Subcutaneous abatacept versus intravenous abatacept: a phase IIIb noninferiority study in patients with an inadequate response to methotrexate

Population Pharmacokinetics and Exposure-Response of Subcutaneous Atezolizumab in Patients With Non-Small Cell Lung Cancer

IMscin001 is a two-part dose-finding (Phase Ib) and -confirmation (Phase III) study to evaluate atezolizumab pharmacokinetics of subcutaneous (SC) compared with intravenous (IV) administration in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC). The objectives of the current analyses were to characterize the population pharmacokinetics (popPK) of atezolizumab and to determine the relationship between atezolizumab exposure and safety and efficacy endpoints in IMscin001. A previously validated IV popPK model was extended to add SC absorption parameters using SC and IV data from Phase Ib and Phase III of IMscin001 (N = 435), and covariate effects were investigated on the SC absorption parameters. The exposure-response (ER) investigation was performed using SC data following 1875 mg every three weeks (q3w) administration in the Phase III portion of IMscin001 (N = 246). The clinical endpoints were objective response rate, progression-free survival, or overall survival for efficacy, serious adverse events, special interest adverse events, Grades 3-5 adverse events, infusion-related reaction, or injection site reactions for safety. Atezolizumab SC absorption was characterized by a first-order absorption with a bioavailability of 71.8% and an absorption rate constant of 0.304 day-1. The extended popPK model was adequate to predict atezolizumab PK after IV and SC administrations and to predict individual exposure metrics. For all efficacy and safety endpoints, atezolizumab exposure was not statistically significant (p-value > 0.05) in the ER models. The non-inferior popPK exposure and flat ER results supported atezolizumab SC dose at 1875 mg q3w.

Real-world clinical outcomes and rationale for initiating abatacept as a first-line biologic for patients with anticitrullinated protein antibody- and rheumatoid factor-positive rheumatoid arthritis

Aim: In rheumatoid arthritis (RA), seropositivity for both anticitrullinated protein antibody (ACPA) and rheumatoid factor (RF) is associated with disease severity and therapeutic response. Biologic (b) disease-modifying antirheumatic drugs (DMARDs) such as abatacept are recommended after inadequate response or contraindication to conventional synthetic DMARDs. This retrospective cohort study aimed to describe changes in Clinical Disease Activity Index (CDAI) measures over 12 months among patients with ACPA+ and RF+ RA with an inadequate response to methotrexate treated with abatacept as a first-line bDMARD. Patients & methods: Patient data were abstracted from medical records by treating rheumatologists. Analyses included McNemar tests for paired proportions or paired t-tests to assess longitudinal changes in CDAI scores, and Kaplan-Meier methods for time-to-event outcomes. Serious AEs and rationale for initiating treatment were recorded. Results: Overall, 296 patients were included. Mean CDAI scores improved (decreased) by 34.0, 61.0 and 74.0% (all p < 0.001) from baseline to 3-6 months, 6-12 months and ≥12 months after abatacept initiation, respectively. Of 279 patients not in CDAI low disease activity (LDA) or remission at baseline, 24.7% of patients achieved it within 6 months, 56.3% within 12 months and 71.0% at any point during follow-up after abatacept initiation. Median time to CDAI LDA/remission was 10.2 months. Serious AEs were reported in 2.4% of patients. Common reasons reported by rheumatologists for initiating abatacept were effectiveness/efficacy (52.7%), safety (31.4%) and patient preference (25.3%). Conclusion: In this analysis of patients with ACPA+ and RF+ RA treated with abatacept as a first-line bDMARD in a clinical practice setting, clinical outcomes and remission rates were improved at all time points, providing real-world evidence to further support the use of abatacept in this patient population.

Predicting Human Subcutaneous Bioavailability of Therapeutic Monoclonal Antibodies from Systemic Clearance and Volume of Distribution

Subcutaneous delivery of monoclonal antibody therapeutics is often preferred to intravenous delivery due to better patient compliance and overall lower cost to the healthcare system. However, the systemic absorption of biologics dosed subcutaneously is often incomplete. The aim of this work was to describe a human bioavailability prediction method for monoclonal antibodies delivered subcutaneously that utilizes intravenous pharmacokinetic parameters as input. A two-compartment pharmacokinetic model featuring a parallel-competitive absorption pathway and a presystemic metabolism pathway was employed. A training data set comprised 19 monoclonal antibodies (geometric mean bioavailability of 68%), with previously reported human pharmacokinetic parameters, while a validation set included data compiled from 5 commercial drug products (geometric mean bioavailability of 69%). A single fitted absorption rate constant, paired with compound-specific estimates of presystemic metabolism rate proportional to compound-specific systemic clearance parameters, resulted in calculations of human subcutaneous bioavailability closely mimicking clinical data in the training data set with a root-mean-square error of 5.5%. Application of the same approach to the validation data set resulted in predictions characterized by 12.6% root-mean-square error. Factors that may have impacted the prediction accuracy include a limited number of validation data set compounds and an uncertainty in the absorption rate, which were subsequently discussed. The predictive method described herein provides an initial estimate of the subcutaneous bioavailability based exclusively on pharmacokinetic parameters available from intravenous dosing.

Subcutaneous vs intravenous abatacept in rheumatoid arthritis-interstitial lung disease. National multicentre study of 397 patients

BACKGROUND

Evidence on abatacept (ABA) utility for rheumatoid arthritis (RA) - associated interstitial lung disease (ILD) is growing. Clinical trials have shown equivalence in subcutaneous (SC) and intravenous (IV) administration of ABA for articular manifestations. However, this has not been studied in respiratory outcomes.

OBJECTIVE

To compare the effectiveness of ABA in RA-ILD patients according to the route of administration.

METHODS

National retrospective multicentre study of RA-ILD patients on treatment with ABA. They were divided into 2 groups: a) IV, and b) SC. The following outcomes were analysed from baseline to final follow-up using linear mixed models: a) forced vital capacity (FVC), b) diffusing capacity of the lungs for carbon monoxide (DLCO), c) chest high resolution computed tomography (HRCT), d) dyspnoea, e) RA activity, and f) sparing corticosteroids effect.

RESULTS

A total of 397 patients were included (94 IV-ABA and 303 SC-ABA), median follow-up of 24 [10-48] months. After adjustment for possible confounders, FVC and DLCO remained stable during the first 24 months without differences between IV-ABA and SC-ABA (p = 0.6304 and 0.5337). Improvement/ stability of lung lesions in HRCT was observed in 67 % of patients (75 % IV-ABA, 64 % SC-ABA; p = 0.07). Dyspnoea stabilized/ improved in 84 % of patients (90 % IV-ABA, 82 % SC-ABA; p = 0.09). RA - disease activity improved in both groups. No statistically significant differences regarding any of the variables studied between the two groups were found. ABA was withdrawn in 87 patients (21.9 %), 45 % IV-ABA and 37 % SC-ABA (p = 0.29). ILD worsening and articular inefficacy were the most common reasons for ABA discontinuation.

CONCLUSION

In patients with RA-ILD, ABA seems to be equally effective regardless of the route of administration.

Abatacept retention and clinical effectiveness in patients with rheumatoid arthritis in a real-world setting in Taiwan

AIM

To evaluate real-world abatacept retention and clinical outcomes in patients with rheumatoid arthritis in Taiwan.

METHODS

This prospective, observational study enrolled patients with rheumatoid arthritis aged ≥20 years who received abatacept in real-world practice. The primary endpoint was the abatacept retention rate at 24 months. Patients were categorized into subgroups based on abatacept treatment status and previous biological disease-modifying antirheumatic drug (bDMARD) therapy. Risk factors affecting abatacept retention were determined by regression analysis.

RESULTS

A total of 212 patients were enrolled. The overall abatacept retention rate at 24 months among all patients was 59.9% (95% confidence interval 53.0%-66.6%). Patients who were ongoing users of abatacept and bDMARD-naïve had the highest retention rate (76.3%); of these, 31.6% achieved low disease activity or remission after 2 years. Previous treatment with bDMARDs was associated with an increased risk of abatacept discontinuation (hazard ratio 1.99; p = .002). The most common reasons for abatacept discontinuation were drug switch (11.3%) and loss to follow-up (6.1%). Abatacept was well-tolerated with no new safety signals.

CONCLUSION

The 24-month retention rate of abatacept was 59.9%; abatacept was associated with improved clinical outcomes and was well-tolerated in the real-world setting in Taiwan.

Non-TNF biologics and their biosimilars in rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic inflammatory rheumatic disease that affects both the articular and extra-articular structures, leading to significant joint damage, disability and excess mortality. The treatment algorithm of RA has changed tremendously in the past 1-2 decades because of the emergence of novel biological therapies that target different mechanisms of action in addition to TNFα.

AREAS COVERED

This article summarizes the evidence and safety of the non-TNF biological DMARDs in the treatment of RA, including those that target B cells, T-cell co-stimulation, interleukin (IL)-6 and granulocyte-monocyte colony-stimulating factor (GM-CSF). The targeted synthetic DMARDs such as the Janus kinase inhibitors are not included. The availability of the less costly biosimilars has enabled more patients to receive biological therapy earlier in the course of the disease. The evidence for the non-TNF biosimilar compounds in RA is also reviewed.

EXPERT OPINION

There are unmet needs of developing novel therapeutic agents to enhance the response rate and provide more options for difficult-to-treat RA. These include the newer generation biologic and targeted synthetic DMARDs. A personalized treatment strategy in RA requires evaluation of the cellular, cytokine, genomic and transcriptomic profile that would predict treatment response to biologic or targeted DMARDs of different mechanisms of action.

Retention rate of abatacept in rheumatoid arthritis patients in a real-life setting: results from a monocentric cohort

OBJECTIVE

Data from trials demonstrated that abatacept (ABA) has a good safety and efficacy profile in treating rheumatoid arthritis. We have studied the retention rate of ABA in a real-life cohort of patients with rheumatoid arthritis.

METHODS

This is a monocentric, retrospective study including patients with rheumatoid arthritis classified by the American College of Rheumatology/European League Against Rheumatism 2010 criteria who started treatment with ABA. The Kaplan-Meier method was applied to evaluate the ABA retention rate.

RESULTS

This analysis was conducted on 161 patients [male/female 21/140, median age 65 years, interquartile range (IQR) 18.7, median disease duration 169 months, IQR 144.0]. 111 patients (68.9%) received ABA subcutaneously. ABA was associated with methotrexate in 61.9% of patients and was the first biological disease-modifying antirheumatic drug in 41%. We observed a median ABA survival of 66 months [95% confidence interval (CI) 57.3-74.7], with a retention rate of 88% at 6 months and 50.9% at 5 years. Drug survival was significantly higher in patients treated with ABA subcutaneously and in male patients (p=0.039 and p=0.018, respectively). Adjusted for main confounders, female gender was the main predictor of withdrawal (hazard ratio 5.1, 95% CI 1.2-21.3).

CONCLUSIONS

Our study shows that better survival is associated with subcutaneous administration and male gender, confirming ABA effectiveness.

Anti-Drug Antibody Incidence Comparison of Therapeutic Proteins Administered Via Subcutaneous vs. Intravenous Route

Subcutaneous (SC) administration of therapeutic proteins is perceived to pose higher risk of immunogenicity when compared with intravenous (IV) route of administration (RoA). However, systematic evaluations of clinical data to support this claim are lacking. This meta-analysis was conducted to compare the immunogenicity of the same therapeutic protein by IV and SC RoA. Anti-drug antibody (ADA) data and controlling variables for 7 therapeutic proteins administered by both IV and SC routes across 48 treatment groups were analyzed. RoA was the primary independent variable of interest while therapeutic protein, patient population, adjusted dose, and number of ADA samples were controlling variables. Analysis of variance was used to compare the ADA incidence between IV and SC RoA, while accounting for controlling variables and potential interactions. Subsequently, 10 additional therapeutic proteins with ADA data published for both IV and SC administration were added to the above 7 therapeutic proteins and were evaluated for ADA incidence. RoA had no statistically significant effect on ADA incidence for the initial dataset of 7 therapeutic proteins (p = 0.55). The only variable with a significant effect on ADA incidence was the therapeutic protein. None of the other controlling variables, including their interactions with RoA, was significant. When all data from the 17 therapeutic proteins were pooled, there was no statistically significant effect of RoA on ADA incidence (p = 0.81). In conclusion, there is no significant difference in ADA incidence between the IV and SC RoA, based on analysis of clinical ADA data from 17 therapeutic proteins.

Towards the Lowest Efficacious Dose: Results From a Multicenter Noninferiority Randomized Open-Label Controlled Trial Assessing Tocilizumab or Abatacept Injection Spacing in Rheumatoid Arthritis in Remission

OBJECTIVE

We assess the clinical and structural impact at two years of progressively spacing tocilizumab (TCZ) or abatacept (ABA) injections versus maintenance at full dose in patients with rheumatoid arthritis in sustained remission.

METHODS

This multicenter open-label noninferiority (NI) randomized clinical trial included patients with established rheumatoid arthritis in sustained remission receiving ABA or TCZ at a stable dose. Patients were randomized to treatment maintenance (M) at full dose (M-arm) or progressive injection spacing (S) driven by the Disease Activity Score in 28 joints every 3 months up to biologics discontinuation (S-arm). The primary end point was the evolution of disease activity according to the Disease Activity Score in 44 joints during the 2-year follow-up analyzed per protocol with a linear mixed-effects model, evaluated by an NI test based on the one-sided 95% confidence interval (95% CI) of the slope difference (NI margin 0.25). Other end points were flare incidence and structural damage progression.

RESULTS

Overall, 202 of the 233 patients included were considered for per protocol analysis (90 in S-arm and 112 in M-arm). At the end of follow-up, 16.2% of the patients in the S-arm could discontinue their biologic disease-modifying antirheumatic drug, 46.9% tapered the dose and 36.9% returned to a full dose. NI was not demonstrated for the primary outcome, with a slope difference of 0.10 (95% CI 0.10-0.31) between the two arms. NI was not demonstrated for flare incidence (difference 42.6%, 95% CI 30.0-55.1) or rate of structural damage progression at two years (difference 13.9%, 95% CI -6.7 to 34.4).

CONCLUSION

The Towards the Lowest Efficacious Dose trial failed to demonstrate NI for the proposed ABA or TCZ tapering strategy.

Clinical Pharmacology Approaches to Support Approval of New Routes of Administration for Therapeutic Proteins

Intravenous or subcutaneous routes of administration (ROAs) are common dosing routes for therapeutic proteins. Eleven therapeutic proteins with approval for one ROA have subsequently received approval for a second ROA. The clinical programs supporting the second ROA consistently leveraged data from the first ROA and included studies that characterized the pharmacokinetics (PKs) of the drug administered by the new ROA to identify an appropriate dosage regimen. The selected dosing regimen was then further evaluated in clinical trials designed with various primary end points. All programs implemented model-informed drug development approaches to ensure that the selected regimens would achieve comparable systemic exposures (PK-based bridging) or pharmacodynamic (PD) responses (PD-based bridging) as the reference ROA. To support the approval of a second ROA, these programs either demonstrated noninferiority in PK, PD, and/or clinical end points for the second ROA, or established efficacy and safety through a comparison to a placebo treatment. The accumulative examples showed that clinical trials which provided the primary evidence to support approvals of the second ROA generally demonstrated noninferiority in the systemic exposures regardless of being specified as an end point or not in the study protocols. The experience to date supports the use of PK- and PD-based bridging approaches not only in the selection of dosing regimens for a second ROA to be tested in clinical studies, but also for providing evidence of effectiveness to support approval, when appropriate.

Subcutaneous Administration of Monoclonal Antibodies: Pharmacology, Delivery, Immunogenicity, and Learnings From Applications to Clinical Development

Subcutaneous (s.c.) administration of monoclonal antibodies (mAbs) can reduce treatment burden for patients and healthcare systems compared with intravenous (i.v.) infusion through shorter administration times, made possible by convenient, patient-centric devices. A deeper understanding of clinical pharmacology principles related to efficacy and safety of s.c.-administered mAbs over the past decade has streamlined s.c. product development. This review presents learnings from key constituents of the s.c. mAb development pathway, including pharmacology, administration variables, immunogenicity, and delivery devices. Restricted mAb transportation through the hypodermis explains their incomplete absorption at a relatively slow rate (pharmacokinetic (PK)) and may impact mAb-cellular interactions and/or onset and magnitude of physiological responses (pharmacodynamic). Injection volumes, formulation, rate and site of injection, and needle attributes may affect PKs and the occurrence/severity of adverse events like injection-site reactions or pain, with important consequences for treatment adherence. A review of immunogenicity data for numerous compounds reveals that incidence of anti-drug antibodies (ADAs) is generally comparable across i.v. and s.c. routes, and complementary factors including response magnitude (ADA titer), persistence over time, and neutralizing antibody presence are needed to assess clinical impact. Finally, four case studies showcase how s.c. biologics have been clinically developed: (i) by implementation of i.v./s.c. bridging strategies to streamline PD-1/PD-L1 inhibitor development, (ii) through co-development with i.v. presentations for anti-severe acute respiratory syndrome-coronavirus 2 antibodies to support rapid deployment of both formulations, (iii) as the lead route for bispecific T cell engagers (BTCEs) to mitigate BTCE-mediated cytokine release syndrome, and (iv) for pediatric patients in the case of dupilumab.

Advancing Subcutaneous Dosing Regimens for Biotherapeutics: Clinical Strategies for Expedited Market Access

In recent years, subcutaneous administration of biotherapeutics has made significant progress. The self-administration market for rheumatoid arthritis has witnessed the introduction of additional follow-on biologics, while the first subcutaneous dosing options for monoclonal antibodies have become available for multiple sclerosis. Oncology has also seen advancements with the authorization of high-volume subcutaneous formulations, facilitated by the development of high-concentration formulations and innovative delivery systems. Regulatory and Health Technology Assessment bodies increasingly consider preference data in filing dossiers, particularly in evaluating novel drug delivery methods. The adoption of a pharmacokinetic-based clinical bridging approach has become standard for transitioning from intravenous to subcutaneous administration. Non-inferiority studies with pharmacokinetics as the only primary endpoint have started deviating from traditional randomization schemes, favoring the subcutaneous route and comparing with historical intravenous data. While nonclinical and computational models made progress in predicting safety and immunogenicity for subcutaneously dosed antibodies, clinical trial evidence remains essential due to inter-individual variations and the impact of formulation parameters on anti-drug antibody formation. Ongoing technological advancements and the expanding knowledge base on pharmacokinetic-pharmacodynamic correlation across specialty areas are expected to further accelerate clinical development of subcutaneous biologics.

Subcutaneous abatacept for the treatment of rheumatoid arthritis in routine clinical practice in Germany, Austria, and Switzerland: 2-year retention and efficacy by treatment line and serostatus

INTRODUCTION/OBJECTIVES

The ASCORE study on treatment for rheumatoid arthritis (RA) showed better retention and clinical response rates for abatacept as first-line versus later-line therapy. This post hoc analysis of ASCORE assessed 2-year retention, efficacy, and safety of subcutaneous (SC) abatacept in Germany, Austria, and Switzerland.

METHODS

Adults with RA who initiated SC abatacept 125 mg once weekly were assessed. Primary endpoint was abatacept retention rate at 2 years. Secondary endpoints: proportions of patients with low disease activity (LDA)/remission per Disease Activity Score in 28 joints based on erythrocyte sedimentation rate (≤ 3.2), Simplified Disease Activity Index (≤ 11), and Clinical Disease Activity Index (≤ 10). Outcomes were analyzed by treatment line and serostatus.

RESULTS

For the pooled cohort, the 2-year abatacept retention rate was 47.6%; retention was highest in biologic-naïve patients (50.5% [95% confidence interval 44.9, 55.9]). Patients seropositive for both anti-citrullinated protein antibody (ACPA) and rheumatoid factor (RF; + / +) at baseline had a higher 2-year abatacept retention rate than patients with single seropositivity for either APCA or RF or double-seronegativity (- / -), irrespective of treatment line. At 2 years, a higher proportion of patients who were biologic-naïve were in LDA/remission than patients with one or ≥ two prior biologics.

CONCLUSION

A higher proportion of patients with + / + RA (compared with - / - RA) had abatacept retention after 2 years. Early identification of patients with seropositive RA may facilitate a precision-medicine approach to RA treatment, leading to a higher proportion of patients in LDA/remission.

TRIAL REGISTRATION NUMBER

NCT02090556; date registered: March 18, 2014 (retrospectively registered). Key Points • This post hoc analysis of a German-speaking subset of European patients with RA from the global ASCORE study (NCT02090556) showed that retention of SC abatacept within this subset was 47.6%, with good clinical outcomes after 2 years. • Patients with double-seropositive RA (ACPA and RF positive) had higher retention of abatacept than patients with double-seronegative RA (ACPA and RF negative). Retention and clinical responses were highest for patients who were biologic-naïve compared with patients who had one or ≥ two prior biologic treatments. • These real-world data may be useful for clinicians in informing individualized treatment pathways for patients with RA, and fostering superior disease control and clinical outcomes.

Conversion From Intravenous In-Hospital Belatacept Injection to Subcutaneous Abatacept Injection in Kidney Transplant Recipients During the First COVID-19 Stay-at-Home Order in France

The first COVID-19 stay-at-home order came into effect in France on 17 March 2020. Immunocompromised patients were asked to isolate themselves, and outpatient clinic visits were dramatically reduced. In order to avoid visits to the hospital by belatacept-treated kidney transplant recipients (KTRs) during the initial period of the pandemic, we promptly converted 176 KTRs at two French transplant centers from once-monthly 5 mg/kg in-hospital belatacept infusion to once-weekly 125 mg subcutaneous abatacept injection. At the end of follow-up (3 months), 171 (97.16%) KTRs survived with a functioning graft, 2 (1.14%) had died, and 3 (1.70%) had experienced graft loss. Two patients (1.1%) experienced acute T cell-mediated rejection. Nineteen patients (10.80%) discontinued abatacept; 47% of the KTRs found the use of abatacept less restrictive than belatacept, and 38% would have preferred to continue abatacept. Mean eGFR remained stable compared to baseline. Seven patients (3.9%) had COVID-19; among these, two developed severe symptoms but survived. Only one patient had a de novo DSA. Side effects of abatacept injection were uncommon and non-severe. Our study reports for the first time in a large cohort that once-weekly injection of abatacept appears to be feasible and safe in KTRs previously treated with belatacept.

Anti-Drug Antibodies in the Biological Therapy of Autoimmune Rheumatic Diseases

Autoimmune rheumatic diseases are a cluster of heterogeneous disorders that share some clinical symptoms such as pain, tissue damage, immune deregulation, and the presence of inflammatory mediators. Biologic disease-modifying antirheumatic drugs are some of the most effective treatments for rheumatic diseases. However, their molecular and pharmacological complexity makes them potentially immunogenic and capable of inducing the development of anti-drug antibodies. TNF inhibitors appear to be the main contributors to immunogenicity because they are widely used, especially in rheumatoid arthritis. Immunogenicity response on these treatments is crucial since the appearance of ADAs has consequences in terms of safety and efficacy. Therefore, this review proposes an overview of the immunogenicity of biological agents used in autoimmune rheumatic diseases highlighting the prevalence of anti-drug antibodies.

Sustained Remission and Outcomes with Abatacept plus Methotrexate Following Stepwise Dose De-escalation in Patients with Early Rheumatoid Arthritis

INTRODUCTION

One target of rheumatoid arthritis (RA) treatment is to achieve early sustained remission; over the long term, patients in sustained remission have less structural joint damage and physical disability. We evaluated Simplified Disease Activity Index (SDAI) remission with abatacept + methotrexate versus abatacept placebo + methotrexate and impact of de-escalation (DE) in anti-citrullinated protein antibody (ACPA)-positive patients with early RA.

METHODS

The phase IIIb, randomized, AVERT-2 two-stage study (NCT02504268) evaluated weekly abatacept + methotrexate versus abatacept placebo + methotrexate.

PRIMARY ENDPOINT

SDAI remission (≤ 3.3) at week 24. Pre-planned exploratory endpoint: maintenance of remission in patients with sustained remission (weeks 40 and 52) who, from week 56 for 48 weeks (DE period), (1) continued combination abatacept + methotrexate, (2) tapered abatacept to every other week (EOW) + methotrexate for 24 weeks with subsequent abatacept withdrawal (abatacept placebo + methotrexate), or (3) withdrew methotrexate (abatacept monotherapy).

RESULTS

Primary study endpoint was not met: 21.3% (48/225) of patients in the combination and 16.0% (24/150) in the abatacept placebo + methotrexate arm achieved SDAI remission at week 24 (p = 0.2359). There were numerical differences favoring combination therapy in clinical assessments, patient-reported outcomes (PROs) and week 52 radiographic non-progression. After week 56, 147 patients in sustained remission with abatacept + methotrexate were randomized (combination, n = 50; DE/withdrawal, n = 50; abatacept monotherapy, n = 47) and entered DE. At DE week 48, SDAI remission (74%) and PRO improvements were mostly maintained with continued combination therapy; lower remission rates were observed with abatacept placebo + methotrexate (48.0%) and with abatacept monotherapy (57.4%). Before withdrawal, de-escalating to abatacept EOW + methotrexate preserved remission.

CONCLUSIONS

The stringent primary endpoint was not met. However, in patients achieving sustained SDAI remission, numerically more maintained remission with continued abatacept + methotrexate versus abatacept monotherapy or withdrawal.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02504268. Video abstract (MP4 62241 KB).

A narrative review on subcutaneous injection components used for alopecia

BACKGROUND

Studies reporting the development and effectiveness of topical agents for alopecia are available. However, it was difficult to demonstrate a direct advantage of subcutaneous injection rather than topical application. Since existing articles lack information, future studies are needed to solve these problems and to narrow the knowledge gap.

AIMS

Present article is aimed to review of the possible materials used in subcutaneous injection for alopecia with a hope for better guiding the analytic application and further evaluating the effective component for alopecia management.

METHODS

A wide range of clinical articles was retrieved using electronic databases to determine the possible components used in subcutaneous injection and their potential mechanism of action.

RESULTS

Eight components from 19 articles were found to be used for alopecia via subcutaneous administration.

CONCLUSIONS

The current study illuminated the curative effects of possible substances and discussed the efficacy of subcutaneous injections.

Points to consider for cost-effective use of biological and targeted synthetic DMARDs in inflammatory rheumatic diseases: results from an umbrella review and international Delphi study

OBJECTIVES

To develop evidence-based points to consider for cost-effective use of biological and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in the treatment of inflammatory rheumatic diseases, specifically rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis.

METHODS

Following EULAR procedures, an international task force was formed, consisting of 13 experts in rheumatology, epidemiology and pharmacology from seven European countries. Twelve strategies for cost-effective use of b/tsDMARDs were identified through individual and group discussion. For each strategy, PubMed and Embase were systematically searched for relevant English-language systematic reviews and, for six strategies, additionally for randomised controlled trials (RCTs). Thirty systematic reviews and 21 RCTs were included. Based on the evidence, a set of overarching principles and points to consider was formulated by the task force using a Delphi procedure. Level of evidence (1a-5) and grade (A-D) were determined for each point to consider. Individual voting on the level of agreement (LoA; between 0 (completely disagree) and 10 (completely agree)) was performed anonymously.

RESULTS

The task force agreed on five overarching principles. For 10 of 12 strategies, the evidence was sufficient to formulate one or more points to consider, leading to 20 in total, regarding response prediction, drug formulary use, biosimilars, loading doses, low-dose initial therapy, concomitant conventional synthetic DMARD use, route of administration, medication adherence, disease activity-guided dose optimisation and non-medical drug switching. Ten points to consider (50%) were supported by level 1 or 2 evidence. The mean LoA (SD) varied between 7.9 (1.2) and 9.8 (0.4).

CONCLUSION

These points to consider can be used in rheumatology practices and complement inflammatory rheumatic disease treatment guidelines to incorporate cost-effectiveness in b/tsDMARD treatment.

Monoclonal antibody and protein therapeutic formulations for subcutaneous delivery: high-concentration, low-volume vs. low-concentration, high-volume

Biologic drugs are used to treat a variety of cancers and chronic diseases. While most of these treatments are administered intravenously by trained healthcare professionals, a noticeable trend has emerged favoring subcutaneous (SC) administration. SC administration of biologics poses several challenges. Biologic drugs often require higher doses for optimal efficacy, surpassing the low volume capacity of traditional SC delivery methods like autoinjectors. Consequently, high concentrations of active ingredients are needed, creating time-consuming formulation obstacles. Alternatives to traditional SC delivery systems are therefore needed to support higher-volume biologic formulations and to reduce development time and other risks associated with high-concentration biologic formulations. Here, we outline key considerations for SC biologic drug formulations and delivery and explore a paradigm shift: the flexibility afforded by low-to-moderate-concentration drugs in high-volume formulations as an alternative to the traditionally difficult approach of high-concentration, low-volume SC formulation delivery.

Development of Therapeutic Proteins for a New Subcutaneous Route of Administration after the Establishment of Intravenous Dosages: A Systematic Review

Therapeutic proteins may first be developed as intravenous (i.v.) therapies with new subcutaneous (s.c.) dosage forms being subsequently developed to provide an alternative route of administration. As of August 2022, there have been 9 therapeutic proteins which were developed as a new s.c. dosage form after the approval of the corresponding i.v. product. This article provides a systematic review of prior experiences in the i.v. to s.c. switch development programs. We describe what types of clinical studies were conducted to support the i.v. to s.c. switch for these nine therapeutic proteins. Publicly available scientific advice from health authorities is summarized, particularly regarding recommendations on overall development strategy, dose selection, immunogenicity assessment, and indication extrapolation. The clinical data from these i.v. to s.c. development programs demonstrate that: (1) when switching from i.v. dosing to s.c. dosing, trough drug concentration (C_trough ) from s.c. dosing should not be inferior to i.v. dosing with average drug concentration (C_avg ; equivalent to AUC, area under the curve after correcting for dosing intervals between i.v. and s.c. administration) being matched or non-inferior to i.v. dosing; and (2) with appropriate s.c. dose regimens, treatment with s.c. therapeutic proteins can generally achieve similar efficacy and safety as the corresponding i.v. products, suggesting that the much higher maximum concentration (C_max ) after i.v. infusion as compared with that from s.c. injection is often not relevant to the treatment effect.

Assessing Immunogenicity of Biologic Drugs in Inflammatory Joint Diseases: Progress Towards Personalized Medicine

Biologic drugs have greatly improved treatment outcomes of inflammatory joint diseases, but a substantial proportion of patients either do not respond to treatment or lose response over time. Drug immunogenicity, manifested as the formation of anti-drug antibodies (ADAb), constitute a significant clinical problem. Anti-drug antibodies influence the pharmacokinetics of the drug, are associated with reduced clinical efficacy, and an increased risk of adverse events such as infusion reactions. The prevalence of ADAb differs among drugs and diseases, and the detection of ADAb also depends on the assay format. Most data exist for the tumor necrosis factor-alpha inhibitors infliximab and adalimumab, with a frequency of ADAb that ranges from 10 to 60% across studies. Measurement of ADAb and serum drug concentrations, therapeutic drug monitoring, has been suggested as a strategy to optimize therapy with biologic drugs. Although the recent randomized clinical Norwegian Drug Monitoring (NOR-DRUM) trials show promise towards a personalized medicine prescribing approach by therapeutic drug monitoring, several challenges remain. A plethora of assay formats, with widely differing properties, is currently used for measuring ADAb. Comparing results between different assays and laboratories is difficult, which complicates the development of cut-offs necessary for guidelines and the implementation of ADAb measurements in clinical practice. With the possible exception of infliximab, limited data on clinical relevance and cost effectiveness exist to support therapeutic drug monitoring as a routine clinical strategy to monitor biologic drugs in inflammatory joint diseases. The aim of this review is to provide an overview of the characteristics and prevalence of ADAb, predisposing factors to ADAb formation, commonly used assessment methods, clinical consequences of ADAb, and the potential implications of ADAb assessments for everyday treatment of inflammatory joint diseases.

Real-world effectiveness and safety of tofacitinib and abatacept in patients with rheumatoid arthritis

OBJECTIVE

We compared the 52-week effectiveness and safety of tofacitinib (TOF) and abatacept (ABT) in patients with RA in a real-world setting and investigated a role of human leucocyte antigens (HLA)-DRB1 shared epitope (SE) in the effectiveness.

METHODS

RA patients starting TOF (n = 187) and ABT (n = 183) were enrolled. Effectiveness was compared after reducing the selection bias to a minimum using the inverse probability of treatment weighting (IPTW) based on propensity scores. The influence of SE alleles on effectiveness was compared within each treatment group. A treatment group comparison was also performed within SE-positive and SE-negative groups.

RESULTS

Herpes zoster and some laboratory abnormalities were more frequent in the TOF group than in the ABT group. Patient characteristics did not differ significantly between treatment groups after adjustments with IPTW. The TOF group had a significantly higher proportion of DAS in 28 joints using ESR (DAS28-ESR) remission at week 52 than the ABT group. The DAS28-ESR at week 12 and thereafter was not affected by the copy number of SE alleles in the TOF group, but decreased significantly as the copy number increased in the ABT group. In SE-positive patients, remission and drug retention rates did not differ significantly between the two treatment groups. In SE-negative patients, the TOF group showed significantly higher remission and drug retention rates than the ABT group.

CONCLUSION

The present results suggest that TOF is more effective with regard to remission at week 52 based on treatment responses in SE-negative RA patients.

Retention of subcutaneous abatacept for the treatment of rheumatoid arthritis: real-world results from the ASCORE study: an international 2-year observational study

OBJECTIVES

To evaluate retention, efficacy, and safety of subcutaneous (SC) abatacept over 2 years in patients with moderate-to-severe RA in the Abatacept SubCutaneOus in Routine clinical practicE (ASCORE) study.

METHODS

Patients with RA who initiated SC abatacept 125 mg once weekly were enrolled in the international, observational, prospective multicentre ASCORE study into biologic-naïve or ≥ 1 prior biologic failure cohorts.

PRIMARY ENDPOINT

abatacept retention rate at 2 years. Secondary endpoints: proportion of patients with good/moderate EULAR response rates based on DAS28 (ESR), low disease activity and/or remission according to DAS28 (ESR; ≤ 3.2/ < 2.6), SDAI (≤ 11/ ≤ 3.3), CDAI (≤ 10/ ≤ 2.8), and Boolean criteria. Retention rate by baseline serostatus was evaluated post hoc.

RESULTS

Overall, 47% of patients remained on abatacept for 2 years, irrespective of treatment line. Higher abatacept retention rates were associated with lower prior biologic exposure. Generally, clinical outcomes showed that the proportion of patients with low disease activity/remission was higher in biologic-naïve patients (vs biologic-failure) and similar in those with 1 and ≥ 2 prior biologic failures. In patients on treatment at 2 years, good/moderate EULAR response rates of ~ 80% were consistently noted irrespective of prior biologic exposure. Across treatment lines, retention was greater in patients with seropositive (vs seronegative) RA. Patients with rheumatoid factor/anti-citrullinated protein antibody single-positive RA who were bio-naïve had higher retention than patients who were bio-experienced.

CONCLUSIONS

In the ASCORE study, SC abatacept retention was 47% at 2 years with good clinical outcomes and was well-tolerated in the real-world setting. Abatacept retention and clinical response rates were higher in patients who received abatacept as an earlier- versus later-line biologic drug treatment and in those with seropositive RA.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02090556.

Pegylation Reduces the Uptake of Certolizumab Pegol by Dendritic Cells and Epitope Presentation to T-Cells

Pegylation of biopharmaceuticals is the most common strategy to increase their half-life in the blood and is associated with a reduced immunogenicity. As antigen presentation is a primary event in the activation of CD4 T-cells and initiation of Anti-Drug Antibody (ADA) response, we investigated the role of the PEG molecule on the T-cell reactivity of certolizumab pegol (CZP), a pegylated anti-TNFα Fab. We generated T-cell lines raised against CZP and its non-pegylated form (CZNP) and demonstrated CZP primed few T-cells in comparison to CZNP. CZP-primed lines from 3 donors responded to a total of 5 epitopes, while CZNP-primed lines from 3 donors responded to a total of 7 epitopes, 4 epitopes were recognized by both CZP- and CZNP-primed lines. In line with this difference of T-cell reactivity, CZP is less internalized by the dendritic cells than CZNP. In vitro digestion assay of CZP by Cathepsin B showed a rapid removal of the PEG moiety, suggesting a limited influence of PEG on CZP proteolysis. We therefore demonstrate that pegylation diminishes antigen capture by dendritic cells, peptide presentation to T-cells and T-cell priming. This mechanism might reduce immunogenicity and contribute to the long half-life of CZP and possibly of other pegylated molecules.

Toward Overcoming Treatment Failure in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by inflammation and bone erosion. The exact mechanism of RA is still unknown, but various immune cytokines, signaling pathways and effector cells are involved. Disease-modifying antirheumatic drugs (DMARDs) are commonly used in RA treatment and classified into different categories. Nevertheless, RA treatment is based on a "trial-and-error" approach, and a substantial proportion of patients show failed therapy for each DMARD. Over the past decades, great efforts have been made to overcome treatment failure, including identification of biomarkers, exploration of the reasons for loss of efficacy, development of sequential or combinational DMARDs strategies and approval of new DMARDs. Here, we summarize these efforts, which would provide valuable insights for accurate RA clinical medication. While gratifying, researchers realize that these efforts are still far from enough to recommend specific DMARDs for individual patients. Precision medicine is an emerging medical model that proposes a highly individualized and tailored approach for disease management. In this review, we also discuss the potential of precision medicine for overcoming RA treatment failure, with the introduction of various cutting-edge technologies and big data.

Analysis of the Immunogenicity from Abatacept-Treated Pediatric Patients With Polyarticular-Course Juvenile Idiopathic Arthritis: Findings From Two Phase III Clinical Trials

Objective

The goal of this article is to present the analysis of anti‐abatacept antibody data from children with polyarticular‐course juvenile idiopathic arthritis (pJIA), treated with abatacept. The data are from 395 participants with pJIA from two abatacept registrational trials.

Methods

We analyzed immunogenicity data according to age groups, administration route (intravenous [IV] or subcutaneous [SC]), drug treatment interruption, and co‐medications (with or without methotrexate [MTX]) to assess impact on the incidence of anti‐abatacept antibodies.

Results

The overall immunogenicity incidences observed in both JIA trials ranged between 4.7% and 23.3%. There was a slightly higher immunogenicity incidence in the 2–5‐year‐old participants (15.2%) compared with 6–17‐year‐old participants (4.7%). In the study with SC dosing, the overall incidence on treatment was 2.3% (3% if co‐dosed with MTX), similar to the incidence for Period A of the IV study (similar duration of treatment as the SC study), which was 2.1% (1.4% if co‐dosed with MTX). In the IV study, the period following a 6‐month interruption in treatment had comparable immunogenicity incidences (22.9% with interruption vs. 18.2% without interruption, both co‐dosed with MTX and 0% for both not co‐dosed with MTX). In most cases, participants co‐dosed with MTX had higher immunogenicity incidences than those on abatacept alone.

Conclusion

Although some trends were noted in terms of incidence according to age and MTX co‐dosing, none where conclusive owing to differences in population size. Drug holiday had no impact on immunogenicity incidence once treatment was resumed, and incidences across SC and IV dosing were comparable. There was no impact of immunogenicity on pharmacokinetics, safety, and efficacy.

Impact of the HLA-DRB1 shared epitope on responses to treatment with tofacitinib or abatacept in patients with rheumatoid arthritis

Objectives

The aim of this study was to compare the clinical effectiveness of tofacitinib and abatacept and clarify the impact of the HLA-DRB1 shared epitope (SE) on responses to these treatments in patients with rheumatoid arthritis (RA).

Methods

After adjustments by propensity score matching, 70 out of 161 patients receiving tofacitinib and 70 out of 131 receiving abatacept were extracted. The clinical effectiveness of both drugs over 24 weeks and the impact of the copy numbers of SE on effectiveness outcomes were investigated.

Results

The percentage of patients in remission in the 28-joint count disease activity score using the erythrocyte sedimentation rate (DAS28-ESR) did not significantly differ between patients receiving tofacitinib and abatacept at week 24 (32% vs 37%, p = 0.359). The mean change at week 4 in DAS28-ESR from baseline was significantly greater in patients receiving tofacitinib than in those receiving abatacept (− 1.516 vs − 0.827, p = 0.0003). The percentage of patients in remission at week 4 was 30% with tofacitinib and 15% with abatacept (p = 0.016). When patients were stratified by the copy numbers of SE alleles, differences in these numbers did not affect DAS28-ESR scores of patients receiving tofacitinib. However, among patients receiving abatacept, DAS28-ESR scores were significantly lower in patients carrying 2 copies of SE alleles than in those carrying 0 copies at each time point throughout the 24-week period. Furthermore, the percentage of patients in remission with DAS28-ESR at week 24 was not affected by the copy numbers of SE alleles in patients receiving tofacitinib (p = 0.947), whereas it significantly increased as the copy numbers became higher in patients receiving abatacept (p = 0.00309). Multivariable logistic regression analyses showed a correlation between the presence of SE and DAS28-ESR remission in patients receiving abatacept (OR = 25.881, 95% CI = 3.140–213.351, p = 0.0025), but not in those receiving tofacitinib (OR = 1.473, 95% CI = 0.291–7.446, p = 0.639).

Conclusions

Although the clinical effectiveness of tofacitinib and abatacept was similar at week 24, tofacitinib was superior to abatacept for changes from baseline in DAS28-ESR and the achievement of remission at week 4. SE positivity was associated with the achievement of DAS28-ESR remission by week 24 in patients receiving abatacept, but not in those receiving tofacitinib.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02612-w.

Costo per responder di upadacitinib e abatacept nel trattamento dell’artrite reumatoide da moderata a grave in Italia

Purpose:

The objective of this economic evaluation was to compare the cost per responder between upadacitinib and abatacept (intravenous [iv] or subcutaneous [sc]) in patients with moderate-to-severe Rheumatoid Arthritis (RA) in Italy.

Methods:

The clinical efficacy was assessed based on SELECT-CHOICE study results. The clinical efficacy of upadacitinib and abatacept (iv or sc) was measured by Clinical Remission (CR), Low Disease Activity (LDA) and American College of Rheumatology response (ACR20, 50 and 70). The treatment cost was based on the number of administrations dispensed at 12 or 24 weeks. The cost per responder was adopted as a cost-effectiveness indicator.

Results:

Independent of the clinical efficacy measure used and the duration of treatment considered, the cost per responder was consistently lower for upadacitinib compared to abatacept (iv or sc) across all clinical measures. For example, considering the CR at 24 weeks, the cost per responder for upadacitinib was € 9,417 compared to € 17,817 for abatacept sc or to € 23,110 for abatacept iv. The differences in the cost per responder between upadacitinib and abatacept (iv or sc) increased when higher ACR response levels were considered.

Conclusions:

These results suggested that upadacitinib is a cost-effectiveness option compared to abatacept (iv or sc) from the perspective of the Italian National Health Service in patients with moderate-to-severe Rheumatoid Arthritis in Italy.

Current and Emerging DMARDs for the Treatment of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is the most prevalent form of inflammatory arthritis. It is a profoundly serious and severe disease that if it goes untreated could have severe consequences to the joints and health of the patient who carries this diagnosis. The treatment of RA has dramatically changed since the year 2000, with the discovery of the TNFis, then other biologics, and finally the JAKi. All these new medications with or without methotrexate in combination, tight control and treat to target have produced a revolution in the outcome of this disease. We reviewed and summarized the treatment options, and the most significant papers for each one of these new drugs. The reader could have a full picture with all the references of the recent publications. We also updated the biosimilar situation in RA, as well as the new drugs that will be coming to the market in the next 5 years.

Model-Based Selection and Recommendation for Subcutaneous Abatacept Dose in Patients With Polyarticular Juvenile Idiopathic Arthritis

The selective T-cell costimulation modulator abatacept is approved for treatment of adult rheumatoid arthritis (RA) and polyarticular juvenile idiopathic arthritis (pJIA; 6-17 years [intravenous] and 2-17 years [subcutaneous]). An extrapolation approach was taken to determine subcutaneous weight-tiered doses of abatacept to evaluate in patients with pJIA. Population pharmacokinetic (PPK) and exposure-response (E-R) analyses were conducted to determine whether the weight-tiered subcutaneous regimen provides near-maximal efficacy and is therapeutically comparable to the intravenous regimen in patients with pJIA aged 2-17 years. Combined study data from intravenous or subcutaneous abatacept were used to assess clinically relevant exposure outcomes. The PPK model was developed with data from 13 phase 2/3 studies in RA and pJIA; the E-R model for the American College of Rheumatology pediatric scores (JIA-ACR 30/50/70/100 responses) in month 4 was developed with data from 2 phase 3 pJIA studies. Predefined covariates were investigated in both analyses. PPK model-predicted exposures were steady-state peak, trough (Cminss ), and time-averaged concentrations. Abatacept PK was characterized by a linear 2-compartment model (zero-order intravenous infusion, first-order subcutaneous absorption, first-order elimination); body weight was the only clinically relevant covariate. Cminss was the best exposure predictor for the JIA-ACR response: log odds for response increased in proportion to log-transformed Cminss ; JIA-ACR30 approached a plateau when Cminss ≥ 10 μg/mL. The PPK and E-R analyses demonstrated that the weight-tiered subcutaneous and intravenous abatacept dosing regimens provide near-maximal efficacy and are clinically comparable across children with pJIA who are > 2 years old.

Efficacy and safety of abatacept in active primary Sjögren's syndrome: results of a phase III, randomised, placebo-controlled trial

OBJECTIVES

To evaluate efficacy and safety of abatacept in adults with active primary Sjögren's syndrome (pSS) in a phase III, randomised, double-blind, placebo-controlled trial.

METHODS

Eligible patients (moderate-to-severe pSS [2016 ACR/European League Against Rheumatism (EULAR) criteria], EULAR Sjögren's Syndrome Disease Activity Index [ESSDAI] ≥5, anti-SS-related antigen A/anti-Ro antibody positive) received weekly subcutaneous abatacept 125 mg or placebo for 169 days followed by an open-label extension to day 365. Primary endpoint was mean change from baseline in ESSDAI at day 169. Key secondary endpoints were mean change from baseline in EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) and stimulated whole salivary flow (SWSF) at day 169. Other secondary clinical endpoints included glandular functions and patient-reported outcomes. Selected biomarkers and immune cell phenotypes were examined. Safety was monitored.

RESULTS

Of 187 patients randomised, 168 completed double-blind period and 165 continued into open-label period. Mean (SD) baseline ESSDAI and ESSPRI total scores were 9.4 (4.3) and 6.5 (2.0), respectively. Statistical significance was not reached for primary (ESSDAI -3.2 abatacept vs -3.7 placebo, p=0.442) or key secondary endpoints (ESSPRI, p=0.337; SWSF, p=0.584). No clinical benefit of abatacept over placebo at day 169 was seen with other clinical and PRO endpoints. Relative to baseline, abatacept was associated with significant differences vs placebo in some disease-relevant biomarkers (including IgG, IgA, IgM-rheumatoid factor) and pathogenic cell subpopulations (post hoc analyses). No new safety signals were identified.

CONCLUSIONS

Abatacept treatment did not result in significant clinical efficacy compared with placebo in patients with moderate-to-severe pSS, despite evidence of biological activity.

Neutralizing antibody response against subcutaneously injected bacteriophages in rabbit model

Bacteriophage therapy is currently experiencing a renaissance. Therapeutic efficacy of bacteriophages depends on phage-bacterial and phage-host interactions. The appearance of neutralizing anti-phage antibody has been speculated to be one of the few reasons for bacteriophage therapy's failure. This study aimed to know whether there is a rise in the neutralizing antibody on the parenteral injection of bacteriophages in an animal model. This study included bacteriophages against five different bacteria, namely Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella Typhi and Staphylococcus aureus. These bacteriophages were isolated, propagated and purified. Bacteriophage specificity was confirmed by spot testing on the respective bacterial lawn. Weekly subcutaneous injection of purified bacteriophages (109PFU) was given to five rabbits for six weeks. Blood samples were collected before administering the next dose every week. The antibody response was tested by phage neutralization followed by plaque assay by using double agar overlay method. The rise in anti-phage neutralizing antibodies was observed usually after the 3rd week after immunization. Complete neutralization of bacteriophages could be seen between 3 and 5 weeks after immunization. A further rise in bacteriophage counts (PFU), especially on 1:1000 and 1:2000 serum dilutions, could be noticed by the end of 6th week against most bacteriophages injected. Background anti-phage neutralizing antibodies were observed against bacteriophage specific to Escherichia coli. However, it was absent against bacteriophages specific to other four bacteria. Bacteriophage interacts with mammalian host and induces anti-phages neutralizing antibody production. However, neutralization of phage depends on repeated administration and duration of therapy. The significant rise in neutralizing antibody could be seen at the end of 3rd week. Therefore, bacteriophage can be effectively used in acute cases where therapy duration is less than 2 weeks. However, for prolonged therapy, bacteriophage cocktail of different antigenicity may be suggested.

Innovative approaches to biologic development on the trail of CT-P13: biosimilars, value-added medicines, and biobetters

The biosimilar concept is now well established. Clinical data accumulated pre- and post-approval have supported biosimilar uptake, in turn stimulating competition in the biologics market and increasing patient access to biologics. Following technological advances, other innovative biologics, such as “biobetters” or “value-added medicines,” are now reaching the market. These innovative biologics differ from the reference product by offering additional clinical or non-clinical benefits. We discuss these innovative biologics with reference to CT-P13, initially available as an intravenous (IV) biosimilar of reference infliximab. A subcutaneous (SC) formulation, CT-P13 SC, has now been developed. Relative to CT-P13 IV, CT-P13 SC offers clinical benefits in terms of pharmacokinetics, with comparable efficacy, safety, and immunogenicity, as well as increased convenience for patients and reduced demands on healthcare system resources. As was once the case for biosimilars, nomenclature and regulatory pathways for innovative biologics require clarification to support their uptake and ultimately benefit patients.

Immunogenicity Challenges Associated with Subcutaneous Delivery of Therapeutic Proteins

The subcutaneous route of administration has provided convenient and non-inferior delivery of therapeutic proteins compared to intravenous infusion, but there is potential for enhanced immunogenicity toward subcutaneously administered proteins in a subset of patients. Unwanted anti-drug antibody response toward proteins or monoclonal antibodies upon repeated administration is shown to impact the pharmacokinetics and efficacy of multiple biologics. Unique immunogenicity challenges of the subcutaneous route have been realized through various preclinical and clinical examples, although subcutaneous delivery has often demonstrated comparable immunogenicity to intravenous administration. Beyond route of administration as a treatment-related factor of immunogenicity, certain product-related risk factors are particularly relevant to subcutaneously administered proteins. This review attempts to provide an overview of the mechanism of immune response toward proteins administered subcutaneously (subcutaneous proteins) and comments on product-related risk factors related to protein structure and stability, dosage form, and aggregation. A two-wave mechanism of antigen presentation in the immune response toward subcutaneous proteins is described, and interaction with dynamic antigen-presenting cells possessing high antigen processing efficiency and migratory activity may drive immunogenicity. Mitigation strategies for immunogenicity are discussed, including those in general use clinically and those currently in development. Mechanistic insights along with consideration of risk factors involved inspire theoretical strategies to provide antigen-specific, long-lasting effects for maintaining the safety and efficacy of therapeutic proteins.

Trial of Upadacitinib or Abatacept in Rheumatoid Arthritis

BACKGROUND

Upadacitinib is an oral selective Janus kinase inhibitor to treat rheumatoid arthritis. The efficacy and safety of upadacitinib as compared with abatacept, a T-cell costimulation modulator, in patients with rheumatoid arthritis refractory to biologic disease-modifying antirheumatic drugs (DMARDs) are unclear.

METHODS

In this 24-week, phase 3, double-blind, controlled trial, we randomly assigned patients in a 1:1 ratio to receive oral upadacitinib (15 mg once daily) or intravenous abatacept, each in combination with stable synthetic DMARDs. The primary end point was the change from baseline in the composite Disease Activity Score for 28 joints based on the C-reactive protein level (DAS28-CRP; range, 0 to 9.4, with higher scores indicating more disease activity) at week 12, assessed for noninferiority. Key secondary end points at week 12 were the superiority of upadacitinib over abatacept in the change from baseline in the DAS28-CRP and the percentage of patients having clinical remission according to a DAS28-CRP of less than 2.6.

RESULTS

A total of 303 patients received upadacitinib, and 309 patients received abatacept. From baseline DAS28-CRP values of 5.70 in the upadacitinib group and 5.88 in the abatacept group, the mean change at week 12 was -2.52 and -2.00, respectively (difference, -0.52 points; 95% confidence interval [CI], -0.69 to -0.35; P<0.001 for noninferiority; P<0.001 for superiority). The percentage of patients having remission was 30.0% with upadacitinib and 13.3% with abatacept (difference, 16.8 percentage points; 95% CI, 10.4 to 23.2; P<0.001 for superiority). During the treatment period, one death, one nonfatal stroke, and two venous thromboembolic events occurred in the upadacitinib group, and more patients in the upadacitinib group than in the abatacept group had elevated hepatic aminotransferase levels.

CONCLUSIONS

In patients with rheumatoid arthritis refractory to biologic DMARDs, upadacitinib was superior to abatacept in the change from baseline in the DAS28-CRP and the achievement of remission at week 12 but was associated with more serious adverse events. Longer and larger trials are required in order to determine the effect and safety of upadacitinib in patients with rheumatoid arthritis. (Funded by AbbVie; SELECT-CHOICE Clinicaltrials.gov number, NCT03086343.).

A critical review of the United States regulatory pathways for determining the equivalence of efficacy between CT-P13 and original infliximab (Remicade®)

We evaluated the appropriateness of various equivalence margins for CT-P13, an infliximab biosimilar, in the PLANETRA clinical trial. The 95-95% method was used to independently determine an equivalence margin by pooling the historical clinical trials with original infliximab versus placebo, identified in a systematic literature search. The constancy assumption with the PLANETRA trial was assessed for each identified historical clinical trial to decide which study was scientifically justifiable to be pooled. A sensitivity analysis was performed for each study-pooling scenario. As a result, we identified two historical clinical trials that were deemed appropriate, whereas the PLANETRA trial pooled three additional studies to determine an equivalence margin, which was accepted by the United States Food and Drug Administration. However, those extra clinical trials did not meet the constancy assumption in baseline characteristics, methotrexate dose, and efficacy assessment time. The clinically more appropriate equivalence margin was 5.7 percentage points, which was much narrower than the 12 percentage points applied in the approval of CT-P13. In conclusion, the equivalence claim for CT-P13 to original infliximab in patients with rheumatoid arthritis did not appear to be supported when the constancy assumption was strictly assessed. The equivalence margin for biosimilars could be determined more conservatively.

Does Abatacept Induce Testicular Toxicity?

OBJECTIVES

This study aims to demonstrate the effect of subcutaneous injections of abatacept on the histology of testes in mice.

MATERIALS AND METHODS

The study included 20 male BALB/c mice (average weight, 25 g; aged 12-14 weeks). Ten mice received subcutaneous (SC) injections of abatacept [0.25 mg per 25 g body weight per 0.03 mL normal saline (NS)] at zero, two, four and eight weeks. As the control group, 10 mice received SC injections of NS (0.03 mL). At the post-injection 10th week, the mice were sacrificed, and histopathological studies were conducted.

RESULTS

The results showed that 3/10 mice died of the abatacept-treated group. Testicular histology for the abatacept-treated group showed that 7/7 displayed no histopathological changes.

CONCLUSION

To our knowledge, this is the first control-blinded study of BALB/c mice suggesting that abatacept may not have testicular toxicity. Further fertility and testicular toxicology evaluations including semen analysis and gonadal hormones should be performed to clarify our findings.

CTLA4-Ig (abatacept): a promising investigational drug for use in type 1 diabetes

Introduction: Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of insulin-producing beta cells in the pancreas; it leads to the under or nonproduction of insulin. T1D is associated with numerous life-threatening micro- and macro-vascular complications and early deaths, hence the development of preventative strategies is a priority for research.Areas covered: The authors outline the drawbacks of available treatments for T1D and assess the three key strategies for prevention, including immunomodulatory therapies which hold the most potential. This article examines CTLA4-Ig and its efficacy and safety profiles. Finally, the pharmacokinetic parameters and pharmacodynamic markers of abatacept are shown in vivo and in clinical trials, guiding dosage regimen recommendations for future investigational studies.Expert opinion: Immunomodulation is one of the promising strategies for decelerating the progression of beta-cell destruction after the onset of T1D. It holds the advantage of specific immune modulation without systemic general immunosuppression. Preclinical and clinical studies have yielded promising data on the use of CTLA4-Ig in T1D. Variations in response to CTLA4-Ig might be partially explained by the existence of multiple T1D subtypes with varying baseline innate inflammatory/regulatory bias and the rate of C-peptide decline.

CTLA-4: From mechanism to autoimmune therapy

CD28 and CTLA-4 are both important stimulatory receptors for the regulation of T cell activation. Because receptors share common ligands, B7.1 and B7.2, the expression and biological function of CTLA-4 is important for the negative regulation of T cell responses. Therefore, elimination of CTLA-4 can result in the breakdown of immune tolerance and the development of several diseases such as autoimmunity. Inhibitory signals of CTLA-4 suppress T cell responses and protect against autoimmune diseases in many ways. In this review, we summarize the structure, expression and signaling pathway of CTLA-4. We also highlight how CTLA-4 defends against potentially self-reactive T cells. Finally, we discuss how the CTLA-4 regulates a number of autoimmune diseases that indicate manipulation of this inhibitory molecule is a promise as a strategy for the immunotherapy of autoimmune diseases.

Subcutaneous abatacept in rheumatoid arthritis: A real-life experience

Objectives

To assess the effectiveness, safety, and drug survival of subcutaneous (SC) abatacept (ABA) in a cohort of rheumatoid arthritis (RA) patients in a real-world setting.

Methods

This was a retrospective cohort study from 2014 to 2018 in which patients with RA (1987 ACR criteria) were included. Patients were evaluated at a single rheumatology outpatient center in Bogotá, Colombia. The patients were classified according to their treatment background: biological-naïve (n = 65), switched from IV to SC ABA administration (125 mg-wk) (n = 32), and inadequate response to biological DMARD (n = 62). The primary endpoint was a change in DAS28-CRP and RAPID3 from baseline to 12 months. A linear mixed effect model was used to correlate repeated measures. Adverse events were assessed and recorded during each visit to the rheumatology center. Several Cox proportional hazard regression models were used to test if there were any differences in drug survival curves based on seropositivity for rheumatoid factor (RF), and anti-Cyclic Citrullinated Peptide Antibodies (anti-CCP). Statistical analysis was done using software R version 3.4.4.

Results

A total of 159 patients were included. Baseline characteristics of patients were as follows: female gender 84%, median age of 54 years (IQR 16), median disease duration 10 years (11), RF positive 96%, anti-CCP positive 89%, erosive disease 55%, median DAS28-CRP 5.0 (2), and median RAPID3 17 (10). Concomitant use of methotrexate and SC ABA monotherapy were reported at 52% and 30% respectively. Demographics and disease characteristics were similar for all groups, except for baseline DAS28-CRP, and RAPID3 in the group that switched route of administration. The interaction between time and group was significant (p = 0.0073) for RAPID3. Infections, constitutional symptoms, and headaches were the most frequent AEs. Retention rate corresponded to 60% at 48 months. The most frequent reason for drug suspension was loss of efficacy. Median time of treatment for SC ABA was 31 months (IQR 30). The only association that reached statistical significance was anti-CCP concentration [Q1–Q4] (p = 0.005). According to the Cox proportional hazard regression model, there were significant differences between survival curves for Q1 (HR 0.15; 0.03–0.64 95% CI; p = 0.0096), and Q2 (HR 0.28; 0.08–0.92 95% CI; p = 0.0363) compared to the seronegative group.

Conclusions

The results showed an improvement in RA disease activity and physical function in patients under SC ABA treatment. Patients switching from IV to SC administration of ABA had lower activity and functional impairment at baseline. SC ABA demonstrated a good safety profile consistent with previously published data. Patients with baseline levels of anti-CCP antibody concentrations had better drug survival than seronegative patients.

•

Only a few studies have evaluated the effectiveness and safety of ABA in patients with RA in routine clinical practice.

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RAPID3 appears to be an attractive option for evaluating disease activity in RA patients in a real-life setting.

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SC administration of ABA demonstrates a safety profile consistent with previously published data.

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Prognostic factors for drug retention have not been explored thoroughly despite data for ABA being available from national registries.

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SC ABA survival tends to be better in a subset of anti-CCP seropositive patients with RA.

Abatacept as rescue immunosuppression after calcineurin inhibitor treatment failure in renal transplantation

A majority of kidney transplant recipients receive calcineurin inhibitor-based immunosuppression. However, some do not tolerate calcineurin inhibitors and require other immunosuppressive strategies. Until recently, alternative approaches have been associated with inferior outcomes, but recent methods have effectively utilized belatacept in calcineurin inhibitor-intolerant patients. Though promising, belatacept uptake has been limited by higher acute rejection rates, unavailability due to production shortages, and logistical challenges as a result of intravenous infusion requirements. Interestingly, its predecessor abatacept is clinically available in subcutaneous formulation to treat autoimmune disorders but has not been used in clinical transplantation. Here we report on a series of 9 calcineurin inhibitor-intolerant transplant recipients converted to abatacept early after transplant as rescue immunosuppression during periods of belatacept unavailability. Retrospective review revealed successful allograft salvage and 100% patient and graft survival (median 115 months) after conversion to abatacept. Patients received abatacept for a median duration of 82 months with stable, long-term renal allograft function, a single cellular rejection episode, and no clinically apparent protective immunity concerns. Hence our findings suggest that future clinical studies utilizing abatacept either de novo or as conversion therapy in transplant recipients should be considered.

Arthritis prevention in the pre-clinical phase of RA with abatacept (the APIPPRA study): a multi-centre, randomised, double-blind, parallel-group, placebo-controlled clinical trial protocol

TRIAL DESIGN

We present a study protocol for a multi-centre, randomised, double-blind, parallel-group, placebo-controlled trial that seeks to test the feasibility, acceptability and effectiveness of a 52-week period of treatment with the first-in-class co-stimulatory blocker abatacept for preventing or delaying the onset of inflammatory arthritis.

METHODS

The study aimed to recruit 206 male or female subjects from the secondary care hospital setting across the UK and the Netherlands. Participants who were at least 18 years old, who reported inflammatory sounding joint pain (clinically suspicious arthralgia) and who were found to be positive for serum autoantibodies associated with rheumatoid arthritis (RA) were eligible for enrolment. All study subjects were randomly assigned to receive weekly injections of investigational medicinal product, either abatacept or placebo treatment over the course of a 52-week period. Participants were followed up for a further 52 weeks. The primary endpoint was defined as the time to development of at least three swollen joints or to the fulfilment of the 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for RA using swollen but not tender joints, whichever endpoint was met first. In either case, swollen joints were confirmed by ultrasonography. Participants, care givers, and those assessing the outcomes were all blinded to group assignment. Clinical assessors and ultrasonographers were also blinded to each other's assessments for the duration of the study.

CONCLUSIONS

There is limited experience of the design and implementation of trials for the prevention of inflammatory joint diseases. We discuss the rationale behind choice and duration of treatment and the challenges associated with defining the "at risk" state and offer pragmatic solutions in the protocol to enrolling subjects at risk of RA.

TRIAL REGISTRATION

Current Controlled Trials, ID: ISRCTN46017566 . Registered on 4 July 2014.

Safety of abatacept compared with other biologic and conventional synthetic disease-modifying antirheumatic drugs in patients with rheumatoid arthritis: data from an observational study

Background

To assess the risks of malignancies, infections and autoimmune diseases in patients with rheumatoid arthritis (RA) treated with abatacept compared with other biologic (b) disease-modifying antirheumatic drugs (DMARDs) or conventional synthetic (cs)DMARDs, in a US-wide observational RA cohort

Methods

Data were reviewed from patients (≥ 18 years) with RA who were registered with FORWARD, the National Databank for Rheumatic Diseases, and who initiated abatacept, other bDMARDs or csDMARDs between 2005 and 2015. Patients who switched treatment during the study could be allocated to more than one group. The incidence rates (IRs) by treatment were calculated for malignancies, hospitalized infections and autoimmune diseases identified by six monthly questionnaires and medical records. The hazard ratios (HRs) (95% confidence intervals [CIs]) for all outcomes with abatacept compared with other bDMARDs or csDMARDs were determined using marginal structural models adjusted for clinical confounders.

Results

In the study sample, 1496 initiated abatacept, 3490 initiated another bDMARD and 1520 initiated a csDMARD. The risk of malignancies with abatacept was not statistically significant versus other bDMARDs (HR [95% CI)] 1.89 [0.93, 3.84]) or versus csDMARDs (HR [95% CI] 0.93 [0.20, 4.27]). Patients receiving abatacept versus other bDMARDs were at a lower risk of hospitalized infections (HR [95% CI] 0.37 [0.18, 0.75]); the risk versus csDMARDs was lower with wide CIs (HR [95% CI] 0.31 [0.09, 1.05]). The relative risks for psoriasis were similar between treatment groups (HR [95% CI] 1.46 [0.76, 2.81] and HR [95% CI] 2.05 [0.59, 7.16] for abatacept versus other bDMARDs and versus csDMARDS, respectively). The IR (95% CI) of severe infusion/injection reactions was lower with abatacept compared with other bDMARDs (1.57 [1.11, 2.17] vs 2.31 [1.87, 2.82] per 100 patient-years, respectively).

Conclusions

In this analysis, abatacept was well tolerated and did not result in an overall increased risk of malignancies, infections or autoimmune diseases compared with other bDMARDs or csDMARDs.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1921-z) contains supplementary material, which is available to authorized users.

Safety of Abatacept Versus Placebo in Rheumatoid Arthritis: Integrated Data Analysis of Nine Clinical Trials

Objective

To assess the safety of abatacept treatment in rheumatoid arthritis (RA) using integrated data from multiple clinical trials.

Methods

Data from nine double‐blind, placebo‐controlled studies of abatacept treatment (seven intravenous, two subcutaneous) in patients with RA were pooled, focusing on safety events in the double‐blind treatment period of each study. Incidence rates (IRs) of adverse events (AEs) per 100 patient‐years of exposure were calculated for abatacept‐ and placebo‐treated patients. AEs in abatacept‐treated patients were combined regardless of dose and formulation.

Results

In total, 2653 patients received abatacept and 1485 received placebo, with 2357 and 1254 patient‐years of exposure, respectively. The mean (SD) durations of exposure in the abatacept and placebo groups were 10.8 (3.3) and 10.3 (3.5) months, respectively. The IRs (95% confidence interval [CI]) for serious AEs were 14.8 (13.3, 16.5) and 14.6 (12.5, 17.0) in the abatacept and placebo groups, respectively. Death occurred in 12 (0.5%) and 12 (0.8%) patients in the abatacept and placebo groups, respectively, and was most commonly caused by cardiac disorders. Malignancies were observed in 31 patients (1.2%) treated with abatacept (IR: 1.32 [95% CI: 0.90, 1.87]) versus 14 (0.9%; IR: 1.12 [0.61, 1.88]) who received placebo. Solid organ tumor was the most frequent malignancy reported in both groups (abatacept: 1.0%; IR: 1.11 [95% CI: 0.72, 1.62]; placebo: 0.8%; 0.96 [0.50, 1.67]).

Conclusion

In this integrated analysis, the IRs of safety events in the abatacept and placebo groups were similar with no new safety concerns identified.

Abatacept for the treatment of rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a complex disease in which different mechanisms are involved. Studies suggest a key role for aberrant pathways of T-cell activation in the initiation and perpetuation of disease. Abatacept is a fusion protein composed of the Fc region of the immunoglobulin G1 (IgG1) fused to the extracellular domain of cytotoxic T lymphocyte-associated antigen (CTLA4). It has the ability to modulate T-cell activation by interfering with co-stimulation of these cells, a necessary step to become activated. This suggests that abatacept may play a role in the progression and/or even the initiation of RA. Areas covered: a review of the different studies carried out during clinical development of abatacept was performed. Both formulations, intravenous (IV) and subcutaneous (SC), showed a similar and consistent efficacy and safety profile. Abatacept was effective both in RA patients not responding to methotrexate (MTX) and to tumor necrosis factor (TNF) inhibitors. Expert commentary: abatacept, with its unique mechanism of action, proved to be a useful therapeutic alternative in RA, also having an acceptable safety profile. Evidence points out that abatacept may be able to alter the RA disease course. Ongoing studies will clarify this issue.

Beneficio económico de los ensayos clínicos controlados patrocinados: El gasto evitable en medicamentos para el tratamiento de la artritis reumatoidea

OBJECTIVES

To estimate the following: (1) the avoidable cost of biologic (bDMARDs) and conventional synthetic Rheumatoid Arthritis (RA) modifying antirheumatic drugs (csDMARDs) during controlled clinical trials (CCTs), their extension period, and for bDMARDs in post study drug programs; and (2) to evaluate the impact on health insurances.

METHODS

We analyzed 13 CCTs (233 patients) that evaluated bDMARDs. Avoidable cost was what the health insurance should have paid if the patient had not received the medication from the CCT sponsor and was estimated with a micro-costing approach (bottom-up method). Results were expressed as mean ± standard deviation (SD) or percentages. Approved by the Ethics Committee.

RESULTS

Mean age was 50.62 SD 11.8 years, 84% were women, 72% (n = 166) had health insurance. The mean annual cost of bDMARDs was US$ 30 567.40 while the cost for csDMARDs was US$ 104.90 during the CCTs. The mean annual cost in extension periods and post study drug programs for bDMARDs was US$ 36 016.20 and for csDMARs during the extension period was US$ 81.70. The avoidable cost for public health insurances exceeded one million dollars per year.

CONCLUSION

This work describes for the first time in Argentina the significant economic benefit that may represent for RA patients' health insurances the participation in CCTs with bDMARDs. It shows that during the execution of the CCT, its extension periods, or post study access programs, while medication provision is guaranteed, the economic burden imposed by the treatment of the RA is relieved.

Subcutaneous Administration of Biotherapeutics: An Overview of Current Challenges and Opportunities

Subcutaneous delivery of biotherapeutics has become a valuable alternative to intravenous administration across many disease areas. Although the pharmacokinetic profiles of subcutaneous and intravenous formulations differ, subcutaneous administration has proven effective, safe, well-tolerated, generally preferred by patients and healthcare providers and to result in reduced drug delivery-related healthcare costs and resource use. The aim of this article is to discuss the differences between subcutaneous and intravenous dosing from both health-economic and scientific perspectives. The article covers different indications, treatment settings, administration volumes, and injection devices. We focus on biotherapeutics in rheumatoid arthritis (RA), immunoglobulin-replacement therapy in primary immunodeficiency (PI), beta interferons in multiple sclerosis (MS), and monoclonal antibodies (mAbs) in oncology. While most subcutaneous biotherapeutics in RA, PI, and MS are self-administered at home, mAbs for oncology are still only approved for administration in a healthcare setting. Beside concerns around the safety of biotherapeutics in oncology, a key challenge for self-administration in this area is that doses and dosing volumes can be comparatively large; however, this difficulty has recently been overcome to some extent by the development of high-concentration solutions, the use of infusion pumps, and the coadministration of the dispersion enhancer hyaluronidase. Furthermore, given the increasing number of biotherapeutics being considered for combination therapy and the high dosing complexity associated with these, especially when administered intravenously, subcutaneous delivery of fixed-dose combinations might be an alternative that will diminish these burdens on healthcare systems.