The 2010 Scientific Sessions of the American College of Rheumatology, or ACR, was held from November 7 to 11 in Atlanta. The features below highlight just some of the studies that emerged from the meeting.

» Promising Results for Experimental RA Drug
» Comparing Therapies for ANCA-Positive Vasculitis
» Abatacept Well-Tolerated in Patients With RA

Promising Results for Experimental RA Drug

The Particulars: Tasocitinib is an investigational oral JAK inhibitor that may be beneficial for patients suffering from rheumatoid arthritis (RA). It is thought to block cytokine production. A phase III trial involving 611 patients with RA was conducted to assess the effect of tasocitinib on reducing symptoms, disability, and remission.

Data Breakdown: In the study, responses at the ACR20 symptom level after 3 months were seen in 65.7% of patients receiving tasocitinib at 10 mg twice daily and in 59.8% of those taking a 5 mg dose, compared with 26.7% of those taking placebo. ACR50 and ACR70 symptom responses were seen in 36.8% and 20.3%, respectively, of the 10-mg tasocitinib patients at 3 months, compared with 12.5% and 5.8% of the placebo group. Similar results were seen in responses assessed with the Health Assessment Questionnaire-Disability Index. An analysis of remission (according to the Disease Activity Scale-28) at 3 months found that tasocitinib did not offer a significant advantage at either dosage relative to placebo. However, remission was seen in 6.0% of the 5-mg group (relative to placebo).

Take Home Pearl: Tasocitinib appears to offer some benefits for RA patients, but more studies are needed to assess efficacy and safety.

Comparing Therapies for ANCA-Positive Vasculitis [back to top]

The Particulars: Standard treatment for patients with Wegener’s granulomatosis and microscopic polyangiitis—the vasculitides characterized by the presence of antineutrophil cytoplasmic antibodies (ANCA)—consists of remission induction with cyclophosphamide and steroids, and then maintenance therapy with azathioprine or methotrexate. However, relapses are common, and toxicity is problematic.

Data Breakdown: In a randomized study, 156 patients were assigned to one of two treatment groups. One received 2,000 mg/day mycophenolate mofetil initially, which was then gradually reduced and stopped at 42 months. The other group received an initial dose of 2 mg/kg/day azathioprine, which also was reduced and withdrawn at 42 months. Overall, 55.0% of patients undergoing maintenance therapy with mycophenolate mofetil relapsed during a median of 39 months follow-up, compared with 37.5% of those receiving azathioprine. There were no differences between the groups’ Vasculitis Damage Index scores, glomerular filtration rates, proteinuria, or adverse events.

Take Home Pearl: Azathioprine appears to be more effective than mycophenolate mofetil in preventing relapse in patients with ANCA-positive vasculitis.

Abatacept Well-Tolerated in Patients With RA [back to top]

The Particulars: Abatacept is a fusion protein composed of a modified Fc portion of human immunoglobulin G1 fused to the extracellular domain of human cytotoxic T-lymphocyte-associated antigen 4. It is currently approved for treating moderate-to-severe rheumatoid arthritis (RA) and juvenile idiopathic arthritis in patients aged 6 and older.

Data Breakdown: Researchers conducted an integrated analysis of more than 12,000 patient-years of safety data, which involved more than 4,000 patients, to evaluate the long-term safety of abatacept and to detect rare events. Data from 8 clinical trials of abatacept were classified into short-term and long-term periods. Exposure to abatacept over 7 years was not associated with an increased incidence of serious adverse events. The most common adverse events were infections requiring hospitalization, and few opportunistic infections were observed. The safety profile of abatacept was stable as exposure duration increased.

Take Home Pearl: Abatacept appears to be safe and generally well tolerated in patients with RA for the long term.