TruGraf v1 is a laboratory-developed DNA microarray-based gene expression blood test to enable proactive noninvasive serial assessment of kidney transplant recipients with stable renal function. It has been previously validated in patients identified as Transplant eXcellence (TX: stable serum creatinine, normal biopsy results, indicative of immune quiescence), and not-TX (renal dysfunction and/or rejection on biopsy results). TruGraf v1 is intended for use in subjects with stable renal function to measure the immune status as an alternative to invasive, expensive, and risky surveillance biopsies. Materials and Methods. In this study, simultaneous blood tests and clinical assessments were performed in 192 patients from 7 transplant centers to evaluate TruGraf v1. The molecular testing laboratory was blinded to renal function and biopsy results. Results. Overall, TruGraf v1 accuracy (concordance between TruGraf v1 result and clinical and/or histologic assessment) was 74% (142/192), and a result of TX was accurate in 116 of 125 (93%). The negative predictive value for TruGraf v1 was 90%, with a sensitivity 74% and specificity of 73%. Results did not significantly differ in patients with a biopsy-confirmed diagnosis vs those without a biopsy. Conclusions. TruGraf v1 can potentially support a clinical decision enabling unnecessary surveillance biopsies with high confidence, making it an invaluable addition to the transplant physician's tool kit for managing patients. TruGraf v1 testing can potentially avoid painful and risky invasive biopsies, reduce health care costs, and enable frequent assessment of patients with stable renal function to confirm the presence of immune quiescence in the peripheral blood.

Kidney transplantation is the optimal treatment for many patients with end-stage kidney disease. The short-term outcomes of kidney transplantation have improved in the past few decades as a result of development of newer immunosuppressive drugs, more effective anti-microbial prophylaxis, and improved surgical techniques; however, long-term outcomes remain suboptimal. Routine posttransplant monitoring consists of the measurement of serum creatinine (SCr) and immunosuppressive drug levels. However, both are insensitive and non-specific markers of graft damage.

BACKGROUND:TruGraf v1 is a well-validated DNA microarray-based test that analyzes blood gene expression profiles as an indicator of immune status in kidney transplant recipients with stable renal function.METHODS:In this study, investigators assessed clinical utility of the TruGraf test in patient management. In a retrospective study, simultaneous blood tests and clinical assessments were performed in 192 patients at 7 transplant centers, and in a prospective observational study they were performed in 45 subjects at 5 transplant centers.RESULTS:When queried regarding whether or not the TruGraf test result impacted their decision regarding patient management, in 168 of 192 (87.5%) cases the investigator responded affirmatively. The prospective study indicated that TruGraf results supported physicians' decisions on patient management 87% (39/45) of the time, and in 93% of cases physicians indicated that they would use serial TruGraf testing in future patient management. A total of 21 of 39 (54%) reported results confirmed their decision that no intervention was needed, and 17 of 39 (44%) reported that results specifically informed them that a decision not to perform a surveillance biopsy was correct.CONCLUSIONS:TruGraf is the first and only noninvasive test to be evaluated for clinical utility in determining rejection status of patients with stable renal function and shows promise of providing support for clinical decisions to avoid unnecessary surveillance biopsies with a high degree of confidence. TruGraf is an invaluable addition to the transplant physician's tool kit for managing patient health by avoiding painful and invasive biopsies, reducing health care costs, and enabling frequent assessment of patients with stable renal function to confirm immune quiescence.

We performed orthogonal technology comparisons of concurrent peripheral blood and biopsy tissue samples from 69 kidney transplant recipients who underwent comprehensive algorithm-driven clinical phenotyping. The sample cohort included patients with normal protocol biopsies and stable transplant (sTx) function (n = 25), subclinical acute rejection (subAR, n = 23), and clinical acute rejection (cAR, n = 21). Comparisons between microarray and RNA sequencing (RNA-seq) signatures were performed and demonstrated a strong correlation between the blood and tissue compartments for both technology platforms. A number of shared differentially expressed genes and pathways between subAR and cAR in both platforms strongly suggest that these two clinical phenotypes form a continuum of alloimmune activation. SubAR is associated with fewer or less expressed genes than cAR in blood, whereas in biopsy tissues, this clinical phenotype demonstrates a more robust molecular signature for both platforms. The discovery work done in this study confirms a clear ability to detect gene expression profiles for sTx, subAR, and cAR in both blood and biopsy tissue, yielding equivalent predictive performance that is agnostic to both technology and platform. Our data also provide strong biological insights into the molecular mechanisms underlying these signatures, underscoring their logistical potential as molecular diagnostics to improve clinical outcomes following kidney transplantation.

Context: The TruGraf test is a blood-based assay that provides non-invasive, accurate assessment of adequacy of immunosuppression in kidney transplant recipients. TruGraf relies on gene-expression “signatures” that differentiate a state of Transplant eXcellence (TX, indicating adequately immunosuppressed) from not-TX. Objective: To evaluate the performance of the TruGraf test. Design: Analytical performance studies to characterize stability of RNA in blood during collection and shipment, analytical sensitivity (input RNA concentration), analytical specificity (interfering substances) and assay performance (clinical validity, and intra-assay, inter-assay, inter-laboratory reproducibility). Results: Total RNA extracted from whole blood specimens collected in PAXgene Blood RNA tubes was stable up to 3 days at room temperature (stable RNA yield). Under routine ambient shipping conditions, storage and shipping temperatures did not affect results. However, specimen shipments exposed to temperatures >400°C or to ambient temperatures for >3 days were unacceptable for processing. Analytical sensitivity studies demonstrated tolerance to variation in RNA input (50 to 400 ng per 3’ IVT (in vitro transcript] labeling reaction). Specificity studies using genomic DNA spiked into 3 ’IVT reactions at 10-20% demonstrated negligible assay interference. The test was reproducible across operators, runs, reagent lots, and laboratories. External validation demonstrated that the TruGraf blood test accurately classified patients in 72% of 295 samples. Conclusions: Analytical sensitivity, analytical specificity, robustness, quality control, and clinical validity of the TruGraf blood test were successfully verified, indicating its suitability for clinical use.

Background: Significant challenges exist to detecting kidney injury early in patients with kidney transplants. The current standard of care includes monitoring serum creatinine levels and immunosuppressive drug levels, both of which are poor early predictors of kidney graft damage. Protocol (surveillance) biopsies provide an accurate assessment of the transplanted kidney but are expensive, invasive, risking infection and bleeding and even graft loss, such that they are unsuited for frequent monitoring. Objectives: An economic analysis was performed to assess the economic impact of replacing protocol biopsies with blood molecular gene profiling in kidney transplant recipients. Methods: For the economic analysis, we utilized CMS fee schedule data, actual patient billing examples and published literature to estimate the per-patient tested savings of replacing protocol biopsies with the TruGraf blood test to monitor kidney transplant recipients. Results: The TruGraf test provides a net savings of $1,302 per patient per year, including the TruGraf test costs. In 2016, 19,060 kidney transplants were performed; replacing protocol biopsies with TruGraf testing could save $24.8 million in direct treatment costs per year. Conclusions: Use of the TruGraf blood test could spare patients unnecessary protocol biopsies. The healthcare system will realize significant economic benefits; in addition, the ability to intervene early with therapies to fend off clinical acute rejection may provide the added benefit of improving long term outcomes.

Background: TruGraf is a blood test that measures gene expression signatures in kidney transplant recipients, providing information on adequacy of immunosuppression. Signatures derived from peripheral blood using DNA microarrays have been internally and externally validated in two populations of transplant recipients: (i) patients designated as TX (“Transplant eXcellence”) - stable serum creatinine and normal biopsy, indicative of immune quiescence, and (ii) patients designated as not-TX (renal dysfunction and/or histological abnormalities). The test is intended for use in subjects with stable renal function as an alternative to protocol biopsies. Methodology: Simultaneous blood tests and transplant biopsies were performed in 169 patients. The molecular laboratory was blinded to renal function and biopsy results. Results: Biopsy-confirmed clinical phenotype was TX (105 cases), not-TX (64). Renal function was stable in 125 subjects (105 TX, 20 not-TX). Positive predictive value of TruGraf for detecting TX was 86% and 105/125 (84%) had a normal biopsy result. Significance of study: In subjects with stable renal function, TruGraf blood test result of TX corresponded to biopsy findings in 88% of cases. Results indicate that had the blood test been run in place of surveillance biopsies, 107/125 (86%) of patients with stable renal function may have avoided an invasive biopsy and 92/105 (88%) of these patients with biopsy-confirmed TX may have avoided a biopsy for a negative result.

BACKGROUND:Hypomagnesemia with urinary magnesium wasting is a well described adverse event with calcineurin inhibitor therapy. Prostate cancer is the most prevalent cancer in men in the United States. Injury to the cavernous nerves during radical prostatectomy frequently results in erectile dysfunction. Tacrolimus has been shown to be neuroprotective in the rat cavernous nerve injury model, an animal model representative of the neural injury that occurs in humans at the time of radical prostatectomy.METHODS:In a randomized, double-blind, placebo-controlled trial, the utility of tacrolimus was assessed for prevention of erectile dysfunction following bilateral nerve-sparing radical prostatectomy.RESULTS:Low dose tacrolimus, associated with low trough levels, resulted in mild hypomagnesemia, which was an early and persistent finding. As early as one week after institution of therapy, mean and median serum magnesium levels were significantly lower in the tacrolimus arm as compared to the placebo arm (p<0.001 for both). While the mean and median levels were within the normal range at Week 1, 10.9% of tacrolimus-treated patients had levels <1.8mg/dL, compared to none in the placebo arm (p=0.017). Median and mean levels remained significantly different at Week 5, Month 3 and Month 6. No clinical manifestations of hypomagnesemia were noted and no subject required treatment with magnesium. Changes in serum magnesium occurred earlier than other potential metabolic adverse events described with tacrolimus (changes in serum glucose, creatinine or potassium).CONCLUSIONS:These data indicate that mild hypomagnesemia is an early and sensitive biomarker for the effect of tacrolimus on the kidney.

Memory T cells play a central role in mediating allograft rejection and are a rational target for immunosuppressive therapy. Alefacept is a recombinant LFA3/IgG1 fusion protein that reduces the number of memory T cells in both psoriatic lesions and the peripheral circulation of psoriasis patients. This study evaluated the efficacy and safety of alefacept compared with placebo when combined with tacrolimus, mycophenolate mofetil and corticosteroids in de novo renal transplant recipients. Between December 2007 and March 2009 patients were randomized in a double-blind fashion to receive alefacept (n = 105) or placebo (n = 107) for 3 months and were then followed for a further 3 months. The primary efficacy endpoint was the incidence of biopsy-confirmed acute T cell mediated rejection (Banff grade ≥1) through Month 6. Memory T cell counts were significantly reduced in the alefacept group from Week 3 to study end compared with placebo. However, there was no significant difference between the alefacept and placebo groups for the primary efficacy endpoint (alefacept, 11.0% vs. placebo, 7.0%, p = 0.3). Patient and graft survival as well as renal function was similar between treatment groups. Safety and tolerability were generally similar between the treatment arms. Malignancy was higher in the alefacept treatment arm.

This first-in-human, phase I study evaluated the safety, tolerability, pharmacokinetic and pharmacodynamic profile of ASKP1240 in healthy subjects. Twelve sequential groups (each 6 active and 3 placebo) were randomly assigned to placebo or single ascending doses of intravenous ASKP1240 (0.00003-10 mg/kg). ASKP1240 exhibited nonlinear pharmacokinetics, with mean maximal serum concentrations and area under the serum concentration-time curves ranging from 0.7 to 251.6 μg/mL and 6.5 to 55409.6 h·μg/mL following doses 0.1 mg/kg-10 mg/kg, respectively. CD40 receptor occupancy by ASKP1240, which was dose-dependent, reached a maximum at doses above 0.01 mg/kg. ASKP1240 was well tolerated, with no evidence of cytokine release syndrome or thromboembolic events. Treatment emergent antibodies to ASKP1240 were detected in 5/70 (7.1%) ASKP1240 recipients. In conclusion, antagonism of the CD40/CD154 interaction with ASKP1240 was safe and well tolerated at the doses tested.

Purpose: Primary objective was to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of ASKP1240, a fully human anti-CD40 monoclonal antibody, when administered with standard immunosuppression to subjects who receive a de novo kidney transplant. Study Design: This is a randomized, double-blind, placebo controlled, parallel group study. Subjects were >= 18 but < = 65 years and of either gender receiving a first or repeat transplant from a living or deceased donor in the US. Subjects received intravenously (IV) a single dose of one of four ASKP1240 dose levels (50 mg, 100 mg, 200 mg, 500 mg) or placebo. After dosing, subjects were followed to Study Day 90. Patients received standard (by center) maintenance immunosuppression post-transplant except antibody induction therapy was prohibited. Results: Fifty subjects were randomized with 46 receiving study drug. One subject on ASKP1240 50 mg did not complete the last study visit. Treatment groups were numerically similar with regard baseline characteristics except there were no females in the ASKP1240 50 mg group. Cmax of ASKP1240 increased linearly with increasing dose, while AUC showed more than dose proportional increase in the range of 50 mg to 500 mg. The maximal receptor occupancy for B cell CD40 was reached at all dose levels however the duration of receptor occupancy tended to increase as dose increased. No subjects experienced cytokine release syndrome or thromboembolic event. Treatment emergent anti-ASKP1240 antibodies were seen only in 1 (11.1%) subject in the ASKP1240 50 mg group and was detected at Study Day 7 only. There were no deaths or graft losses in the study. Other key outcomes at Day 90 are shown in the table below.Table: [Key Outcomes at Day 90]Conclusions: ASKP1240 was well tolerated at all doses with no evidence of cytokine release cyndrome or thromboembolic event. Incidence of infection was not dose dependent. ASKP1240 showed non-linear pharmacokinetics. The B cell CD40 receptor occupancy tended to be prolonged as dose increased.