appears inadequate to explain the entirety of the neurotoxin's apparent analgesic activity. Consequently, scientific and clinical evidence has emerged that suggests multiple antinociceptive mechanisms for botulinum toxins in a variety of painful disorders, including: chronic musculoskeletal, neurological, pelvic, perineal, osteoarticular, and some headache conditions.

View all citing articles on Scopus

^☆: Part of the thesis (M.D.) of A. Irmer.

²: Present address: Department of Neurology, University of Michigan, Ann Arbor, MI.

View full text

Regular ArticleBotulinum A Toxin: Dysport Improvement of Biological Availability☆

Abstract

Neurosci. Lett.

Exp. Neurol.

Toxicon

Lancet

Lancet

Botulinum toxin treatment of spasmodic torticollis

J. R. Soc. Med.

Botulinum toxin treatment in spasmodic torticollis

J. Neurol. Neurosurg. Psychiatry

Effectiveness of botulinum toxin in the treatment of spasmodic torticollis

Eur. Neurol.

Botulinum toxin therapy, immunologic resistance, and problems with available materials

Neurology

Botulinum A toxin for spasmodic torticollis: Multiple vs single injection points per muscles

Head Neck

Hemifacial spasm: Evaluation and management, with emphasis of botulinum toxin therapy

Botulinum toxin in cervical dystonia: Low dosage with electromyographic guidance

J. Neurol.

Botulinum toxin: Dangerous terminology errors

J. R. Soc. Med.

Localized injections of botulinum toxin for the treatment of focal dystonia and hemifacial spasm

Move. Disord.

Observations on the isolated phrenic nerve diaphragm preparation in the rat

Br. J. Pharmacol.

Lokale Injektionsbehandlung mit Botulinum-Toxin A bei Blepharospasmus, Meige-Syndrom und Spasmus hemifacialis

Nervenarzt

Die Behandlung von Dystonien mit Botulinumtoxin

Akt. Neurol.

Transmitter release in tetanus and botulinum A toxin-poisoned mammalian motor endplates is dependent on nerve stimulation and temperature

Pflügers Arch.

Clinical bioequivalence of the current preparations of botulinum toxin

Eur. Neurol.

Management of blepharospasm and hemifacial spasm

J. Neurol.

Controlled trial of botulinum toxin injections in the treatment of spasmodic torticollis

Neurology

Stabilization of botulinum toxin type A during lyophilization

Appl. Environ. Microbiol.

Response of botulinum toxin F in seronegative botulinum toxin A-resistant patients

Move. Disord.

Regular Article
Botulinum A Toxin: Dysport Improvement of Biological Availability☆