Malignancies in the rheumatoid arthritis abatacept clinical development programme: an epidemiological assessment

Objective.Assess longterm tolerability, safety, and efficacy of subcutaneous (SC) abatacept (ABA) in methotrexate-refractory patients with rheumatoid arthritis (RA).Methods.The phase III, multinational Abatacept Comparison of Sub[QU]cutaneous Versus Intravenous in Inadequate Responders to MethotrexatE (ACQUIRE) trial comprised a 6-month, randomized, double-blind (DB) period, in which patients received intravenous (IV) or SC ABA, plus MTX, followed by an open-label, longterm extension (LTE), in which patients received SC ABA, 125 mg/week. Safety and efficacy from the LTE (∼3.5 yrs of exposure) are reported.Results.Patients who completed the DB period (1372/1385, 99.1%) entered the LTE; 1134 patients (82.7%) kept taking the treatment at time of reporting. Mean (SD) was 31.9 months (6.8); median (range) exposure was 33.0 (8–44) months. Patients entering the LTE had longstanding, moderate-to-severe disease [mean 7.6 (7.9) yrs and DAS28 (C-reactive protein) 6.2 (0.9)]. Incidence rates (events/100 patient-yrs) were reported for serious adverse events (8.76, 95% CI 7.71, 9.95), infections (44.80, 95% CI 41.76, 48.01), serious infections (1.72, 95% CI 1.30, 2.27), malignancies (1.19, 95% CI 0.86, 1.66), and autoimmune events (1.31, 95% CI 0.95, 1.79). Twenty-seven patients (2%) experienced injection-site reactions; all except 1 were mild. American College of Rheumatology 20, 50, and 70 responses achieved during the DB period were maintained through the LTE, and on Day 981 were 80.2% (95% CI 77.2, 83.2), 63.5% (95% CI 58.2, 68.9), and 39.5% (95% CI 34.0, 44.9) for patients who kept taking SC ABA, and 80.0% (95% CI 77.0, 83.0), 63.2% (95% CI 57.8, 68.7), and 39.2% (95% CI 33.7, 44.7) for those who switched from IV to SC ABA.Conclusion.These findings support SC ABA as a well-tolerated and efficacious longterm treatment for patients with RA and inadequate response to MTX (ClinicalTrials.gov identifier NCT00559585).

Section: Rheumatologysupporting

confidence: 52%

Section: Rheumatologysupporting

confidence: 52%

Subcutaneous Abatacept for the Treatment of Rheumatoid Arthritis: Longterm Data from the ACQUIRE Trial

Genovese

Pacheco‐Tena²,

Covarrubias³

et al. 2014

“…Compared with the general population, patients with RA have an elevated risk of developing malignancies, specifically lung cancer and lymphoma 15,16 . An analysis of clinical trial experience with abatacept, encompassing~8400 person-years of exposure, showed that the observed incidence rates of total malignancy, breast cancer, and lymphoma compared with the DB period remained unchanged and that overall incidence rates of cancer were consistent with expectation based on comparator RA cohorts treated with DMARD 17 .…”

Section: Discussionmentioning

confidence: 82%

Safety and Efficacy of the Selective Costimulation Modulator Abatacept in Patients with Rheumatoid Arthritis Receiving Background Methotrexate: A 5-year Extended Phase IIB Study

Westhovens

Kremer²,

Moreland³

et al. 2009

114

Objective.To evaluate the safety and efficacy of abatacept plus methotrexate (MTX) over 5 years in patients with rheumatoid arthritis.Methods.Patients were randomized to abatacept 10 or 2 mg/kg or placebo, plus MTX. Patients completing the 1-year, double-blind period entered the longterm extension, where all patients received a fixed dose of abatacept ~10 mg/kg. We describe safety analyses for all patients who received at least 1 dose of abatacept and efficacy analyses for the original ~10 mg/kg abatacept-treated group, over 5 years.Results.Of the 235 abatacept- or placebo-treated patients completing the double-blind period, 219 entered the longterm extension; 130 (59.4%) were continuing at Year 5. No unexpected safety events were observed during the longterm extension compared with the double-blind period. Incidence rates of adverse events (AE) and serious AE were 489.7 and 20.0/100 patient-years in Year 1 versus 374.9 and 18.9/100 patient-years in the cumulative period, respectively. Using exploratory analyses, improvements observed at Year 1 in the 10 mg/kg group were maintained at Year 5, as assessed by ACR responses (ACR20 = 77.1% vs 82.7%; ACR50 = 53.0% vs 65.4%; ACR70 = 28.9% vs 40.4% at Years 1 and 5, respectively) and disease activity (Low Disease Activity State = 48.2% vs 58.5%; Disease Activity Score-28-defined remission = 25.3% vs 45.3% at Years 1 and 5, respectively).Conclusion.Abatacept maintained the efficacy observed at Year 1 over 5 years of treatment, and demonstrated consistent safety and tolerability. These data, along with relatively high retention rates, support the longterm clinical benefit provided by selective T cell costimulation modulation. Clinical trial registry: ClinicalTrials.gov; clinical trial registration number: NCT00254293.

“…The contribution to the total exposure time for each patient ended at the first occurrence of the AE. SIR with 95% CI were calculated for hospitalized infections and malignancies for abatacept treatment versus comparator cohorts, adjusted for age and sex 23 . SIR (95% CI) were computed by dividing the observed numbers of events with abatacept in the cumulative treatment period by the expected numbers based on event rates in the comparator cohorts.…”

Section: Rheumatologymentioning

confidence: 99%

Safety of Abatacept Administered Intravenously in Treatment of Rheumatoid Arthritis: Integrated Analyses of up to 8 Years of Treatment from the Abatacept Clinical Trial Program

Weinblatt

Moreland²,

Westhovens³

et al. 2013

119

Objective.To assess the overall safety, including rare events, of intravenous (IV) abatacept treatment in rheumatoid arthritis (RA).Methods.Data from 8 clinical trials of IV abatacept in RA were pooled. Safety events were assessed during the short-term (duration ≤ 12 months) and cumulative (short-term plus longterm extensions) abatacept treatment periods. Incidence rates per 100 patient-years were calculated. Standardized incidence ratios (SIR) for hospitalized infections and malignancies were compared with external RA cohorts and, for malignancies, with the US general population.Results.There were 3173 IV abatacept-treated patients with 2331 patient-years of exposure in the short-term periods, and 4149 IV abatacept-treated patients with 12,132 patient-years of exposure in the cumulative period. Incidence rates for serious infections were low and consistent over time (3.68 for abatacept vs 2.60 for placebo during the short-term, and 2.87 for abatacept during the cumulative period). Hospitalized infections were generally similar to external RA patient cohorts and were consistent over time. Incidence rates of malignancies were similar for abatacept- and placebo-treated patients during the short-term period (0.73 vs 0.59) and remained low during the abatacept cumulative period (0.73). SIR of some tissue-specific malignancies (e.g., colorectal and breast) in the cumulative period tended to be lower, while others (lymphoma and lung) tended to be higher, compared with the general population; however, incidence rates were comparable with RA cohorts. Autoimmune events were rare and infusion reactions uncommon.Conclusion.Longterm safety of IV abatacept was consistent with the short-term, with no unexpected events and low incidence rates of serious infections, malignancies, and autoimmune events.