VIENNA, Austria-Interdigital injections of botulinum toxin type A (BTX-A, BotoxR) reportedly inhibit vasoconstriction and accelerate the rewarming process among patients with Raynaud's phenomenon (RP), according to new research presented at the Annual European Congress of Rheumatology of the European League Against Rheumatism (EULAR).1
"The effects lasted for some months," says Elke Stadlmaier, MD, rheumatologist at the Medical University of Graz in Graz, Austria. "Botox seems to be effective for the treatment of Raynaud's, so any patient suffering from Raynaud's, no matter what his or her main autoimmune disease may be, might benefit."
There were no complications or side effects-such as injection-site reactions-associated with the administration of BTX-A; however, the multiple injections are painful. "Just recently, one of my patients asked me if she might get the injection therapy by next autumn," Dr. Stadlmaier tells CIAOMed. "At least this one woman found it worth the pain of the injections."
The study included five patients-four with secondary RP due to systemic sclerosis and one patient with secondary RP associated with systemic lupus erythematosus-and two healthy controls. After 20 minutes at room temperature, participants placed their hands and forearms in ice water for 10 minutes. Researchers used an infrared camera to measure thermographic recordings before and immediately after the test, and every 5 minutes for the following 20 minutes.
After the first ice-water test, BTX-A was injected into all five digits of both hands (six sites per finger) to paralyze the muscles of the digital arteries. Patients were asked to quantify painful sensations using a visual analogue scale (VAS). Specifically, the mean VAS score was 7.4 and 5.0 before and after treatment, respectively.
The study showed a trend toward faster rewarming of the digits following the cold provocation, but hardly any change as far as the final temperature after 20 minutes. "The subjective improvement of cold-induced pain warrants further investigations of BTX-A for RP," Dr. Stadlmaier says.
BTX-A may also have a role in osteoarthritis
Research presented at the 2004 meeting of the American College of Rheumatology (ACR) showed that intra-articular injections of BTX-A decreased refractory joint pain and improved function in seven frail elderly patients with shoulder pain and five patients with refractory lower-joint pain.2 Overall, pain relief lasted 3 to 12 months, according the 1-year follow-up data.
"I have been hearing for a while about Botox for vasospasm in the hands in Raynaud's, but also in reconstructive hand surgery," says Marin L Mahowald, MD, rheumatologist at the Minneapolis Veterans Affairs Medical Center in Minneapolis, Minnesota, and lead author of the ACR study. "I am waiting to try it on the next patient with bad Raynaud's who comes in."
Dr. Mahowald tells CIAOMed that enrollment for a new randomized control trial is just about completed, and hoping [for data] that can be included in a "late-breaking" abstract at the upcoming ACR meeting. "We are re-injecting patients with Botox after it wears off, and it continues to relieve their pain," she says. "There continues to be much interest in it, and the research is going very well."
Currently, Botox is approved by the US Food and Drug Administration for the treatment of strabismus, blepharospasm, hemifacial muscle spasm, glabellar lines, and severe primary axillary hyperhidrosis.
References:
- Stadlmaier E, Müller T, Hermann J, Graninger W. Raynaud's phenomenon: treatment with botulinum toxin. Presented at: Annual European Congress of Rheumatology of EULAR; June 8-11, 2005; Vienna, Austria. Abstract FRI0060.
- Mahowald ML, Singh JA, Dykstra D. Long-term effects of intra-articular botulinum A toxin for refractory joint pain. Presented at: Annual Meeting of ACR; October 16-21, 2004; San Antonio, Tex. Presentation 1147.