Efficacy and Safety of Eculizumab in Pediatric Patients Affected by Shiga Toxin-Related Hemolytic and Uremic Syndrome: A Randomized, Placebo-Controlled Trial

SIGNIFICANCE STATEMENT

Shiga toxin-related hemolytic uremic syndrome (STEC-HUS) is a serious condition, characterized by multiorgan thrombotic microangiopathy, mainly affecting children. Renal involvement is severe, with approximately half of patients requiring dialysis. So far, no specific treatment has been proven efficient in STEC-HUS. The use of eculizumab, a monoclonal antibody inhibiting terminal complement complex, has demonstrated remarkable success in atypical hemolytic uremic syndrome, but its use in uncontrolled studies to treat STEC-HUS has yielded inconsistent results. In this Phase 3 randomized, placebo-controlled trial in 100 pediatric patients with STEC-HUS, the findings did not show efficacy of eculizumab during the acute phase of the disease. However, the results indicated a reduction of renal sequelae in eculizumab-treated patients at 1-year follow-up. Larger prospective studies would be needed to further explore eculizumab as a potential treatment.

BACKGROUND

Shiga toxin-related hemolytic uremic syndrome (STEC-HUS) in children is a severe condition, resulting in approximately 50% of patients requiring RRT. Furthermore, at least 30% of survivors experience kidney sequelae. Recently, activation of the complement alternative pathway has been postulated as a factor in STEC-HUS pathophysiology, leading to compassionate use of eculizumab, a monoclonal antibody inhibiting the terminal complement complex, in affected patients. Given the lack of therapy for STEC-HUS, a controlled study of eculizumab efficacy in treating this condition is a priority.

METHODS

We conducted a Phase 3 randomized trial of eculizumab in children with STEC-HUS. Patients were randomly assigned in a 1:1 ratio to receive either eculizumab or placebo during 4 weeks. Follow-up lasted for 1 year. The primary end point was RRT duration <48 hours after randomization. Secondary endpoints included hematologic and extrarenal involvement.

RESULTS

Baseline characteristics were similar among the 100 patients who underwent randomization. The rate of RRT <48 hours did not differ significantly between the two groups (48% in the placebo versus 38% in the eculizumab group; P = 0.31) or in the course of ARF. The two groups also exhibited similar hematologic evolution and extrarenal manifestations of STEC-HUS. The proportion of patients experiencing renal sequelae at 1 year was lower in the eculizumab group than in the placebo group (43.48% and 64.44%, respectively, P = 0.04). No safety concern was reported.

CONCLUSIONS

In pediatric patients with STEC-HUS, eculizumab treatment does not appear to be associated with improved renal outcome during acute phase of the disease but may reduce long-term kidney sequelae.

CLINICAL TRIALS REGISTRATIONS

EUDRACT (2014-001169-28) ClinicalTrials.gov ( NCT02205541 ).

Plasma MCP-1 and changes on cognitive function in community-dwelling older adults

Background

Monocyte Chemoattractant Protein-1 (MCP-1), a glial-derived chemokine, mediates neuroinflammation and may regulate memory outcomes among older adults. We aimed to explore the associations of plasma MCP-1 levels (alone and in combination with β-amyloid deposition—Aβ_42/40) with overall and domain-specific cognitive evolution among older adults.

Methods

Secondary analyses including 1097 subjects (mean age = 75.3 years ± 4.4; 63.8% women) from the Multidomain Alzheimer Preventive Trial (MAPT). MCP-1 (higher is worse) and Aβ_42/40 (lower is worse) were measured in plasma collected at year 1. MCP-1 in continuous and as a dichotomy (values in the highest quartile (MCP-1⁺)) were used, as well as a dichotomy of Aβ_42/40. Outcomes were measured annually over 4 years and included the following: cognitive composite z-score (CCS), the Mini-Mental State Examination (MMSE), and Clinical Dementia Rating (CDR) sum of boxes (overall cognitive function); composite executive function z-score, composite attention z-score, Free and Cued Selective Reminding Test (FCSRT - memory).

Results

Plasma MCP-1 as a continuous variable was associated with the worsening of episodic memory over 4 years of follow-up, specifically in measures of free and cued delayed recall. MCP-1⁺ was associated with worse evolution in the CCS (4-year between-group difference: β = −0.14, 95%CI = −0.26, −0.02) and the CDR sum of boxes (2-year: β = 0.19, 95%CI = 0.06, 0.32). In domain-specific analyses, MCP-1⁺ was associated with declines in the FCSRT delayed recall sub-domains. In the presence of low Aβ_42/40, MCP-1⁺ was not associated with greater declines in cognitive functions. The interaction with continuous biomarker values Aβ_42/40× MCP-1 × time was significant in models with CDR sum of boxes and FCSRT DTR as dependent variables.

Conclusions

Baseline plasma MCP-1 levels were associated with longitudinal declines in overall cognitive and episodic memory performance in older adults over a 4-year follow-up. How plasma MCP-1 interacts with Aβ_42/40 to determine cognitive decline at different stages of cognitive decline/dementia should be clarified by further research. The MCP-1 association on cognitive decline was strongest in those with amyloid plaques, as measured by blood plasma Aβ_42/40.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00940-2.

Biomarkers of mitochondrial dysfunction and inflammaging in older adults and blood pressure variability

Most physiopathological mechanisms underlying blood pressure variability (BPV) are implicated in aging. Vascular aging is associated with chronic low-grade inflammation occurring in late life, known as "inflammaging" and the hallmark "mitochondrial dysfunction" due to age-related stress. We aimed to determine whether plasma levels of the pleiotropic stress-related mitokine growth/differentiation factor 15 (GDF-15) and two inflammatory biomarkers, interleukin 6 (IL-6) and tumor necrosis factor receptor 1 (TNFR-1), are associated with visit-to-visit BPV in a population of community-dwelling older adults. The study population consisted of 1096 community-dwelling participants [median age 75 (72-78) years; 699 females, 63.7%] aged ≥ 70 years from the MAPT study. Plasma blood sample was collected 12 months after enrolment and BP was assessed up to seven times over a 4-year period. Systolic (SBPV) and diastolic BPV (DBPV) were determined through several indicators taking into account BP change over time, the order of measurements and formulas independent of mean BP levels. Higher values of GDF-15 were significantly associated with increased SBPV (all indicators) after adjustment for relevant covariates [adjusted 1-SD increase in GDF-15: β (SE) = 0.07 (0.04), p < 0.044, for coefficient of variation%]. GDF-15 levels were not associated with DBPV. No significant associations were found between IL-6 and BPV, whereas TNFR1 was only partially related to DBPV. Unlike inflammation biomarkers, higher GDF-15 levels were associated with greater SBPV. Our findings support the age-related process of mitochondrial dysfunction underlying BP instability, suggesting that BPV might be a potential marker of aging.

[Medication errors reporting in drug clinical trials: Role of the clinical research pharmacist?]

The investigational drugs circuit has specific risks, and medication errors may occur in clinical trials, possibly associated with adverse reactions. These risks must therefore be managed. In fact, there are few reports of medication errors during clinical trials. In a context of regulatory interpretation difficulties on this subject, we conducted a national survey that highlighted the heterogeneity of the methods used by academic sponsors to collect, code and report medication errors and the need to develop a culture of reporting these errors in clinical trials. This is why the REVISE group (safety officers of French institutional sponsors) has issued recommendations to clarify the sponsor and investigator responsibilities and guide them in the management of medication errors. These new guidelines recommend that any serious or potentially serious medication error or other "special situation" (e.g. overdose, misuse, quality defect) should be notified immediately to the sponsor by the investigator. The clinical research pharmacist place is strategic to detect medication errors and other special situations. The integration of the pharmacist into the reporting system, in collaboration with the investigator, could be discussed with clinical research professionals and health authorities.

Compliance of French academic clinical trials with the Clinical Trial Facilitation and Coordination Group recommendations on contraception and pregnancy testing requirements

BACKGROUND/AIMS

The Clinical Trials Coordination and Facilitation Group has issued recommendations on contraception and pregnancy testing to help sponsors meet regulatory expectations and harmonize practices to limit embryofetal risks in clinical trials. Our objective was to assess the compliance of French academic clinical trials with these recommendations and to describe the mitigation measures required by sponsors in their trials.

METHODS

A cross-sectional study was performed on the French academic drug trials authorized by the national competent authority between January 2015 and June 2018. We included trials which tested systemic administration of drugs and enrolled men or women of childbearing potential.

RESULTS

Data from 97 trials included were compiled. One-third of the trials (23.8%-43.3%, 95% confidence interval) complied with the Clinical Trial Facilitation and Coordination Group recommendations. No improvement over time or according to embryofetotoxic status or drug duration exposure was found. Contraception was required in 56.7% of trials and was more often required in case of potentially embryofetotoxic drugs (68.5% vs 41.9%, p = 0.013) or exposure over 1 month (71.7% vs 43.8%, p = 0.006). Pregnancy testing at inclusion was required in 59.1% of trials and additional testing in 17.2%. Pregnancy testing at inclusion was more often required in trials with drug exposure above 1 month (67.4% vs 45.8%, p = 0.035).

CONCLUSION

French academic sponsors barely met the recommendations on contraception and pregnancy testing potentially leading to potential embryofetal risks in case of pregnancy. They need to implement these recommendations quickly.

Is spontaneous reporting always the most important information supporting drug withdrawals for pharmacovigilance reasons in France?

PURPOSE

The objective of our study was to determine the nature of scientific evidence leading to drug withdrawal for safety reasons in France (between 2005 and 2011).

METHODS

Drugs (i.e., active ingredients) withdrawn were identified from the Web site of the French Health Products Agency. Additional information allowed us to classify these withdrawals according to the nature of evidence as clinical trials (CT), case reports/case series (CR/CS), case-control studies (CC), cohort, animal, or observational studies.

RESULTS

A total of 22 active ingredients were withdrawn from the French market between 2005 and 2011. The nature and type of adverse drug reactions (ADRs) leading more frequently to drug withdrawal were cardiovascular (10-fold), neurological (5-fold), or hepatic, cutaneous, or psychiatric (3-fold each) ADRs. CR (19/22; 86.4%) and CT (13/22; 59.1%) were the most frequently involved methods. In 5 of 22 (23%) cases, CR were the sole evidence. However, 68% (15/22) of regulatory decisions were based on multiple sources of evidence: For example, data from CR + CT were used in eight cases. CC or cohort studies were used in only five cases.

CONCLUSION

This study underlines that spontaneous reporting remained the most important source of drug withdrawals between 2005 and 2011. However, its relative importance decreased in comparison with that in 1997-2004. The importance of pharmacoepidemiological methods slightly increased but remained low. Finally, regulatory authorities seem to have more frequently based their safety decisions on multiple sources of evidence than before.