The Inhibition of Complement System in Formal and Emerging Indications: Results from Parallel One-Stage Pairwise and Network Meta-Analyses of Clinical Trials and Real-Life Data Studies

Network meta-analysis of pharmacological treatment for antibody-mediated rejection after organ transplantation

Objective

This study aims to assess the efficacy of pharmacological interventions in mitigating graft injury in transplant patients with antibody-mediated rejection (AMR) through a network meta-analysis (NMA).

Methods

A search was conducted on databases such as Cochrane Library, PubMed, EmBase, and Web of Science for randomized controlled trials (RCTs) on pharmacological interventions for alleviating graft injury following AMR. The search was performed for publications up to April 12, 2024. Two reviewers conducted independent reviews of the literature, extracted data, and assessed the risk of bias (ROB) in the included studies using the ROB assessment tool recommended by the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0. A Bayesian NMA was conducted using R 4.4.0, RStudio software, and the GeMTC package to assess the outcomes in estimated glomerular filtration rate (eGFR), mean fluorescence intensity (MFI), g-score, and infection under pharmacological treatments.

Results

A total of 8 RCTs involving 215 patients and 6 different pharmacological treatments were included in this NMA. The results indicated that the increase in eGFR by eculizumab (SUCRA score: 81) appeared to be more promising. The decrease in MFI by bortezomib (SUCRA score: 72.3), rituximab (SUCRA score: 68.2), and clazakizumab (SUCRA score: 67.1) demonstrated better efficacy. The decrease in g-score by eculizumab (SUCRA score: 74.3), clazakizumab (SUCRA score: 72.2), and C1INH (SUCRA score: 63.6) appeared to have more likelihood. For infection reduction, clazakizumab (SUCRA score: 83.5) and bortezomib (SUCRA score: 66.8) might be better choices.

Conclusion

The results of this study indicate that eculizumab has the potential to enhance eGFR and reduce g-score. Bortezomib demonstrates superior efficacy in reducing MFI. Clazakizumab appears to be more effective in reducing infections.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024546483.

Treatment preference and quality of life impact: ravulizumab vs eculizumab for atypical hemolytic uremic syndrome

Aim: Ravulizumab and eculizumab are complement C5 inhibitors approved for the treatment of atypical hemolytic uremic syndrome (aHUS). Ravulizumab requires less frequent infusions than eculizumab, which may reduce treatment burden. This study investigated patients' treatment preferences and the impact of both treatments on patient and caregiver quality of life. Materials & methods: Two surveys were conducted (one for adult patients with aHUS and one for caregivers of pediatric patients with aHUS) to quantitatively assess treatment preference and the patient- and caregiver-reported impact of ravulizumab and eculizumab on quality of life. Patients were required to have a diagnosis of aHUS, to be currently receiving treatment with ravulizumab and to have received prior treatment with eculizumab. Participants were recruited via various sources: the Alexion OneSource™ patient support program, the Rare Patient Voice recruitment agency, the aHUS Foundation and directly via a clinician involved in the study. Results: In total, 50 adult patients (mean age: 46.5 years) and 16 caregivers of pediatric patients (mean age: 10.1 years) completed the surveys. Most adult patients (94.0%) and all caregivers reported an overall preference for ravulizumab over eculizumab; infusion frequency was one of the main factors for patients when selecting their preferred treatment. Fewer patients reported disruption to daily life and the ability to go to work/school due to ravulizumab infusion frequency (4.0% and 5.7%, respectively) than eculizumab infusion frequency (72.0% and 60.0%), with similar results for caregivers. Conclusion: Adult patients and caregivers of pediatric patients indicated an overall preference for ravulizumab than eculizumab for the treatment of aHUS, driven primarily by infusion frequency. This study contributes to the emerging real-world evidence on the treatment impact and preference in patients with aHUS.

Atypical Hemolytic Uremic Syndrome Treated With Ravulizumab or Eculizumab: A Claims-Based Evaluation of Health Care Resource Utilization and Clinical Outcomes in the United States

Rationale and Objective

Ravulizumab and eculizumab have shown efficacy for the treatment of atypical hemolytic uremic syndrome (aHUS), but real-world evidence for ravulizumab is limited owing to its more recent approval. This real-world database study examined outcomes for adult patients switching to ravulizumab from eculizumab and patients treated with individual treatments.

Study Design

A retrospective, observational study using the Clarivate Real World Database.

Setting and Population

US health-insurance billing data (January 2012 to March 2021) of patients aged 18 years or older with ≥1 diagnosis relevant to aHUS, ≥1 claim for treatment with eculizumab or ravulizumab, and no evidence of other indicated conditions.

Exposures

Treatment-switch (to ravulizumab after eculizumab), ravulizumab-only, and eculizumab-only cohorts were examined.

Outcomes

Clinical procedures, facility visits, health care costs, and clinical manifestations.

Analytical Approach

Paired-sample statistical testing compared the mean numbers of claims for each group 0-3 months before (preindex period) and 0-3 months and 3-6 months after (postindex period) the index date (point of initiation with a single treatment or treatment switch).

Results

In total, 322 patients met the eligibility criteria at 3-6 months postindex in the treatment-switch (n=65), ravulizumab-only (n=9), and eculizumab-only (n=248) cohorts. The proportions of patients with claims for key clinical procedures continued to be small after treatment switch and were small (0%-11%) across all cohorts at 3-6 months postindex. Inpatient visits were reduced in the postindex period across all cohorts. At 3-6 months after treatment switch, patients reported fewer claims for outpatient, private practice, and home visits and lower median health care costs. The proportions of patients with claims for clinical manifestations of aHUS were generally reduced in the postindex period compared with those of the preindex period.

Limitations

Low patient numbers receiving ravulizumab only.

Conclusions

The health-insurance claims data showed a reduced health care burden for US adult patients after treatment with ravulizumab or eculizumab for treatment of aHUS.

Research advances in treatment methods and drug development for rare diseases

As the incidence of rare diseases increases each year, the total number of rare disease patients worldwide is nearly 400 million. Orphan medications are drugs used to treat rare diseases. Orphan drugs, however, are rare and patients often struggle to utilize them and expensive medications during treatment. Orphan drugs have been the focus of new drug research and development for both domestic and international pharmaceutical companies as a result of the substantial investment being made in the field of rare diseases. Clinical breakthroughs have been made in every field, from traditional antibodies and small molecule drugs to gene therapy, stem cell therapy and small nucleic acid drugs. We here review the therapeutic means of rare diseases and drug development of rare diseases to show the progress of treatment of rare diseases in order to provide a reference for clinical use and new drug development of rare diseases in China.

Quantifying the economic effects of ravulizumab versus eculizumab treatment in patients with atypical hemolytic uremic syndrome

AIMS

This study compared the aggregate duration of treatment administration of approved eculizumab and ravulizumab treatment regimens and resultant productivity implications for patients with atypical hemolytic uremic syndrome (aHUS) and their caregivers.

METHODS

The aggregate duration of treatment administration (which includes waiting time for medication preparation and time for infusion, recovery, and travel to and from the clinic) was determined for a hypothetical population of patients with aHUS treated with eculizumab (10 mg/mL) or ravulizumab (10 or 100 mg/mL), in the clinic or at home, for 1 year, in Germany, Italy, the UK, and the US. The data for US patients treated in the clinic was used to extend a previously published cost-minimization model (CMM) to estimate the annual lost productivity associated with treatment administration and to compare the overall annual treatment costs for hypothetical adult and pediatric patients in the US.

RESULTS

The aggregate duration of treatment administration associated with ravulizumab 10 mg/mL and 100 mg/mL was reduced by 44-52% and 69-74%, respectively, compared with eculizumab 10 mg/mL, across all four countries. Using the CMM, the adult and pediatric US patient lost productivity costs due to treatment were reduced by 56-60% and 73-76% with ravulizumab 10 mg/mL and 100 mg/mL, respectively, compared with eculizumab 10 mg/mL, and overall discounted annual treatment costs (direct and lost productivity costs owing to treatment) were reduced for ravulizumab (10 mg/mL and 100 mg/mL) vs eculizumab 10 mg/mL for adult and pediatric patients.

LIMITATIONS

This study was based on hypothetical patients, and assumptions were made regarding caregiver involvement, patient characteristics, and treatment patterns.

CONCLUSIONS

Compared with eculizumab, ravulizumab reduces the lost productivity costs associated with treatment. This reduction in costs is greater with the ravulizumab 100 mg/mL formulation, compared with ravulizumab 10 mg/mL, owing to shorter infusion times with this more concentrated formulation.

Complement Activation Fragments Are Increased in Critically Ill Pediatric Patients with Severe AKI

Background

Children who are critically ill with AKI suffer from high morbidity and mortality rates, and lack treatment options. Emerging evidence implicates the role of complement activation in AKI pathogenesis, which could potentially be treated with complement inhibitors. The purpose of this study is to evaluate the association between complement activation fragments and severity of AKI in children who are critically ill.

Methods

A biorepository of samples from children who are critically ill from a prior multisite study was leveraged to identify children with stage 3 AKI and matched to patients without AKI on the basis of PELOD-2 (illness severity) scores. Specimens were analyzed for plasma and urine complement activation fragments of factor B, C3a, C4a, and sC5b-9. The primary outcomes were MAKE30 and severe AKI rates.

Results

In total, 14 patients with stage 3 AKI (five requiring RRT) were matched to 14 patients without AKI. Urine factor Ba and plasma C4a levels increased stepwise as severity of AKI increased, from no AKI to stage 3 AKI, to stage 3 AKI with RRT need. Plasma C4a levels were independently associated with increased risk of MAKE30 outcomes (OR, 3.2; IQR, 1.1-8.9), and urine Ba (OR, 1.9; IQR, 1.1-3.1), plasma Bb (OR, 2.7; IQR, 1.1-6.8), C4a (OR, 13.0; IQR, 1.6-106.6), and C3a (OR, 3.3; IQR, 1.3-8.4) were independently associated with risk of severe stage 2-3 AKI on day 3 of admission.

Conclusions

Multiple complement fragments increase as magnitude of AKI severity increases. Very high levels of urine Ba or plasma C4a may identify patients at risk for severe AKI, hemodialysis, and MAKE30 outcomes. The fragments may be useful as a functional biomarker of complement activation and may identify those patients to study complement inhibition to treat or prevent AKI in children who are critically ill. These findings suggest the need for further specific investigations of the role of complement activation in children who are critically ill and at risk of AKI.

Binding Potassium to Improve Treatment With Renin-Angiotensin-Aldosterone System Inhibitors: Results From Multiple One-Stage Pairwise and Network Meta-Analyses of Clinical Trials

This manuscript presents findings from the first dichotomous data pooling analysis on clinical trials (CT) regarding the effectiveness of binding potassium. The results emanated from pairwise and network meta-analyses aiming evaluation of response to commercial potassium-binding polymers, that is, to achieve and maintain normal serum potassium (n = 1,722), and the association between this response and an optimal dosing of renin-angiotensin-aldosterone system inhibitors (RAASi) needing individuals affected by heart failure (HF) or resistant hypertension, who may be consuming other hyperkalemia-inducing drugs (HKID) (e.g., β-blockers, heparin, etc.), and frequently are affected by chronic kidney disease (CKD) (n = 1,044): According to the surface under the cumulative ranking area (SUCRA), sodium zirconium cyclosilicate (SZC) (SUCRA >0.78), patiromer (SUCRA >0.58) and sodium polystyrene sulfonate (SPS) (SUCRA <0.39) were different concerning their capacity to achieve normokalemia (serum potassium level (sK+) 3.5-5.0 mEq/L) or acceptable kalemia (sK+ ≤ 5.1 mEq/L) in individuals with hyperkalemia (sK+ >5.1 mEq/L), and, when normokalemia is achieved, patiromer 16.8-25.2 g/day (SUCRA = 0.94) and patiromer 8.4-16.8 g/day (SUCRA = 0.41) can allow to increase the dose of spironolactone up to 50 mg/day in subjects affected by heart failure (HF) or with resistant hypertension needing treatment with other RAASi. The potential of zirconium cyclosilicate should be explored further, as no data exists to assess properly its capacity to optimize dosing of RAASi, contrarily as it occurs with patiromer. More research is also necessary to discern between benefits of binding potassium among all type of hyperkalemic patients, for example, patients with DM who may need treatment for proteinuria, patients with early hypertension, etc. Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42020185614, CRD42020185558, CRD42020191430.

Healthcare Data for Achieving a More Personalized Treatment of Chronic Kidney Disease

The current concept of healthcare incites a more personalized treatment of diseases. To this aim, biomarkers are needed to improve decision-making facing chronic kidney disease (CKD) patients. Prognostic markers provided by real-world (observational) evidence are proposed in this Special Issue entitled "Biomarkers in Chronic Kidney Disease", with the intention to identify high-risk patients. These markers do not target measurable parameters in patients but clinical endpoints that may be in turn transformed to benefits under the effect of future interventions.

Immunopathology of Type 1 Diabetes and Immunomodulatory Effects of Stem Cells: A Narrative Review of the Literature

Type 1 Diabetes (T1D) is a complex autoimmune disorder which occurs as a result of an intricate series of pathologic interactions between pancreatic β-cells and a wide range of components of both the innate and the adaptive immune systems. Stem-cell therapy, a recently-emerged potentially therapeutic option for curative treatment of diabetes, is demonstrated to cause significant alternations to both different immune cells such as macrophages, natural killer (NK) cells, dendritic cells, T cells, and B cells and non-cellular elements including serum cytokines and different components of the complement system. Although there exists overwhelming evidence indicating that the documented therapeutic effects of stem cells on patients with T1D is primarily due to their potential for immune regulation rather than pancreatic tissue regeneration, to date, the precise underlying mechanisms remain obscure. On the other hand, immune-mediated rejection of stem cells remains one of the main obstacles to regenerative medicine. Moreover, the consequences of efferocytosis of stem-cells by the recipients' lung-resident macrophages have recently emerged as a responsible mechanism for some immune-mediated therapeutic effects of stem-cells. This review focuses on the nature of the interactions amongst different compartments of the immune systems which are involved in the pathogenesis of T1D and provides explanation as to how stem cell-based interventions can influence immune system and maintain the physiologic equilibrium.