Dutch researchers have linked a group of rheumatoid arthritis drugs to skin problems.
Humira (adalimumab), Remicade (infliximab), and Enbrel (etanercept) are mentioned in the study, which appears in the journal Arthritis Research and Therapy.
All of those medications are biologic treatments for rheumatoid arthritis. They are a new type of treatment approach that inhibits TNF, a chemical made by the body to induce inflammation. These chemical substances lead to joint inflammation seen in RA.
The study “shows that dermatological conditions are a significant and clinically important problem in RA patients receiving TNF-alpha-blocking therapy,” write the researchers.
Out of 289 RA patients taking biologic agents, 72 (25 percent) consulted a dermatologist about skin problems over an average of two years. In comparison, in a group of RA patients who had never received these drugs, 37 (13 percent) consulted a dermatologist. The comparison group tended to have less severe cases of RA, say the researchers.
Most Common Problems
There were a total of 128 skin problems among the 72 patients taking biologic agents who had consulted a dermatologist. Their most common conditions were skin infections (33 cases), eczema (20 cases), and drug-related skin eruptions (15 cases). None required hospitalization but seven patients decided to stop taking the drugs because of skin problems.
The number of skin problems reported during or after treatment was 56 for Humira, 49 for Remicade, and 16 for Enbrel, write the researchers, who included Marcel Flendrie of Radboud University Njimegen Medical Centre in the Netherlands.
Most of the skin eruptions occurred in the first five months of treatment with the biologic agents and were caused by all of the drugs, the researchers report. Reports of skin problems had surfaced in study trials of the drugs but this is the first large study that tracked problems as they unfolded, say Flendrie and colleagues.
Who Took What Drugs
The group included 70 patients who were taking more than one TNF blocker. Eight patients took more than two anti-TNF drugs, say researchers.
Humira was taken by 108 patients, Remicade by 167, and Enbrel by 78 people.
Drug Companies Respond
“Based on the information in the article, we really can’t address [the study],” says Candace Steele, director of global public relations for Wyeth Pharmaeuticals, which markets Enbrel in the U.S. together with the drug company Amgen.
“I can tell you that we have seen dermatological effects with some patients who’ve used Enbrel,” says Steele. “Essentially, if a physician were to contact us about dermatological effects, we have standard information [stating that] skin rash has been described in clinical trials, postmarketing experience, and literature reports.”
Patients should report any skin conditions to their doctors, she adds.
“Injection site reaction is a possible side effect that’s listed in our label. In fact, it’s in the label of all TNF inhibitors,” says Jim Bozikis, manager of pharmaceutical public affairs for Abbott Laboratories, which makes Humira.
“Our experience with RA patients and Humira is that when side effects do occur, they’re so mild that patients choose to continue therapy because the benefits greatly outweigh any side effects,” he says.
“In general, with anti-TNF therapy, patients are more susceptible to infection and the key is for patients to work closely with their physicians and carefully monitor their progress,” says Bozikis.
SOURCES: Flendrie, M. Arthritis Research and Therapy, April 3, 2005. News release, BioMed Central. Candace Steele, director, global public relations, Wyeth Pharmaceuticals. Jim Bozikis, manager, pharmaceutical public affairs, Abbott Laboratories.