Citations

Parkinson’s disease (PD) is generally considered a sporadic disorder, but a strong genetic background is often found. The aim of this study was to identify the underlying genetic cause of PD in two affected siblings and to subsequently assess the role of mutations in Cathepsin B (CTSB) in susceptibility to PD. A typical PD family was identified and whole-exome sequencing was performed in two affected siblings. Variants of interest were validated using Sanger sequencing. CTSB p.Gly284Val was genotyped in 2077 PD patients and 615 unrelated healthy controls from the Czech Republic, Ireland, Poland, Ukraine, and the USA. The gene burden analysis was conducted for the CTSB gene in an additional 769 PD probands from Mayo Clinic Florida familial PD cohort. CTSB expression and activity in patient-derived fibroblasts and controls were evaluated by qRT-PCR, western blot, immunocytochemistry, and enzymatic assay. The CTSB p.Gly284Val candidate variant was only identified in affected family members. Functional analysis of CTSB patient-derived fibroblasts under basal conditions did not reveal overt changes in endogenous expression, subcellular localization, or enzymatic activity in the heterozygous carrier of the CTSB variant. The identification of the CTSB p.Gly284Val may support the hypothesis that the CTSB locus harbors variants with differing penetrance that can determine the disease risk.

10581 Background: MSI-H colorectal cancer is most often a result of deleterious mutations in mismatch repair genes, but can also occur through repressed gene transcription due to hypermethylation of the MLH1 promoter, often associated with BRAF V600E mutations. However, there is a subset of patients who have a “constitutional epimutation”, resulting in hypermethylation of MLH1 throughout normal tissue. We observed a young patient develop a second primary Lynch associated malignancy (see Table 1) who was found to have a constitutional epimutation in MLH1 that prompted us to review the frequency with which the test was ordered and the positivity rate, as well as outline the clinical history in the positive cases. Methods: We reviewed all of the testing ordered for MLH1 hypermethylation of peripheral blood (MLHPB) at the Mayo Clinic Laboratory between 09/01/2020 and 09/01/2021. To the best of our knowledge, this is the only clinically available testing lab in the United States. We reviewed positive casesfor characteristics including the number of malignancies, age of diagnosis, and family history. Results: 33 MLHPB total tests were ordered in the United States at the Mayo Clinic laboratories between 09/01/2020 and 09/01/2021. Three of the tests were positive, including the single test ordered by our institution, and one of the two additional positive tests was available for detailed review. Our institution’s positive test case was a 41 year old women who developed T4N2M0 colorectal cancer 5 years after being treated for endometrial cancer. She had endometrial cancer with absence of MLH1 and PMS2 staining and had a negative germline cancer risk panel at age 36. Five years later, she developed a T4N2 colorectal cancer after which repeat germline testing with RNA sequencing was negative and she was found to have constitutional MLH1 promoter hypermethylation. We were able to obtain clinical information about two of the three individuals with positive tests (See Table). Conclusions: Recognition of constitutional MLH1 hypermethylation may allow for earlier recognition of Lynch related malignancies in affected patients and families. Testing appears infrequent and this condition often goes unrecognized. Specific consensus guidelines may improve recognition and cancer screening in this population. [Table: see text]

e19553 Background: The combination of tafa + LEN has accelerated approval in the United States (2020) and conditional approval in Canada and Europe (2021) for R/R DLBCL in ASCT-ineligible adult pts. A tolerable safety profile for R-CHOP + tafa ± LEN in pts with newly diagnosed DLBCL in the Phase Ib First-MIND study (NCT04134936) was previously reported, with numerically superior efficacy for R-CHOP + tafa + LEN (ASH 2021; #3556). We report PK, PD, and immunogenicity of R-CHOP + tafa ± LEN in this first line setting. Methods: Eligible pts ≥18 years with treatment-naïve DLBCL, IPI 2–5, and ECOG PS 0–2 were randomized 1:1 to either six 21-day (D) cycles (C) of R-CHOP (R-CHO, D1; P, D1–5) + tafa (12 mg/kg IV, D1, 8, 15) (Arm A) or R-CHOP + tafa + LEN (25 mg orally, D1–10) (Arm B). Secondary endpoints included tafa serum conc and number and percentage of pts developing anti-tafa Abs. Exploratory endpoints included natural killer (NK) cell, T-cell, and B-cell count in peripheral blood. Results: Data cut-off: 13 March 2021 for safety analysis, incl. ≥1 month follow-up after EoT visit for all pts; 15 September 2021 for efficacy. Tafa serum conc reached steady state by C3 (geometric mean trough conc: Arm A, 186.40–216.55 µg/mL; Arm B, 171.77–201.54 µg/mL) and steadily declined after treatment completion. Anti-tafa Abs were detected in 1/65 (1.5%) pts. This pt showed pre-existing tafa Abs at baseline, which decreased during treatment. Median NK cell count decreased from baseline at C1D8 but was at baseline or higher levels by EoT visit (Arm A) and C1D15 (Arm B; Table). T-cell count decreased from baseline at C1D8 in both arms but was at baseline level or higher by C1D15 (Arm A) and EoT visit (Arm B). Median B-cell count decreased from baseline to 0 cells/μL (Arm A, C1D15; Arm B, C1D8); at 6-month follow-up after EoT visit, B-cell count had recovered to measurable levels in ̃50% of pts. Conclusions: Tafa serum conc reached and maintained a therapeutic dose level in this first-line regimen and declined in line with known tafa half-life (̃16 days) after treatment completion; tafa levels were comparable between the two treatment arms. No pt developed treatment-induced or treatment-boosted anti-tafa Abs. Median NK-cell, T-cell, and B-cell counts were comparable between treatment arms in all cycles. Clinical trial information: NCT04134936. [Table: see text]

TPS7590 Background: Up to 40% of patients relapse or are refractory (R/R) to R-CHOP, the current standard of care for diffuse large B-cell lymphoma (DLBCL), indicating an unmet need, particularly in patients with high-intermediate and high-risk disease (IPI 3–5). POLARIX (NCT03274492) evaluated a modified regimen substituting polatuzumab vedotin for vincristine (pola-R-CHP), demonstrating modest improvement in PFS with no OS benefit between treatment arms. The addition of lenalidomide (LEN) to R-CHOP improved both PFS and OS in the ECOG-ACRIN E1412 trial but not in the Phase III ROBUST study, in which a lower dose of LEN was used, despite a positive trend toward 2-year PFS in a subgroup analysis. The chemo-free immunotherapy tafasitamab + LEN has received accelerated approval in the United States (2020), and conditional marketing authorization in Europe and Canada (2021) in adult patients with R/R DLBCL ineligible for ASCT based on L-MIND (NCT02399085). The primary analysis of First-MIND (NCT04134936), a Phase Ib randomized safety study of R-CHOP + tafasitamab ± LEN in patients with previously untreated and newly diagnosed DLBCL, demonstrated that adding tafasitamab + LEN does not impair dosing and scheduling of R-CHOP, with toxicities similar to those expected with R-CHOP alone (ASH 2021; #3556). frontMIND (NCT04824092) will investigate the efficacy and safety of R-CHOP + tafasitamab + LEN vs R-CHOP alone in previously untreated patients with high-intermediate and high-risk DLBCL. Methods: frontMIND is a Phase III, multicenter, randomized, double-blind, placebo-controlled study. Approximately 880 patients are planned to be randomized at ̃350 centers in North and South America, Europe, and Asia-Pacific. Eligible patients aged 18‒80 years with previously untreated local biopsy-proven, CD20+ DLBCL with IPI score 3–5 (age-adjusted IPI 2–3 if ≤60 years), and ECOG PS 0–2 will be enrolled. Patients with transformed lymphoma (except double or triple hit lymphoma) are excluded. Patients will be randomized 1:1 to receive six 21-day (D) cycles of either R-CHOP + tafasitamab (12 mg/kg intravenously, D 1, 8, and 15) + LEN (25 mg orally, D1–10) or R-CHOP + tafasitamab and LEN placebos. Patients will be followed for up to 5 years after the end of treatment. The primary endpoint is investigator-assessed PFS. Secondary endpoints include investigator-assessed event-free survival, OS, safety, and tafasitamab serum concentration (trough and Cmax levels). Sensitivity and specificity of minimal residual disease for early detection of disease progression is an exploratory endpoint; further MRD parameters may also be investigated. The study is funded by MorphoSys AG and conducted with the scientific support of members of the Fondazione Italiana Linfomi and the German Lymphoma Alliance. Clinical trial information: NCT04824092.

3084 Background: Homologous recombination (HR) is an essential, high-fidelity mechanism to repair DNA double strand breaks (DSBs) in cancer cells. CYT-0851 inhibits HR leading to an accumulation of unrepaired DSBs and tumor cell death. We are reporting the completed Phase 1 dose-escalation results and RP2D selection to support ongoing development of CYT-0851. Methods: Patients (pts) with advanced hematologic and solid tumors were treated with continuous 28-day cycles of increasing doses of CYT-0851 following a 3+3 design. The primary objective was determining the maximum tolerated dose. Secondary objectives included safety, pharmacokinetics, and anti-tumor activity. Results: As of a 15 Nov 2021 data cutoff (DCO), 73 pts with advanced cancers (NHL n = 18; Sarcoma n = 16; Pancreas n = 11; Breast n = 8; HNSCC n = 6; Ovarian n = 4; SCLC n = 4; Other n = 4; Myeloma n = 2) were treated in 12 cohorts (total daily doses: 30 mg to 1200 mg). One pt experienced a dose-limiting toxicity (DLT) of reversible metabolic acidosis at 1200 mg. Two of 3 pts at 800 mg experienced reversible DLT-like events in Cycle 2 of Gr3 dry skin and Gr3 myalgia and polyarthritis, respectively. Three of 10 pts treated at 600 mg experienced DLT-like events in Cycle 1: 1 pt experienced an SAE of Gr3 anorexia with Gr3 stomatitis, vomiting, and dehydration and 2 pts had Gr3 fatigue. No DLTs occurred at 400 mg daily which was selected as the RP2D. 42 pts (57.5%) experienced a CYT-0851-related adverse event (AE), including 12 (16.4%) with a Gr3/4 AE. There were no treatment-related deaths. AE leading to CYT-0851 withdrawal were reported in 2 pts (2.7%) treated with 600 and 800 mg. The most common CYT-0851-related AEs were primarily Gr1/2 and included fatigue (20.5%), hyperuricemia (11%), nausea (11%), alopecia (9.6%), constipation (8.2%) and headache (8.2%). CYT-0851 exposure was approximately dose-proportional across the evaluated doses with an effective half-life of ̃3 days. Exposure at 400 mg daily was consistent with efficacy in preclinical models. 46 pts were evaluable for response at the DCO. 12 pts with NHL were evaluable by Lugano and included 1 CR in FL and 1 PR in DLBCL treated for 393+ and 244 days respectively. 34 pts with solid tumors were evaluable by RECIST v1.1 with 1 PR in a pt with myxofibrosarcoma treated for 313 days and 16 pts with stable disease. Fifteen pts were treated for 100+ days and 5 for 180+ days. Conclusions: CYT-0851 has demonstrated promising and broad clinical activity in a Ph 1 population of pts with advanced cancers. The safety profile is favorable as characterized by events that were infrequent, primarily Gr1/2, and reversible. Six expansion cohorts (DLBCL, Follicular Lymphoma, Myeloma, Pancreatic, Ovarian and Sarcoma) are enrolling to characterize activity at the RP2D. Ph 1 evaluation of CYT-0851 in combination with 3 chemotherapy backbones is also ongoing. Clinical trial information: NCT03997968.

Hodgkin lymphoma (HL) is an uncommon malignancy of B-cell origin. Classical HL (cHL) and nodular lymphocyte–predominant HL are the 2 main types of HL. The cure rates for HL have increased so markedly with the advent of modern treatment options that overriding treatment considerations often relate to long-term toxicity. These NCCN Guidelines Insights discuss the recent updates to the NCCN Guidelines for HL focusing on (1) radiation therapy dose constraints in the management of patients with HL, and (2) the management of advanced-stage and relapsed or refractory cHL.

Adverse childhood experiences (ACEs) are potentially traumatic events that can cause lifelong suffering, with 1 out of 2 children in the United States experiencing at least 1 ACEs. The intergenerational effect of ACEs has been described, but there’s still paucity of knowledge of its impact on child development and behavior in children enrolled in Early Head Start (EHS) home visiting programs. A retrospective observational study was performed with 71 parents and 92 children participating in the EHS Home Visiting Program in Olmsted County from 2014 to 2019. Parents reported their own ACEs using a 10-item questionnaire. Children’s social-emotional status was evaluated with Devereux Early Childhood Assessment Second Edition (DECA) and development was evaluated using the Brigance Early Childhood Screens III. Referrals of children by EHS staff to community agencies were recorded. The association between parental ACEs score, developmental outcomes and referrals was analyzed. Parental ACEs score of 4 or more was associated with failing at least 1 domain on the Brigance screen ( P = .02) especially adaptive/cognitive domain ( P = .05), and increased risk of referral to community resources ( P < .001). However, there was no association between ACEs scores and failing DECA screens. We identified an intergenerational association between parental exposure to ACEs and risk for childhood developmental delay and referrals to community services. Parental adverse childhood experiences (ACEs) have intergenerational effects on offspring. In our study, parental ACEs are associated with offspring developmental delays and referral to community resources. Screening for parental adverse childhood experiences, a key social determinant of health, is imperative and should be incorporated into primary care and early childhood settings to identify children at risk for developmental delay.