Durable Responses Seen for Abatacept in RA Patients

BOSTON – The safety and efficacy of abatacept were maintained throughout 5 years of treatment for patients with rheumatoid arthritis, with more than one-third of those who remained in the long-term extension phase of a multicenter trial achieving an ACR 70 response.

The initial double-blind trial enrolled 339 patients with rheumatoid arthritis (RA) who had had an inadequate response to methotrexate, randomizing them to receive 2 mg/kg abatacept, 10 mg/kg abatacept, or placebo for 1 year. They also received background methotrexate in doses of 10-30 mg/week, Dr. Rene R. Westhovens reported in a poster session at the annual meeting of the American College of Rheumatology.

Abatacept was given as a 30-minute infusion on days 1, 15, and 30, and every 30 days thereafter.

By week 52, 63% of patients receiving the higher dose of abatacept had achieved an ACR 20 response, compared with 36% of those receiving placebo. Moreover, 42% and 21% of those receiving 10 mg/kg of the active drug achieved ACR 50 and 70 responses, respectively, compared with 20% and 8% of those receiving placebo (Arthritis Rheum. 2005;52:2263-71).

Of the 235 patients who completed the double-blind phase of the trial, 219 entered the long-term open-label phase, during which all participants received the 10-mg/kg dose of abatacept plus methotrexate. Among these 219 patients, 84, 68, and 67 were from the original 10-mg/kg, 2-mg/kg, and placebo groups, respectively. Their mean age was 56 years, 74% were female, and their mean disease duration was 10 years. At 5 years, 130 (59%) remained on the drug, reported Dr. Westhovens of University Hospital Gasthuisberg Leuven (Belgium).

The improvements in ACR 20, ACR 50, and ACR 70 responses seen in the 10-mg/kg group in the blinded phase of the trial were maintained at year 5, with response rates of 83%, 65%, and 40%.

During the blinded phase, 55% of patients in the 10-mg/kg group had clinically meaningful improvements in physical function, defined as an increase of 0.3 units or more on the modified Health Assessment Questionnaire Disability Index. This was maintained by 53% at year 5.

The types and incidence of serious adverse events were similar in the double-blind and 5-year cumulative study periods, according to Dr. Westhovens. There were 20 serious adverse events per 100 patient-years reported among patients receiving the active treatment during the double-blind phase of the trial, and 19 serious adverse events per 100 patient-years during the open-label phase.

With almost 60% of patients still participating in the study at 5 years, responses remain durable, demonstrating that “abatacept provides long-term clinical benefits to patients with active RA,” Dr. Westhovens wrote.

He disclosed that he received consulting fees from Bristol-Myers Squibb Co., the sponsor of the study.

BOSTON – The safety and efficacy of abatacept were maintained throughout 5 years of treatment for patients with rheumatoid arthritis, with more than one-third of those who remained in the long-term extension phase of a multicenter trial achieving an ACR 70 response.

The initial double-blind trial enrolled 339 patients with rheumatoid arthritis (RA) who had had an inadequate response to methotrexate, randomizing them to receive 2 mg/kg abatacept, 10 mg/kg abatacept, or placebo for 1 year. They also received background methotrexate in doses of 10-30 mg/week, Dr. Rene R. Westhovens reported in a poster session at the annual meeting of the American College of Rheumatology.

Abatacept was given as a 30-minute infusion on days 1, 15, and 30, and every 30 days thereafter.

By week 52, 63% of patients receiving the higher dose of abatacept had achieved an ACR 20 response, compared with 36% of those receiving placebo. Moreover, 42% and 21% of those receiving 10 mg/kg of the active drug achieved ACR 50 and 70 responses, respectively, compared with 20% and 8% of those receiving placebo (Arthritis Rheum. 2005;52:2263-71).

Of the 235 patients who completed the double-blind phase of the trial, 219 entered the long-term open-label phase, during which all participants received the 10-mg/kg dose of abatacept plus methotrexate. Among these 219 patients, 84, 68, and 67 were from the original 10-mg/kg, 2-mg/kg, and placebo groups, respectively. Their mean age was 56 years, 74% were female, and their mean disease duration was 10 years. At 5 years, 130 (59%) remained on the drug, reported Dr. Westhovens of University Hospital Gasthuisberg Leuven (Belgium).

The improvements in ACR 20, ACR 50, and ACR 70 responses seen in the 10-mg/kg group in the blinded phase of the trial were maintained at year 5, with response rates of 83%, 65%, and 40%.

During the blinded phase, 55% of patients in the 10-mg/kg group had clinically meaningful improvements in physical function, defined as an increase of 0.3 units or more on the modified Health Assessment Questionnaire Disability Index. This was maintained by 53% at year 5.

The types and incidence of serious adverse events were similar in the double-blind and 5-year cumulative study periods, according to Dr. Westhovens. There were 20 serious adverse events per 100 patient-years reported among patients receiving the active treatment during the double-blind phase of the trial, and 19 serious adverse events per 100 patient-years during the open-label phase.

With almost 60% of patients still participating in the study at 5 years, responses remain durable, demonstrating that “abatacept provides long-term clinical benefits to patients with active RA,” Dr. Westhovens wrote.

He disclosed that he received consulting fees from Bristol-Myers Squibb Co., the sponsor of the study.

BOSTON – The safety and efficacy of abatacept were maintained throughout 5 years of treatment for patients with rheumatoid arthritis, with more than one-third of those who remained in the long-term extension phase of a multicenter trial achieving an ACR 70 response.

The initial double-blind trial enrolled 339 patients with rheumatoid arthritis (RA) who had had an inadequate response to methotrexate, randomizing them to receive 2 mg/kg abatacept, 10 mg/kg abatacept, or placebo for 1 year. They also received background methotrexate in doses of 10-30 mg/week, Dr. Rene R. Westhovens reported in a poster session at the annual meeting of the American College of Rheumatology.

Abatacept was given as a 30-minute infusion on days 1, 15, and 30, and every 30 days thereafter.

By week 52, 63% of patients receiving the higher dose of abatacept had achieved an ACR 20 response, compared with 36% of those receiving placebo. Moreover, 42% and 21% of those receiving 10 mg/kg of the active drug achieved ACR 50 and 70 responses, respectively, compared with 20% and 8% of those receiving placebo (Arthritis Rheum. 2005;52:2263-71).

Of the 235 patients who completed the double-blind phase of the trial, 219 entered the long-term open-label phase, during which all participants received the 10-mg/kg dose of abatacept plus methotrexate. Among these 219 patients, 84, 68, and 67 were from the original 10-mg/kg, 2-mg/kg, and placebo groups, respectively. Their mean age was 56 years, 74% were female, and their mean disease duration was 10 years. At 5 years, 130 (59%) remained on the drug, reported Dr. Westhovens of University Hospital Gasthuisberg Leuven (Belgium).

The improvements in ACR 20, ACR 50, and ACR 70 responses seen in the 10-mg/kg group in the blinded phase of the trial were maintained at year 5, with response rates of 83%, 65%, and 40%.

During the blinded phase, 55% of patients in the 10-mg/kg group had clinically meaningful improvements in physical function, defined as an increase of 0.3 units or more on the modified Health Assessment Questionnaire Disability Index. This was maintained by 53% at year 5.

The types and incidence of serious adverse events were similar in the double-blind and 5-year cumulative study periods, according to Dr. Westhovens. There were 20 serious adverse events per 100 patient-years reported among patients receiving the active treatment during the double-blind phase of the trial, and 19 serious adverse events per 100 patient-years during the open-label phase.

With almost 60% of patients still participating in the study at 5 years, responses remain durable, demonstrating that “abatacept provides long-term clinical benefits to patients with active RA,” Dr. Westhovens wrote.

He disclosed that he received consulting fees from Bristol-Myers Squibb Co., the sponsor of the study.