Arthritis drug linked to skin disorders

Last updated at 08:57 04 April 2005

Drugs used to treat patients with severe rheumatoid arthritis can trigger serious skin disorders, a study has claimed.

Researchers looked at the class of drugs known as Tumour Necrosis Factor (TNF) alpha blockers which are used in the most serious cases of rheumatoid arthritis (RA).

They work by switching off TNF, which stimulates cells to produce the inflammation response that leads to pain and swelling of the joints.


The team from the Radboud University Nijmegen Medical Centre in the Netherlands found in many patients the powerful drugs could cause skin conditions such as eczema and skin tumours.

But the Arthritis Research Campaign said the benefits of treatment with TNF blockers far outweighed the risks in patients with serious RA.

The research follows last year's withdrawal of the pain-killing drug Vioxx, also used to treat arthritis patients, after it was linked to an increased risk of heart attack and stroke.


Further studies also reported possible higher risks with other drugs in the same family, known as COX-2 inhibitors.

The latest research, published in the journal Arthritis Research and Therapy, followed 289 patients who had treatment for RA with TNF blockers for between one and 10 years.

The drugs the patients were taking included two anti-TNF-alpha antibodies - infliximab and adalimumab - and the TNF-alpha receptors etanercept and lenercept.

The researchers found that 25% of patients on the therapy suffered from a dermatological condition that led them to visit a skin specialist.

But in a control group of patients not using TNF blockers and with less severe disease, only 13 per cent visited a dermatologist during the same period.

The most frequently reported skin conditions among those on the therapy were skin infections (33 cases) and eczema (20 cases).

Twelve patients were diagnosed with skin tumour and nine with an ulcer.

Overall 26 per cent of patients who developed a skin condition ceased their treatment due to the problem.

'Significant problem'

The researchers concluded: "Dermatological conditions are a significant and clinically important problem in rheumatoid arthritis patients on TNF-alpha blocking therapy."

They noted that conditions such as skin infections were common in RA patients.

But they said that the use of TNF blockers might increase susceptibility because TNF-alpha was a major player in the immune response to infections.

The researchers also said that down-regulating TNF-alpha may also trigger another type of immune response, which increases susceptibility to eczema which is not usually associated with RA.

RA affects more than 400,000 people in the UK, causing inflammation of multiple joints, cartilage loss and bone erosion and leading to joint destruction.

It can also affect other tissues, such as the lungs, eyes and bone marrow

Dr Madeleine Devey, scientific officer at the Arthritis Research Campaign, said in the UK TNF blockers were only used in patients who had failed on treatment with at least two other drugs, such as steroids.

She said they were used to treat patients severely affected by RA, whose daily lives were blighted by the condition.

"TNF-blockers have been used in hundreds of thousands of patients in the last five to seven years in the US and UK.

"I think we all know that there are some risks with them.

"But as far as I can see the benefits far outweigh the risks for these patients who really have severe rheumatoid arthritis which is totally devastating and can be life-threatening," Dr Devey said.