Therapeutic Drug Monitoring in Patients with Systemic Lupus Erythematosus: Utility and Gaps

Despite advances in the treatment of patients with systemic lupus erythematous (SLE), outcomes have remained suboptimal. Persistent disease activity, patient comorbidities and drug toxicities contribute to the accrual of progressive irreversible damage and high rates of morbidity and mortality. Currently, similar drug doses and regimens are promulgated in the treatment guidelines for all SLE patients, despite the vast differences in patient and environmental factors that affect the drugs' metabolism and blood concentrations. This causes a disconnect between drug dosing and drug blood concentrations, which can then result in unpredictability in drug toxicities and therapeutic effects. In this review, we discuss commonly used oral immunosuppressive medications in SLE, their pharmacogenomics, and factors affecting their metabolism and blood concentrations. Further, we highlight the role of therapeutic drug monitoring in SLE, which is the first accessible step to individualising therapy.

Neoantigen Cancer Vaccine for Immunologically Cold Microsatellite-stable Colorectal Cancer

PURPOSE/OBJECTIVE(S)

Immunotherapies, such as immune checkpoint inhibitors (ICIs), have revolutionized management of some cancers but have little benefit for microsatellite-stable colorectal cancer patients (MSS-CRC). This is, in part, due to the low mutations and neoantigen expression in this immunogenically "cold" MSS-CRC. Therefore, we aim to develop novel shared neoantigen-based therapeutic cancer vaccine to reinvigorate antitumor immunity and enhance the therapeutic benefit of radiotherapy in MSS-CRC.

MATERIALS/METHODS

To identify novel highly expressed and shared neoantigens, we collected 40 match-paired adjacent normal and tumor tissues from MSS-CRC patients for WES-seq, RNA-seq, and liquid chromatography-MS/MS (LC-MS/MS). By incorporating these databases, we established Neoantigen Discovery and Validation (NeoDiva) system to identify a cluster of highly expressed and shared neoantigens derived from non-coding regions and evaluate its immunogenicity by HLA-A*11 transgenic mice. We then develop a neoantigen-based therapeutic cancer vaccine by an engineered adenovirus-associated virus (AAV) to evaluate its therapeutic efficacy in combination with radiotherapy in MSS-CRC animal model.

RESULTS

We identified a cluster of highly expressed and shared neoantigens (HLA-A*11-restricted) derived from non-coding regions. The immunogenicity of these novel neoantigens was demonstrated by HLA-A*11 transgenic mice and ex vivo stimulation. Moreover, the engineered AAV-based neoantigen cancer vaccine significantly eradicates cancer cells, prevents distant metastasis, prolong survival period in combination with radiotherapy. By flow cytometry, ELISPOT and MHC-I-tetramer assay, we demonstrated the recruitment of tumor-infiltrating lymphocytes was remarkably increased and neoantigen-specific T cell response was enhanced. Moreover, these isolated neoantigen-specific T cells can recognize cancer cells and produce IFNg to kill cancer cells.

CONCLUSION

Neoantigens identified by our NeoDiVa platform, via the combination of radiotherapy and a novel AAV vaccine delivery system, boosted antigen-specific T-cell function and improve tumor control of limnologically "cold" MSS colorectal cancer in vivo. We are in the process of obtaining an IND and initiating Phase I/II clinical trial to validate safety and efficacy of these exciting findings.

Elevated Urinary Tissue Inhibitor Of Metalloproteinase-2 And Insulin-Like Growth Factor Binding Protein-7 Predict Drug-Induced Acute Kidney Injury

BACKGROUND

Urinary tissue inhibitor of metalloproteinase-2 (TIMP2) and insulin-like growth factor binding protein-7 (IGFBP7) predict severe acute kidney injury (AKI) in critical illness. Earlier but subtle elevation of either biomarker from nephrotoxicity may predict drug-induced AKI.

METHODS

A prospective study involving serial urine collection in patients treated with vancomycin, aminoglycosides, amphotericin, foscarnet, or calcineurin inhibitors was performed. Urinary TIMP2 and IGFBP7, absolute levels, normalized with urine creatinine were examined in days leading to AKI onset by KDIGO criteria in cases, or at final day of nephrotoxic therapy in non-AKI controls who were matched for age, baseline kidney function and nephrotoxic exposure.

RESULTS

Urinary biomarker analyses were performed in 21 AKI patients and 28 non-AKI matched-controls; both groups had comparable baseline kidney function and duration of nephrotoxic drug therapy. Significantly higher absolute, normalized, and composite levels of TIMP2 and IGFBP7 were observed in AKI cases versus controls as early as 2-3 days before AKI onset (all P<0.05); >70% of patients with corresponding levels above 75th percentile developed AKI. Normalized TIMP2 at 2-3 days pre-AKI predicted AKI with the highest average AUROC of 0.81, followed by that of composite [TIMP2]x[IGFBP7] (0.78) after cross-validation. [TIMP2]x[IGFBP7] >0.01 (ng/mL)2 /1000 predicted AKI with a sensitivity of 79% and specificity of 60%.

CONCLUSION

Elevated urinary TIMP2 or IGFBP7 predicts drug-induced AKI with a lead-time of 2-3 days; an opportune time for interventions to reduce nephrotoxicity.

Ensuring Sustainability of Continuous Kidney Replacement Therapy in the Face of Extraordinary Demand: Lessons From the COVID-19 Pandemic

With the exponential surge in patients with coronavirus disease 2019 (COVID-19) worldwide, the resources needed to provide continuous kidney replacement therapy (CKRT) for patients with acute kidney injury or kidney failure may be threatened. This article summarizes subsisting strategies that can be implemented immediately. Pre-emptive weekly multicenter projections of CKRT demand based on evolving COVID-19 epidemiology and routine workload should be made. Corresponding consumables should be quantified and acquired, with diversification of sources from multiple vendors. Supply procurement should be stepped up accordingly so that a several-week stock is amassed, with administrative oversight to prevent disproportionate hoarding by institutions. Consumption of CKRT resources can be made more efficient by optimizing circuit anticoagulation to preserve filters, extending use of each vascular access, lowering blood flows to reduce citrate consumption, moderating the CKRT intensity to conserve fluids, or running accelerated KRT at higher clearance to treat more patients per machine. If logistically feasible, earlier transition to intermittent hemodialysis with online-generated dialysate, or urgent peritoneal dialysis in selected patients, may help reduce CKRT dependency. These measures, coupled to multicenter collaboration and a corresponding increase in trained medical and nursing staffing levels, may avoid downstream rationing of care and save lives during the peak of the pandemic.

Transitional care program to facilitate recovery following severe acute kidney injury

BACKGROUND

Patients with acute kidney injury needing prolonged renal replacement therapy (AKI-RRT) may benefit from a structured care process in form of an AKI transitional care program (ATCP), to facilitate RRT weaning and recovery.

METHODS

We examined outcomes following ATCP implementation in adults with AKI-RRT from a tertiary institution (versus pre-ATCP controls), including mortality, cumulative hospital days, and renal function over one year; RRT and haemodialysis catheter days in initial 90 days.

RESULTS

We studied 89 patients with age 62 ( ± 15) years. 47% had septic AKI, 20% cardiorenal syndrome, and 29% had baseline eGFR < 30 mL/min/1.73 m². Comparing 45 ATCP patients with 44 controls: 64% and 45% received continuous RRT (CRRT) (p = 0.07), with comparable rates of heart failure (24% versus 25%), ICU care (67% versus 70%), RRT successfully weaned (71% versus 75%), respectively; corresponding mortality rates were 24% and 32% (p = 0.44), hospital days of 205 (197-213) and 223 (215-232) per 1000 patient-days alive over one year (p = 0.002); with comparable RRT and catheter days. Serial serum creatinine in months following RRT cessation were comparable between either survivor-group. On multivariate analysis, heart failure or having received CRRT independently predicted mortality and longer hospital days (p < 0.05); ATCP was independently associated with reduced hospital days (p < 0.001). 17 ATCP patients and 14 controls required outpatient RRT weaning, with catheter days of 607 (568-648) and 683 (638-731) per 1000 patient-days in initial 90 days, respectively (p = 0.01).

CONCLUSIONS

Implementing a structured care pathway in patients with AKI-RRT may help reduce hospitalization, and reduce haemodialysis catheter days in the subgroup for outpatient RRT weaning.