Funding is no longer available

Raynaud's phenomenon (RP) is a common vascular disorder that affects approximately 10% of the general population. RP is associated with significant morbidity that may include loss of the digits due to repeated episodes of vasospasm of the digital arteries in addition to significant impairment of quality of life. It is well known that cold exposure precipitates episodes of RP, but the mechanism for cold sensitivity is not known, and treatment of RP is not satisfactory to the patients and their physicians.

The goal in this study is to test the possibility that non invasive vagus nerve stimulation (nVNS) with gammaCore which is already approved by the FDA for headaches and migraines may be an effective and well tolerated therapy for Raynaud's Phenomenon.

Raynaud's phenomenon (RP) is a common vascular disorder that that affects approximately 10% of the general population. RP causes some areas of the body (i.e. fingers and toes) to feel cold and numb in response to cold exposure or emotional stress. Raynaud's phenomenon is characterized by reversible vasospasm of the fingers and toes. This reversible narrowing of the small arteries induces episodes of color changes of the fingers and toes. During an attack of Raynaud's, affected areas of the skin usually first turn white, then they often turn blue and feel cold and numb (pins and needles). As the fingers warm and circulation improves the affected areas may turn red, throb and tingle.

Moreover, Raynaud's phenomenon can be associated with significant morbidity that may include ulceration of fingers and loss of the fingers and toes due to repeated episodes of reversible narrowing of arteries supplying blood to the finger and toes. It is well known that cold exposure leads to episodes of RP, but the mechanism for cold sensitivity is not known, and treatment of RP is not satisfactory to the patients and their physicians.

Raynaud's phenomenon is classified as Primary Raynaud's phenomenon (PRP) in the absence of other vascular or connective tissue disease. Raynaud's phenomenon is classified as Secondary Raynaud's phenomenon (SRP) if it is associated with connective tissue disease, like systemic sclerosis (SSc, Scleroderma).

Treatment of Raynaud's phenomenon is not satisfactory in general, as current therapy employing calcium channel blockers and other vasodilators are frequently ineffective or not well tolerated, due to significant side effects.

Noninvasive vagus nerve stimulation (nVNS) is currently FDA approved for therapeutic uses in patient ages 12 and above to treat cluster and migraine headaches. Recent studies have shown that vagal nerve stimulation has vasodilatory and anti-inflammatory properties which has led to more preclinical research examining vagus nerve stimulation as treatment for a wider range of inflammatory and autoimmune disorders. Vagus nerve stimulation has shown promising results in treating chronic inflammatory disorders such as sepsis, lung injury, rheumatoid arthritis, and diabetes. Although there are no direct data to demonstrate vagus nerve stimulation's effect in Raynaud's phenomenon, the investigators believe that VNS's success in treating headache and migraine attacks indirectly support its use in Raynaud's phenomenon by its direct effect on vasospasms (narrowing of blood vessels). In fact migraine has been found as a risk factor for the development of Raynaud's phenomenon further supports this notion.

GammaCore is a safe and effective non-drug treatment approved for treating cluster and migraine headaches. It is a patented device that activates the vagus nerve with gentle electrical stimulation. The vagus nerve is an important highway of communication between the brain and many parts of the body, it plays an important role in regulating pain. Noninvasive vagus nerve stimulation with GammaCore is believed to help block the pain signals that cause migraines and cluster headaches. Unlike traditional vagus nerve stimulation therapies, gammaGore stimulates the vagus nerve through the skin at the side of the neck without the need for surgery. This non-invasive method avoids many side effects and inconveniences associated with injectable, inhaled or pill-based medication.

The investigators' goal is to test the possibility that noninvasive vagus nerve stimulation using gammaCore may be an effective and well tolerated therapy for Raynaud's phenomenon. The investigators aim to gain a fundamental understanding of the role of noninvasive vagus nerve stimulation as a potential therapy for Raynaud's phenomenon, a truly unmet medical need.

Inclusion Criteria:

• Clinical Diagnosis of Primary Raynaud's Phenomenon

Exclusion Criteria:

• Less than 18 years of age
• Pregnant women
• Current smokers
• Have Digital ulcers
• Diagnosed Pulmonary hypertension
• Currently on vasodilators (i.e. Phosphodiesterase type 5 inhibitors, prostacyclin, nitroglycerine, or other nitric oxide derivatives)
• Currently on Calcium Channel Blockers

Subjects randomized to the Experimental group will use the gammaCore Sapphire till the end of the study. Subjects in this group will become un-blinded in the open label phase of the study at 4 weeks after randomization.

Subjects randomized to the Sham group will use the Sham device for 4 weeks. Subjects in the Sham group will become un-blinded in the open label phase of the study at 4 weeks after randomization and be switch to the gammaCore Sapphire for the rest of the study.