Survivin in adrenocortical tumors - pathophysiological implications and therapeutic potential

Treatment options for adrenocortical carcinoma (ACC) are very limited. In other solid tumors, small vaccination trials targeting the anti-apoptotic molecule survivin suggested immunological and clinical benefit in selected patients. Therefore, we investigated whether survivin might be a suitable target for immunotherapy in ACC. Survivin mRNA and protein expression was assessed in adrenal tissue specimens [by real-time-PCR in 29 ACC, 24 adrenocortical adenomas (ACA) and 12 normal adrenal glands; by immunohistochemistry in 167 ACCs, 15 ACA, and 5 normal adrenal glands]. Expression was correlated with clinical outcome using Kaplan-Meier and Cox regression analyses. The anti-apoptotic role of survivin was investigated in the SW13 ACC cell line using survivin siRNA. The presence of spontaneous survivin specific T-cells in peripheral blood was assessed by FACS dextramere staining in 29 ACC patients in comparison to healthy controls. Survivin mRNA in ACC was significantly overexpressed when compared with ACA or normal adrenal glands. Immunohistochemistry confirmed survivin protein expression in 97% of the ACCs. In 83% of samples, staining was moderate or high and clinical outcome in this subgroup showed a trend towards poorer prognosis [hazard ratio for death 2.28 (95% CI 0.99-5.28); p=0.053]. Survivin knockdown in SW-13 cell significantly increased the rate of apoptosis. Finally, spontaneous survivin-reactive T cells were detectable in 3 of 29 ACC patients. In conclusion, our data suggest that survivin could play an important role in the anti-apoptotic mechanisms in ACC and provide first hints that targeting survivin might be an interesting new therapeutic approach in this rare disease.

P-cadherin expression in Merkel cell carcinomas is associated with prolonged recurrence-free survival

BACKGROUND

 Merkel cell carcinoma (MCC) is a highly aggressive skin cancer, associated with advanced age, immunosuppression and Merkel cell polyomavirus (MCV) infections. As development and progression of cancer can be promoted by changes in cell adhesion proteins, we have previously analysed homo- and heterotypic cell-cell contacts of normal Merkel cells and MCCs and obtained indications for cadherin switching.

OBJECTIVES

To examine the prevalence and prognostic relevance of E-, N- and P-cadherin in MCCs.

METHODS

Paraffin-embedded MCC samples (n = 148) from 106 different patients were analysed by double-label immunostaining and immunofluorescence microscopy. MCV status was determined by real-time polymerase chain reaction. The cadherin repertoire and MCV status were correlated to clinical data, including tumour stage and recurrence-free survival.

RESULTS

Ninety-one per cent of all MCC were positive for N-cadherin whereas only 61·6% and 70·3% expressed E- and P-cadherin, respectively. P-cadherin was significantly more frequent in primary tumours than in lymph node metastases (81·9% vs. 40·9%, P = 0·0002). Patients with P-cadherin-positive primary tumours were in earlier tumour stages at initial diagnosis (P = 0·0046). Both in log-rank tests (P = 0·0474) and in multiple Cox regression analysis including age, sex, immunosuppression, stage at initial diagnosis and MCV status (hazard ratio 0·193, P = 0·0373), patients with P-cadherin-positive primary MCCs had significantly prolonged recurrence-free survival (mean 25·2 vs. 10·6 months; median 9·0 vs. 4·0 months). MCV DNA was detected in 78·2% of all MCC, more frequently in P-cadherin-positive MCC (P = 0·0008).

CONCLUSION

P-cadherin expression in MCCs predicts prolonged recurrence-free survival and may therefore indicate favourable prognosis.

Expression of the T-cell regulatory marker FOXP3 in primary cutaneous large B-cell lymphoma tumour cells

BACKGROUND

Primary cutaneous B-cell lymphomas (PCBCL) are subdivided into the aggressive form, primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL, LT) and two subtypes of indolent behaviour (primary cutaneous follicle centre lymphoma and primary cutaneous marginal zone B-cell lymphoma). The difference in clinical behaviour can be explained by the tumour cell itself, or the lymphoma microenvironment including the antitumour immune response.

OBJECTIVES

To investigate the presence of regulatory T cells (Treg), CD4+CD25+FOXP3+, in the microenvironment of PCBCL in correlation with clinical outcome.

METHODS

Tumour specimens of 55 consecutive cases of PCBCL were blinded and analysed for FOXP3, CD4 and CD25 expression by immunohistochemistry. Confocal images were taken with a Leica SP5. Statistical analyses were performed to determine significance. The test was considered significant when P<0.05.

RESULTS

The CD4 and FOXP3 expression as well as the CD4/FOXP3 ratio were significantly increased in PCBCL of indolent behaviour in contrast to PCLBCL, LT (P=0.0002 for CD4, P<0.0001 for FOXP3 and P=0.0345 for FOXP3/CD4 ratio). CD25 expression did not differ in the three groups (P=0.9414). Within the group of patients with PCLBCL, LT we identified a subgroup with FOXP3+ tumour cells as demonstrated by CD20/FOXP3 double stainings. Patients with FOXP3+ PCLBCL, LT tumour cells showed a better prognosis on Kaplan-Meier analysis.

CONCLUSION

High numbers of Treg in the lymphoma microenvironment correlate with a better prognosis in PCBCL. In PCLBCL, LT the presence of FOXP3+ tumour cells is beneficial for prognosis suggesting that FOXP3 expression of PCLBCL, LT tumour cells might serve as a tumour suppressor.

Merkel cell carcinoma--pathogenesis, clinical aspects and treatment

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin demonstrating a high rate of recurrence and metastasis. Indeed, 5-year rates for MCC specific survival are only about 60%. Although MCCs' incidence is rapidly increasing, it is still a very rare tumour. In this regard, the American Cancer Society had estimated for 2008 almost 1500 new cases in the USA. Recently, the newly identified Merkel cell polyomavirus has been found associated with most of the MCC cases. Nevertheless, the pathogenesis of MCC is not yet fully understood. Here, we will summarize recent findings of the pathogenesis of MCC, present an overview of clinical aspects and discuss treatment options for MCCs.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin. The incidence of this rare tumor is increasing rapidly; the American Cancer Society estimates for 2008 almost 1500 new cases in the USA. Thus, the incidence of MCC will exceed the incidence of cutaneous T-cell lymphoma. Moreover, the mortality rate of MCC at 33% is considerably higher than that of cutaneous melanoma. These clinical observations are especially disturbing as we are only recently beginning to understand the pathogenesis of MCC. For the same reason, the therapeutic approach is often unclear; reliable data are only available for the therapy of locoregional disease.

Sustained disease remission and inhibition of radiographic progression in methotrexate-naive patients with rheumatoid arthritis and poor prognostic factors treated with abatacept: 2-year outcomes

OBJECTIVE

To assess the efficacy and safety of abatacept plus methotrexate versus methotrexate alone in early erosive rheumatoid arthritis (RA).

METHODS

The AGREE was a 2-year phase IIIb multinational study in early (≤ 2 years) RA. During the double-blind period (year 1), patients were randomly assigned 1:1 to receive abatacept+methotrexate or methotrexate alone; all patients received open-label abatacept+methotrexate during year 2. Clinical outcomes assessed included 28-joint disease activity score (DAS28) defined remission, low disease activity score (LDAS), American College of Rheumatology (ACR) responses and physical function. Radiographic outcomes were assessed using the Genant-modified Sharp total score (TS). Safety was monitored throughout.

RESULTS

Of the 459 patients completing year 1, 433 patients (94.3%) completed year 2. DAS28-defined remission, LDAS, ACR and physical function were sustained through year 2 in the original abatacept+methotrexate group, with 55.2% in remission at 2 years. Upon introduction of abatacept in the methotrexate-alone group, additional patients achieved DAS28-defined remission (44.5% vs 26.9%), LDAS (60.4% vs 43.2%) and improved ACR 70 (49.8% vs 31.7%) for year 2 versus year 1. Less radiographic progression was observed at 2 years in the original abatacept+methotrexate group than the methotrexate-alone group (change in TS 0.84 vs 1.75, p<0.001). No new safety issues were seen. Similar rates of serious adverse events, serious infections and autoimmune events were observed in years 1 and 2.

CONCLUSIONS

The AGREE trial was the first to examine the impact of T-cell co-stimulation modulation with abatacept in patients with early erosive RA. Early treatment with abatacept+methotrexate resulted in greater sustainable clinical, functional and radiographic benefits than methotrexate alone, with acceptable safety and tolerability.

TRIAL REGISTRATION

NCT00122382.

Sorafenib and pegylated interferon-α2b in advanced metastatic melanoma: a multicenter phase II DeCOG trial

BACKGROUND

The combination of sorafenib, a multikinase inhibitor, and pegylated interferon-α2b (Peg-IFN-α2b) could potentially lead to an improved antitumoral response. Previously, combinations of interferon and sorafenib have been used in renal cell cancer.

PATIENTS AND METHODS

Patients with stage IV metastatic melanoma and no previous systemic therapies apart from adjuvant immunotherapy received Peg-IFN-α2b 3 μg/kg once per week, and sorafenib 400-mg b.i.d. for a minimum of 8 weeks. The primary study end point was disease control rate (DCR).

RESULTS

Between February 2008 and February 2009, 55 patients were enrolled with a median age of 64 years (20-85). At 8 weeks, 2 patients (3.6%) had a partial response (PR) and 14 patients a stable disease (25.5%), for a DCR of 29.1% in the intention-to-treat (ITT) population. The median progression-free survival in the ITT population was 2.47 months (95% confidence interval 1.22-3.72 months). The toxicity of sorafenib and Peg-IFN-α2b combination was characterized by mainly hematological side-effects, including one treatment-related bleeding complication with a fatal outcome. Other grade 3/4 toxic effects were fatigue and flu-like symptoms.

CONCLUSION

The combination of sorafenib and Peg-IFN-α2b showed modest clinical activity and some serious side-effects including fatal bleeding complications.

The efficacy and safety of abatacept in patients with non-life-threatening manifestations of systemic lupus erythematosus: results of a twelve-month, multicenter, exploratory, phase IIb, randomized, double-blind, placebo-controlled trial

OBJECTIVE

To evaluate abatacept therapy in patients with non-life-threatening systemic lupus erythematosus (SLE) and polyarthritis, discoid lesions, or pleuritis and/or pericarditis.

METHODS

In a 12-month, multicenter, exploratory, phase IIb randomized, double-blind, placebo-controlled trial, SLE patients with polyarthritis, discoid lesions, or pleuritis and/or pericarditis were randomized at a ratio of 2:1 to receive abatacept (∼10 mg/kg of body weight) or placebo. Prednisone (30 mg/day or equivalent) was given for 1 month, and then the dosage was tapered. The primary end point was the proportion of patients with new flare (adjudicated) according to a score of A/B on the British Isles Lupus Assessment Group (BILAG) index after the start of the steroid taper.

RESULTS

A total of 118 patients were randomized to receive abatacept and 57 to receive placebo. The baseline characteristics were similar in the 2 groups. The proportion of new BILAG A/B flares over 12 months was 79.7% (95% confidence interval [95% CI] 72.4, 86.9) in the abatacept group and 82.5% (95% CI 72.6, 92.3) in the placebo group (treatment difference -3.5 [95% CI -15.3, 8.3]). Other prespecified flare end points were not met. In post hoc analyses, the proportions of abatacept-treated and placebo-treated patients with a BILAG A flare were 40.7% (95% CI 31.8, 49.5) versus 54.4% (95% CI 41.5, 67.3), and the proportions with physician-assessed flare were 63.6% (95% CI 54.9, 72.2) and 82.5% (95% CI 72.6, 92.3), respectively; treatment differences were greatest in the polyarthritis group. Prespecified exploratory patient-reported outcomes (Short Form 36 health survey, sleep problems, fatigue) demonstrated a treatment effect with abatacept. The frequency of adverse events (AEs) was comparable in the abatacept and placebo groups (90.9% versus 91.5%), but serious AEs (SAEs) were higher in the abatacept group (19.8 versus 6.8%). Most SAEs were single, disease-related events occurring during the first 6 months of the study (including the steroid taper period).

CONCLUSION

Although the primary/secondary end points were not met in this study, improvements in certain exploratory measures suggest some abatacept efficacy in patients with non-life-threatening manifestations of SLE. The increased rate of SAEs requires further assessment.

Multi-organ failure in a previously healthy 10-year-old boy: streptococcal toxic shock syndrome (STSS) - a rare differential diagnosis

Streptococcal Toxic Shock Syndrome (STSS) is a severe toxin-mediated disease with acute onset. A previously healthy 10-year-old boy presented with abdominal pain, vomiting, diarrhoea and fever for 3 days. He was admitted with signs of an acute abdomen. A treatment with ibuprofen had been started before admission. The child developed a multi-organ failure with persistent hematuria, persistent fever, ascites, pericardial and pleural effusions. Intensive microbial and viral analysis did not result in any relevant finding. Detection by PCR of DNA of the streptococcal super-antigens speM and speL supported the diagnosis of STSS. After an intensive-care treatment of 4 weeks according to international critical-care guidelines the child could be discharged without residuals.

COX-2-dependent PGE(2) acts as a growth factor in mycosis fungoides (MF)

Cancer often originates from a site of persistent inflammation, and the mechanisms turning chronic inflammation into a driving force of carcinogenesis are intensely investigated. Cyclooxygenase-2 (COX-2) is an inducible key modulator of inflammation that carries out the rate-limiting step in prostaglandin synthesis. Aberrant COX-2 expression and prostaglandin E(2) (PGE(2)) production have been implicated in tumorigenesis. In this study we show that COX-2 is ectopically expressed in malignant T-cell lines from patients with cutaneous T-cell lymphoma (CTCL) as well as in situ in lymphocytic cells in 21 out of 22 patients suffering from mycosis fungoides (MF) in plaque or tumor stage. COX-2 is not expressed in lymphocytes of 11 patients with patch-stage MF, whereas sporadic COX-2 staining of stromal cells is observed in the majority of patients. COX-2 expression correlates with a constitutive production of PGE(2) in malignant T cells in vitro. These cells express prostaglandin receptors EP3 and EP4 and the receptor antagonist as well as small interfering RNA (siRNA) directed against COX-2, and specific COX-2 inhibitors strongly reduce their spontaneous proliferation. In conclusion, our data indicate that COX-2 mediated PGE(2) exerts an effect as a tumor growth factor in MF.

Impact of T-cell costimulation modulation in patients with undifferentiated inflammatory arthritis or very early rheumatoid arthritis: a clinical and imaging study of abatacept (the ADJUST trial)

Background

Several agents provide treatment for established rheumatoid arthritis (RA), but a crucial therapeutic goal is to delay/prevent progression of undifferentiated arthritis (UA) or very early RA.

Objective

To determine the impact of T-cell costimulation modulation in patients with UA or very early RA.

Methods

In this double-blind, phase II, placebocontrolled, 2-year study, anti-cyclic citrullinated peptide (CCP)2-positive patients with UA (not fulfilling the ACR criteria for RA) and clinical synovitis of two or more joints were randomised to abatacept (∼10 mg/kg) or placebo for 6 months; the study drug was then terminated. The primary end point was development of RA (by ACR criteria) at year 1. Patients were monitored by radiography, MRI, CCP2, rheumatoid factor and 28 joint count Disease Activity Score (DAS28) over 2 years.

Results

At year 1, 12/26 (46%) abatacept-treated versus 16/24 (67%) placebo-treated patients developed RA (difference (95% CI) −20.5% (−47.4% to 7.8%)). Adjusted mean changes from baseline to year 1 in Genant-modified Sharp radiographic scores for abatacepttreated versus placebo-treated patients, respectively, were 0 versus 1.1 for total score, and 0 versus 0.9 for erosion score. Mean changes from baseline to year 1 in MRI erosion, osteitis and synovitis scores were 0, 0.2 and 0.2, respectively, versus 5.0, 6.7 and 2.3 in the abatacept versus placebo groups. Safety was comparable between groups; serious adverse events occurred in one patient (3.6%) in each group.

Conclusion

Abatacept delayed progression of UA/very early RA in some patients. An impact on radiographic and MRI inhibition was seen, which was maintained for 6 months after treatment stopped. This suggests that it is possible to alter the progression of RA by modulating T-cell responses at a very early stage of disease.

Trial registration number

NCT00124449.

Stem cells, melanoma and cancer stem cells: the good, the bad and the evil?

Most cancers contain morphologically heterogeneous populations of cells. While this observation may partly be explained by the coexistence of multiple genetic sub-clones arising through independent somatic mutations and/or as a result of differentiation processes in the tumor microenvironment, it also implies that the tumor may be formed from undifferentiated ''stem cell-like'' cells called ''cancer stem cells'' or ''cancer-initiating cells''. These cells are thought to constitute one or several rare subpopulations in a given tumor and would be strongly responsible for initiation of tumor development and growth as well as for metastasis and recurrence after cytoreductive therapy. However, while the concept of cancer stem cells has been first established for human myeloid leukemia in the 1960s, it has only much later been extended to other solid tumors such as breast or brain cancers and most recently to melanoma. Thus, it is presently unclear which role a sufficiently characterized population of melanoma stem cells plays in cancer promotion and progression. Here, we review the emerging melanoma stem cell model and discuss the biological and therapeutic implications of the model.

Clinical efficacy and safety of abatacept in methotrexate-naive patients with early rheumatoid arthritis and poor prognostic factors

Objectives:

To assess the efficacy and safety of abatacept in methotrexate-naive patients with early rheumatoid arthritis (RA) and poor prognostic factors.

Methods:

In this double-blind, phase IIIb study, patients with RA for 2 years or less were randomly assigned 1 : 1 to receive abatacept (∼10 mg/kg) plus methotrexate, or placebo plus methotrexate. Patients were methotrexate-naive and seropositive for rheumatoid factor (RF), anti-cyclic citrullinated protein (CCP) type 2 or both and had radiographic evidence of joint erosions. The co-primary endpoints were the proportion of patients achieving disease activity score in 28 joints (DAS28)-defined remission (C-reactive protein) and joint damage progression (Genant-modified Sharp total score; TS) at year 1. Safety was monitored throughout.

Results:

At baseline, patients had a mean DAS28 of 6.3, a mean TS of 7.1 and mean disease duration of 6.5 months; 96.5% and 89.0% of patients were RF or anti-CCP2 seropositive, respectively. At year 1, a significantly greater proportion of abatacept plus methotrexate-treated patients achieved remission (41.4% vs 23.3%; p<0.001) and there was significantly less radiographic progression (mean change in TS 0.63 vs 1.06; p = 0.040) versus methotrexate alone. Over 1 year, the frequency of adverse events (84.8% vs 83.4%), serious adverse events (7.8% vs 7.9%), serious infections (2.0% vs 2.0%), autoimmune disorders (2.3% vs 2.0%) and malignancies (0.4% vs 0%) was comparable for abatacept plus methotrexate versus methotrexate alone.

Conclusions:

In a methotrexate-naive population with early RA and poor prognostic factors, the combination of abatacept and methotrexate provided significantly better clinical and radiographic efficacy compared with methotrexate alone and had a comparable, favourable safety profile.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin. More than one-third of MCC patients will die from this cancer, making it twice as lethal as malignant melanoma. Despite the fact that MCC is still a very rare tumor, its incidence is rapidly increasing; the American Cancer Society estimates for 2008 almost 1,500 new cases in the USA. These clinical observations are especially disturbing as the pathogenesis of MCC is not yet fully understood; however, a number of recent reports contribute to a better understanding of its pathogenesis. Here we describe findings regarding the role of Wnt, MAPK and Akt signaling as well as possible aberrations in the p14ARF/p53/RB tumor suppressor network in MCC. Most important, and possibly with high impact on future therapeutic approaches is the demonstration that a polyomavirus has frequently integrated in the genome of the MCC cells prior to tumor development.

[Spectroscopic imaging of the human liver using 3D CSI: optimization and application in patients with metastatic uvea melanoma]

PURPOSE

(31)P MR spectroscopy (MRS) allows the noninvasive assessment of metabolic alterations in tumors. Due to physical as well as technical limitations, mostly large and single voxels are used. We used a spatially resolved (31)P MRS technique to characterize metabolic abnormalities inside and adjacent to liver metastases of patients with uvea melanoma.

MATERIALS AND METHODS

Optimization of 3D chemical shift imaging (3D CSI) was performed in healthy volunteers (n = 19; voxel size 25 ml). Patients (n = 8) with liver metastases were then examined. Cross sectional imaging was available for all patients.

RESULTS

Compared to healthy volunteers, the PME/PDE ratios of patients with liver metastasis were significantly higher (0.56 +/- 0.30 vs. 0.39 +/- 0.21; p < 0.05). A trend towards increased PME/beta ATP ratios (2.07 +/- 1.83 vs. 1.02 +/- 0.45; p = 0.12) and decreased Pi/PME ratios (0.57 +/- 0.29 vs. 1.06 +/- 0.58; p = 0.06) was also observed. Patients with metastases > or = 5 cm showed significantly higher PME/PDE ratios (0.68 +/- 0.17 vs. 0.45 +/- 0.03; p < 0.05). Liver parenchyma adjacent to metastases did not show any significant changes compared to non-diseased tissue.

CONCLUSION

3D CSI allows the simultaneous analysis of metabolic alterations in diseased as well as in healthy human liver. Metastases show significant metabolic alterations. Thus, (31)P MRS opens new possibilities for therapeutic monitoring.

Validation of the 28-joint Disease Activity Score (DAS28) and European League Against Rheumatism response criteria based on C-reactive protein against disease progression in patients with rheumatoid arthritis, and comparison with the DAS28 based on erythrocyte sedimentation rate

Objective:

To validate and compare the definition of the Disease Activity Score 28 based on C-reactive protein (DAS28 (CRP)) to the definition based on erythrocyte sedimentation rate (ESR).

Methods:

Data were analysed from two randomised, double-blind, placebo-controlled trials of abatacept of 6-month and 12-month duration in patients with rheumatoid arthritis. European League Against Rheumatism (EULAR) response criteria and the proportion of patients in remission (DAS28 <2.6) based on the two DAS28 definitions were examined. Trends in radiographic progression (erosion score, joint space narrowing score and total score) and physical function (Health Assessment Questionnaire Disability Index (HAQ-DI)) across the EULAR responder states (none, moderate and good) were analysed.

Results:

There was general agreement in determining the EULAR responder state using both DAS28 definitions (κ = 0.80, 95% CI 0.76 to 0.83). Overall, there was 82.4% agreement on the EULAR response criteria; when disagreements occurred, the DAS28 (CRP) yielded a better EULAR response more often then DAS28 (ESR) (12.6% vs 4.9%, respectively). There was also agreement in determining remission: κ = 0.69 (95% CI 0.60 to 0.78). Radiographic progression decreased in patients treated with abatacept across EULAR states (from none to moderate to good) based on both definitions. For patients treated with placebo, the trend was not as pronounced, with radiographic scores higher for moderate vs non-responders. For physical function, similar trends were observed across the EULAR states for both DAS28 definitions.

Conclusions:

The DAS28 (CRP) has been validated against radiographic progression and physical function. While the DAS28 (CRP) yielded a better EULAR response more often than the DAS28 (ESR), the validation profile was similar to the DAS28 (ESR), indicating that both measures are useful for assessing disease activity in patients with rheumatoid arthritis.

Abatacept inhibits progression of structural damage in rheumatoid arthritis: results from the long-term extension of the AIM trial

OBJECTIVE

Assess the effect of abatacept on progression of structural damage over 2 years in patients with rheumatoid arthritis who had an inadequate response to methotrexate.

METHODS

539 patients entered an open-label extension of the AIM (Abatacept in Inadequate responders to Methotrexate) trial and received abatacept. Radiographic assessment of the hands and feet was performed at baseline, year 1 and year 2. At year 2, each patient's radiographs were scored for progression blinded to sequence and treatment allocation.

RESULTS

In patients treated with abatacept for 2 years, greater reduction in progression of structural damage was observed in year 2 than in year 1. The mean change in total Genant-modified Sharp scores was reduced from 1.07 units in year 1 to 0.46 units in year 2. Similar reductions were observed in erosion and joint space narrowing scores. Following 2 years of treatment with abatacept, 50% of patients had no progression of structural damage as defined by a change in the total score of < or =0 compared with baseline. 56% of patients treated with abatacept had no progression during the first year compared with 45% of patients treated with placebo. In their second year of treatment with abatacept, more patients had no progression than in the first year (66% vs 56%).

CONCLUSIONS

Abatacept has a sustained effect that inhibits progression of structural damage. Furthermore, the mean change in radiographic progression in patients treated with abatacept for 2 years was significantly lower in year 2 versus year 1, suggesting that abatacept may have an increasing disease-modifying effect on structural damage over time.

Efficacy and safety of abatacept or infliximab vs placebo in ATTEST: a phase III, multi-centre, randomised, double-blind, placebo-controlled study in patients with rheumatoid arthritis and an inadequate response to methotrexate

OBJECTIVES

This double-blind trial evaluated the efficacy and safety of abatacept or infliximab vs placebo. The primary objective of this study was to evaluate the mean change from baseline in Disease Activity Score (based on erythrocyte sedimentation rates; DAS28 (ESR)) for the abatacept vs placebo groups at day 197.

METHODS

Patients with rheumatoid arthritis (RA) and an inadequate response to methotrexate (MTX) were randomised 3:3:2 to abatacept ( approximately 10 mg/kg every 4 weeks, n = 156), infliximab (3 mg/kg every 8 weeks, n = 165), or placebo (every 4 weeks, n = 110) and background MTX. Safety and efficacy were assessed throughout the study.

RESULTS

Similar patient demographics and clinical characteristics were present at baseline between groups, with mean scores of approximately 1.7 for HAQ-DI and 6.8 for DAS28 (ESR). At 6 months, mean changes in DAS28 (ESR) were significantly greater for abatacept vs placebo (-2.53 vs -1.48, p<0.001) and infliximab vs placebo (-2.25 vs -1.48, p<0.001). For abatacept vs infliximab treatment at day 365, reductions in the DAS28 (ESR) were -2.88 vs -2.25. At day 365, the following response rates were observed for abatacept and infliximab, respectively: American College of Rheumatology (ACR) 20, 72.4 and 55.8%; ACR 50, 45.5 and 36.4%; ACR 70, 26.3 and 20.6%; low disease activity score (LDAS), 35.3 and 22.4%; DAS28-defined remission, 18.7 and 12.2%; good European League Against Rheumatism (EULAR) responses, 32.0 and 18.5%; and Health Assessment Questionnaire Disability Index (HAQ-DI), 57.7 and 52.7%. Mean changes in physical component summary (PCS) were 9.5 and 7.6, and mental component summary (MCS) were 6.0 and 4.0, for abatacept and infliximab, respectively. Over 1 year, adverse events (AEs) (89.1 vs 93.3%), serious AEs (SAEs) (9.6 vs 18.2%), serious infections (1.9 vs 8.5%) and discontinuations due to AEs (3.2 vs 7.3%) and SAEs (2.6 vs 3.6%) were lower with abatacept than infliximab.

CONCLUSIONS

In this study, abatacept and infliximab (3 mg/kg every 8 weeks) demonstrated similar efficacy. Overall, abatacept had a relatively more acceptable safety and tolerability profile, with fewer SAEs, serious infections, acute infusional events and discontinuations due to AEs than the infliximab group.

TRIAL REGISTRATION NUMBER

NCT00095147.