Podocyte density is reduced in kidney allografts with high‐risk APOL1 genotypes at transplantation

Variants in apolipoprotein L1 (APOL1) gene are associated with nondiabetic kidney diseases in black subjects and reduced kidney transplant graft survival. Living and deceased black kidney donors (n = 107) were genotyped for APOL1 variants. To determine whether allografts from high‐risk APOL1 donors have reduced podocyte densities contributing to allograft failure, we morphometrically estimated podocyte number, glomerular volume, and podocyte density. We compared allograft loss and eGFR trajectories stratified by APOL1 high‐risk and low‐risk genotypes. Demographic characteristics were similar in high‐risk (n = 16) and low‐risk (n = 91) donors. Podocyte density was significantly lower in high‐risk than low‐risk donors (108 ± 26 vs 127 ± 40 podocytes/106um3, P = .03). Kaplan‐Meier graft survival (high‐risk 61% vs. low‐risk 91%, p‐value = 0.049) and multivariable Cox models (hazard ratio = 2.6; 95% CI, 0.9‐7.8) revealed higher graft loss in recipients of APOL1 high‐risk allografts over 48 months. More rapid eGFR decline was seen in recipients of high‐risk APOL1 allografts (P < .001). At 60 months, eGFR was 27 vs. 51 mL/min/1.73 min2 in recipients of APOL1 high‐risk vs low‐risk kidney allografts, respectively. Kidneys from high‐risk APOL1 donors had worse outcomes versus low‐risk APOL1 genotypes. Lower podocyte density in kidneys from high‐risk APOL1 donors may increase susceptibility to CKD from subsequent stresses in both the recipients and donors

Pediatric and adult H3 K27M-mutant diffuse midline glioma treated with the selective DRD2 antagonist ONC201

BACKGROUND: H3 K27M-mutant diffuse midline glioma is a fatal malignancy with no proven medical therapies. The entity predominantly occurs in children and young adults. ONC201 is a small molecule selective antagonist of dopamine receptor D2/3 (DRD2/3) with an exceptional safety profile. Following up on a durable response in the first H3 K27M-mutant diffuse midline glioma patient who received ONC201 (NCT02525692), an expanded access program was initiated. METHODS: Patients with H3 K27M-mutant gliomas who received at least prior radiation were eligible. Patients with leptomeningeal spread were excluded. All patients received open-label ONC201 orally once every week. Safety, radiographic assessments, and overall survival were regularly assessed at least every 8 weeks by investigators. As of August 2018, a total of 18 patients with H3 K27M-mutant diffuse midline glioma or DIPG were enrolled to single patient expanded access ONC201 protocols. Among the 18 patients: seven adult (\u3e 20 years old) and seven pediatric (\u3c 20 years old) patients initiated ONC201 with recurrent disease and four pediatric patients initiated ONC201 following radiation, but prior to disease recurrence. FINDINGS: Among the 14 patients with recurrent disease prior to initiation of ONC201, median progression-free survival is 14 weeks and median overall survival is 17 weeks. Three adults among the 14 recurrent patients remain on treatment progression-free with a median follow up of 49.6 (range 41-76.1) weeks. Among the 4 pediatric patients who initiated adjuvant ONC201 following radiation, two DIPG patients remain progression-free for at least 53 and 81 weeks. Radiographic regressions, including a complete response, were reported by investigators in a subset of patients with thalamic and pontine gliomas, along with improvements in disease-associated neurological symptoms. INTERPRETATION: The clinical outcomes and radiographic responses in these patients provide the preliminary, and initial clinical proof-of-concept for targeting H3 K27M-mutant diffuse midline glioma with ONC201, regardless of age or location, providing rationale for robust clinical testing of the agent