Under the Skin: Two Rx's to Treat RA

Rheumatoid arthritis drugs Orencia and Humira were similarly effective

(RxWiki News) When it comes to rheumatoid arthritis, there is no one Rx that works best for all patients. A Rx that does wonders for one patient may do little for another. As such, Rx comparisons may be needed.

In a recent study, researchers compared two rheumatoid arthritis medications: Orencia (abatacept) and Humira (adalimumab). Both medications appeared to improve arthritis symptoms and to slow the progression of the disease.

The safety of the medication was also similar, other than the fact that Humira-treated patients had more injection site reactions.

"Ask about your Rx options for RA."

The study - which was conducted by Michael E. Weinblatt, MD, of Brigham and Women's Hospital, and colleagues - included 646 patients who were treated with either Orencia or Humira. A total of 86.2 percent of patients in the Orencia group and 82 percent of patients in the Humira group completed 12 months of treatment.

Both Humira and Orencia come in subcutaneous form, meaning they are injected just under the skin. 

After one year, 64.8 percent of Orencia-treated patients and 63.4 percent of Humira-treated patients showed an American College of Rheumatology 20 percent improvement response (ACR20).

ACR20 is a score that indicates an arthritis patient has had 20 percent improvement in the number of tender or swollen joints and 20 percent improvement in three of five other criteria.

Results also showed similar rates of radiographic non-progression (disease progression as shown by x-ray) between the two groups. Progression of rheumatoid arthritis was slowed or stopped in 84.8 percent of Orencia-treated patients and 88.6 percent of Humira-treated patients.

The rate of negative side effects was 10.1 percent among patients in the Orencia group and 9.1 percent among those in the Humira group. The rate of serious infection was 2.2 percent among Orencia-treated patients and 2.7 percent among Humira-treated patients.

Patients quit taking Orencia 3.5 percent of the time due to negative side effects and 1.3 percent of the time due to serious negative side effects. Patients quit taking Humira 6.1 percent of the time due to negative side effects and 3 percent of the time due to serious negative side effects.

Injection site reactions happened in 3.8 percent of patients taking Orencia and 9.1 percent of the time in patients taking Humira.

According to the authors, these results showed that Orencia and Humira were similarly effective in patients with rheumatoid arthritis.

"The safety was generally similar, other than the occurrence of significantly more local injection site reactions in patients treated with [Humira]," they concluded.

The study was published December 27 in Arthritis & Rheumatism. The research was funded by Bristol-Myers Squibb, the developer of Orencia. Multiple authors reported potential conflicts of interest with various pharmaceutical companies, including Bristol-Myers Squibb, Pfizer and Abbott, the manufacturer of Humira.

Review Date: 
January 9, 2013