Efficacy of Botulinum Toxin In Scleroderma-Associated Raynaud's Syndrome

A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial Assessing the Therapeutic Efficacy of Botulinum Toxin In Treating Scleroderma-Associated Raynaud's Syndrome

This is a randomized, double-blinded, clinical trial assessing the therapeutic efficacy of Botulinum toxin A (Onabotulinumtoxin A) in treating scleroderma-associated Raynaud's syndrome. Each patient will undergo injection with a treatment dose of Botulinum toxin A in one randomly-selected hand, and the contralateral hand will be injected with sterile saline (placebo) to serve as a control. Study participants at the first study visit will complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging to assess blood flow. After this initial assessment, the patients will undergo peri-arterial injection of Botulinum toxin A in one hand, and of sterile saline solution (placebo) in the other, in a randomized, blinded manner. Patient will report the severity of their Raynaud's symptoms weekly over the four month study period. At one month post-injection, the patient will complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging. At four months post-injection, the patient will again complete study questionnaires, their hands will be assessed clinically for digital ulceration, and their hands will undergo non-invasive laser Doppler imaging. In addition, patient will be given the option of one week post-injection visit, at which point the same assessment will be performed. At the conclusion of the study, unblinding will occur.

One hand of each patient will be randomly selected for injection of Botulinum Toxin A (Onabotulinumtoxin A, 20 units/mL). Injections are performed using a 30 gauge insulin syringe through the dorsal surface in seven locations: adjacent to the 2nd, 3rd, and 4th common digital arteries through the web spaces (10 units each=0.5mL each), and the radial side of the index finger metacarpal head, the ulnar side of the small finger metacarpal head, and each side of the thumb metacarpal head (5 units each= 0.25mL each). Total treatment dose of Botulinum Toxin A will not exceed 50 units per hand.

One hand of each patient will be randomly selected for injection of sterile saline solution (placebo). Injections are performed using a 30 gauge insulin syringe through the dorsal surface in seven locations: adjacent to the 2nd, 3rd, and 4th common digital arteries through the web spaces (0.5 mL each), and the radial side of the index finger metacarpal head, the ulnar side of the small finger metacarpal head, and each side of the thumb metacarpal head (0.25 mL each).

The primary outcome measure is change in blood flow to the fingers, from a pre-injection baseline to post-injection follow-up visit as measured by non-invasive laser Doppler imaging.

Raynaud's Condition Score is a patient-reported, validated outcomes scale that measures the severity of Raynaud's phenomenon on a scale of 0 ("No difficulty") to 10 ("Extreme difficulty"), where higher values represent a worse outcome. Data from each weekly report were combined using a statistical model (generalized linear population-average model) to calculate a weekly rate of change for each participant's hand, where a negative value represents a improvement over time and a positive value represents worsening over time.

A secondary outcome of this study is the number of digital ulcers as determined by clinical examination. Mean number of ulcers was calculated as total number of ulcers / total number of hands in each group.

A secondary outcome of this study is severity of Raynaud's symptoms as measured by the self-reported Quick-DASH score. The Quick-DASH scores measures the degree of hand and upper extremity function on a scale of 0 (not limited) to 100 (severely limited) where a higher value represents a worse outcome.

A secondary outcome of this study is the patient-reported sensitivity to coldness as measured by the McCabe Cold Sensitivity score. Patients' answers on this validated instrument are scored on a scale from 0 (no sensitivity) to 400 (extreme sensitivity), where a higher number represents a worse outcome.

A secondary outcome of this study is pain as measured by the validated visual-analog scale (VAS) for pain. The VAS pain instrument measures pain on a scale from 0 cm (no pain) to 10 cm (extreme pain)

Inclusion Criteria: Aged 18 years and older Diagnosed with scleroderma. Symptoms of Raynaud's syndrome affecting both hands (not necessarily to equal extents) Ability to return/be available for follow-up evaluations Able and willing to give informed consent Able to speak and read in the English language. Exclusion Criteria: A history of Myasthenia gravis. Reported allergy or hypersensitivity to any Botulinum toxin preparation. Active infection in either hand. Patients who have ever received Botulinum toxin vaccine. Pregnant or lactating women. Females unable or unwilling to maintain abstinence or use contraception for 28 days following the injections. Patients who have previously undergone any vascular surgery on the upper extremity, including surgical sympathectomies. Current use of any aminoglycoside antibiotic

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Bello RJ, Cooney CM, Melamed E, Follmar K, Yenokyan G, Leatherman G, Shah AA, Wigley FM, Hummers LK, Lifchez SD. The Therapeutic Efficacy of Botulinum Toxin in Treating Scleroderma-Associated Raynaud's Phenomenon: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. Arthritis Rheumatol. 2017 Aug;69(8):1661-1669. doi: 10.1002/art.40123. Epub 2017 Jun 26.