Neupro Patches Placed on Shin Lessen Skin Irritation But Not Efficacy, Study Finds
Neupro patches placed on the shin caused significantly less skin irritation and itching in people with Parkinson’s’ disease who previously had site reactions when these transdermal patches were applied elsewhere, a new study has found.
The patch’s effectiveness as a dopamine agonist in easing patients’ motor symptoms was maintained while on the shin.
The study, “A Study for Expanding Application Sites for Rotigotine Transdermal Patch,” was published in the journal Parkinson’s Disease.
The Neupro patch (rotigotine, developed by UCB) is a therapy to treat people with early and advanced Parkinson’s disease.
It delivers through the skin Neupro continuously into the bloodstream over 24 hours, where it activates dopamine receptors in the brain by mimicking dopamine, which is found in lower-than-normal levels in the brain of Parkinson’s patients.
The most common side effect is application site reactions on the skin, reported in up to 44% of patients, including redness, itching, rash, and skin inflammation (dermatitis). Furthermore, up to 8% of patients have reported discontinuing the patch due to these side effects.
Six sites on the body that approved for the patch: the abdomen, shoulder, upper arm, hip, thigh, and flank.
Researchers at Kanto Central Hospital in Japan wondered if the patch could be applied at a different site to lessen such reactions while still maintaining effectiveness.
To find out, 18 women and 12 men with Parkinson’s disease, ages 63 to 86, were recruited because they had been wearing Neupro patches at approved places for more than four weeks. Their use resulted in some application site reaction.
The patch was then moved to the shin, due to ease of placing it there, for an additional four weeks.
“In this study, we aimed to assess the adequate attachment site of [Neupro patch] where application site reactions are less severe than those in six approved application sites,” the researchers said. “Then, we focused on the shin because it is very easy for the patients to attach [Neupro patch] on the shin by themselves.”
Disease duration in this group ranged from three to 15 years, and all were on stable doses of levodopa or other anti-parkinsonian medications over the four-week study period.
Their levodopa equivalent daily dose (LED) — the combined total of Parkinson’s medications — was between 448.5 mg and 1,546.5 mg, while the Neupro patch dose ranged from 4.5 mg to 31.5 mg.
Application site reactions, motor symptoms and performance, global effectiveness, and rotigotine’s blood levels were compared between the two periods, before and after switching application sites.
Application site reactions were measured using a skin irritation score, from no irritation to large blisters, and a patient-reported visual analog scale (VAS) for itching.
Results showed the itching VAS score was significantly lower after moving the patch to the shin (43.1 pre-site switch vs. 9.3 in the post-site switch). The VAS score decreased in 28 patients, increased in one, and remained unchanged in one other patient.
Skin irritation scores were also significantly reduced after switching application sites, decreasing from 0.6 before to 0.3 after. Here, the skin irritation score was lower in 19 patients; it increased in three, and was unchanged in eight others.
Motor symptoms were assessed with the Unified Parkinson’s Disease Rating Scale part III (UPDRS-III). Lower scores indicate better motor function.
UPDRS-III scores were significantly lower with shin application than other site applications (32.3 vs. 34.9), though the difference between the two groups was very small (7.4%). The UPDRS-III score diminished in 21 patients, increased in seven, and was not changed in two others.
No significant differences were seen in motor performance evaluated using the timed up and go (TUG) test — the number of the steps and the time required to rise from a chair, walk three meters, walk back, and sit down.
As assessed by a physician, a global impression of improvement was minimally improved in 11 patients, but not changed in half of these patients. It minimally worse in three, and much worse in one patient after shin application.
Rotigotine’s average blood concentration was slightly, but significantly, lower after switching sites compared to before: a difference of 9.1%. These findings may be due to differences in the medication’s absorption into the bloodstream from the shin, the researchers noted.
After the shin application, rotigotine’s concentration was lower in 19 patients, increased in two, and was unchanged in nine others. In the two patients with higher rotigotine levels, UPDRS scores were lower, whereas in the 19 patients with less rotigotine after switching, UPDRS scores were increased in seven and reduced in 12.
“In conclusion, application site reactions as assessed using the VAS scale and skin irritation score in the shin group were significantly improved compared to the approved application site group,” the researchers wrote.
The team believes that this, in combination with the small but significant observed motor improvements, indicated that “the shin can be a useful application site for [Neupro patches].”