Leucovorin Research Articles

Active congenital toxoplasmosis, an underestimated threat: case report

Congenital toxoplasmosis (CT) is a consequence of vertical transmission of the toxoplasma gondii parasite during gestation. We present a case of premature CT, adolescent mother diagnosed in the second trimester of pregnancy with gestational toxoplasmosis, without treatment. After birth, the patient was admitted to the neonatal intermediate unit, with normal vital signs, on physical examination with mild signs of shortness of breath, splenomegaly approximately 7cm, hepatomegaly 3 cm, generalized micropapular lesions, chest X-ray without alteration and positive IgG and IgM serologies, confirming a severe CT diagnosis due to ocular, cerebral, hematologic and skin involvement; she received pyrimethamine, sulfadiazine, folinic acid and prednisolone. The appearance of these cases of severe component sets off alarms in prioritizing maternal and family education and also human talent at the time of approaching and monitoring the pregnant woman, contributing substantially to the decrease in vertical transmission, and in turn the long-term impact on the newborn and her family.

Synergistic Effect of Lenvatinib and Chemotherapy in Hepatocellular Carcinoma Using Preclinical Models.

The current study aimed to evaluate the synergistic efficacy of lenvatinib and FOLFOX (infusional fluorouracil (FU), folinic acid, and oxaliplatin) in hepatocellular carcinoma (HCC) using patient-derived xenograft (PDX) and PDX-derived organotypic spheroid (XDOTS) models in vivo and in vitro. PDX and matched XDOTS models originating from three patients with HCC were established. All models were divided into four groups and treated with drugs alone or in combination. Tumor growth in the PDX models was measured and recorded, and angiogenesis and phosphorylation of the vascular endothelial growth factor receptor (VEGFR2), rearranged during transfection (RET), and extracellular signal-regulated kinase (ERK) were detected using immunohistochemistry and Western blot assays. The proliferative ability of XDOTS was evaluated through active staining and immunofluorescence staining, and the effect of the combined medication was evaluated using the Celltiter-Glo luminescent cell viability assay. Three PDX models with genetic characteristics similar to those of the original tumors were successfully established. Combining lenvatinib with FOLFOX led to a higher tumor growth inhibition rate than individual therapies (P < 0.01). Immunohistochemical analysis demonstrated that the combined treatment significantly inhibited the proliferation and angiogenesis of PDX tissues (P < 0.05), and Western blot analysis showed that the combined treatment significantly inhibited the phosphorylation of VEGFR2, RET, and ERK compared with single-agent treatment. Additionally, all three matched XDOTS models were successfully cultured with satisfactory activity and proliferation, and the combined therapies led to better suppression of XDOTS growth compared with individual therapy (P < 0.05). Lenvatinib combined with FOLFOX had a synergistic antitumor effect in HCC PDX and XDOTS models by inhibiting the phosphorylation of VEGFR, RET, and ERK.

Reanalysis of exome sequencing data reveals a treatable neurometabolic origin in two previously undiagnosed siblings with neurodevelopmental disorder.

Neurodevelopmental disorders (NDDs) have broad heterogeneity both clinically and genetically. Inborn errors of metabolism can be one of the reasons of neurodevelopmental disruption causing specific NDDs. Although there is tremendous advance in molecular identification via next-generation sequencing (NGS), there are still many unsolved patients with NDD. Reanalysis of NGS data with different pipelines can at least partially accomplish this challenge. Herein, we report clinic and genetic components of an adult sib-pair with an undiagnosed NDD condition, which has been solved through reanalysis of whole-exome sequencing (WES). Parallel analysis of SNP-based genotyping and WES was performed to focus on variants only in loci with positive logarithm of the odds scores. WES data was analyzed through three different pipelines with two distinct bed files. Reanalysis of WES data led us to detect a homozygous FOLR1 variant (ENST00000393676.5:c.610C > T, p.(Arg204Ter), rs952165627) in the affected sib-pair. Surprisingly, the variant could not be detected in the first analysis as the variant region is not included in the first bed file which mayfrequently beused. Biochemical tests of CSF have confirmed the genetic analysis, CSF folic acid levels were detected low in sib-pair, and intravenous folinic acid treatment improved the disease course for the first 6 months of follow-up even at late diagnosis age. Although combined analysis of SNP-based genotyping and WES is a powerful tool to reveal the genetic components of heterogeneous diseases, reanalysis of genome data still should be considered in unsolved patients. Also, biochemical screening helps us to decipher undiagnosed NDD that may be a treatable neurometabolic condition.

Methotrexate Drug Monitoring From Central Access: Can Blood Sample Collection From Central Venous Access Replace Peripheral Venipuncture in Adults?

Intravenous high-dose methotrexate (MTX ≥ 1 g/m 2 ) is frequently used in patients with cerebral lymphoma or other malignancies. In addition to its potent efficacy, it is known to have pronounced toxicity and life-threatening side effects. Regular-level monitoring at short and defined intervals is mandatory. This study aimed to evaluate the possibility of replacing peripheral blood sampling with blood samples from central venous catheters for therapeutic monitoring of MTX in adults. A total of 6 patients and 7 cycles of chemotherapy (6 females; 5 with cerebral non-Hodgkin lymphoma and 1 with osteosarcoma, median age 51 years; range 33-62 years) were included. An immunoassay was used for quantitative analysis of MTX levels. The measurement points were obtained in the time intervals of 24, 42, 48, and 72 hours, and afterward, every 24 hours until the level was below <0.1 µmol/L. After flushing with 10 mL of saline solution and discarding 10 mL of venous blood, blood was drawn from the central venous access through which MTX had previously been administered. Simultaneously, MTX levels were obtained from peripheral venipuncture. Methotrexate levels from central venous access and MTX levels from peripheral venipuncture showed a significant correlation (r = 0.998; P < 0.01; n = 35). During withdrawal from the central access group, 17 values showed a lower MTX level, 10 showed a higher level, and 8 showed no difference. However, the MTX level difference was not significant ( P = 0.997, linear mixed model). No increase in the dose of calcium folinate was necessary based on the collected MTX levels. In adults, MTX monitoring from central venous access is not inferior to monitoring from peripheral venipuncture. Repeated venipuncture to measure MTX levels can be replaced after establishing standardized instructions for proper sampling by a central venous catheter.

Brain Uptake of Folate Forms in the Presence of Folate Receptor Alpha Antibodies in Young Rats: Folate and Antibody Distribution.

In a rat model, following exposure to rat folate receptor alpha antibodies (FRαAb) during gestation, FRαAb accumulates in the placenta and the fetus and blocks folate transport to the fetal brain and produces behavioral deficits in the offspring. These deficits could be prevented with folinic acid. Therefore, we sought to evaluate folate transport to the brain in young rat pups and determine what effect FRαAb has on this process, to better understand the folate receptor autoimmune disorder associated with cerebral folate deficiency (CFD) in autism spectrum disorders (ASD). When injected intraperitoneally (IP), FRαAb localizes to the choroid plexus and blood vessels including the capillaries throughout the brain parenchyma. Biotin-tagged folic acid shows distribution in the white matter tracts in the cerebrum and cerebellum. Since these antibodies can block folate transport to the brain, we orally administered various folate forms to identify the form that is better-absorbed and transported to the brain and is most effective in restoring cerebral folate status in the presence of FRαAb. The three forms of folate, namely folic acid, D,L-folinic acid and levofolinate, are converted to methylfolate while L-methylfolate is absorbed as such and all are efficiently distributed to the brain. However, significantly higher folate concentration is seen in the cerebrum and cerebellum with levofolinate in the presence or absence of FRαAb. Our results in the rat model support testing levofolinate to treat CFD in children with ASD.

Comparative Effectiveness of FOLFIRINOX Versus Gemcitabine and Nab-paclitaxel in Initially Unresectable Locally Advanced Pancreatic Cancer: A Population-based Study to Assess Subsequent Surgical Resection and Overall Survival

AimsFirst-line FOLFIRINOX (FOLinic acid, Fluorouracil, IRINotecan, and OXaliplatin) and gemcitabine plus nab-paclitaxel (GnP) have been publicly funded for patients with unresectable locally advanced pancreatic cancer (uLAPC) in Ontario, Canada. We examined the overall survival and surgical resection rate after first-line FOLFIRINOX or GnP and determined the association between resection and overall survival in patients with uLAPC. Materials and methodsWe conducted a retrospective population-based study including patients with uLAPC who received first-line treatment FOLFIRINOX or GnP from April 2015 to March 2019. The cohort was linked to administrative databases to ascertain demographic and clinical characteristics. Propensity score methods were used to balance differences between FOLFIRINOX and GnP. The Kaplan–Meier method was used to calculate overall survival. Cox regression was used to determine the association between receipt of treatment and overall survival, adjusting for time-dependent surgical resections. ResultsWe identified 723 patients with uLAPC (mean age = 65.8, 43.5% female) who received FOLFIRINOX (55.2%) or GnP (44.8%). The median overall survival and 1-year overall survival probability were higher for FOLFIRINOX (13.7 months, 54.6%) than for GnP (8.7 months, 34.0%). Post-chemotherapy surgical resection occurred in 89 (12.3%) patients (FOLFIRINOX: 74 [18.5%] versus GnP: 15 [4.6%]), with no difference in survival since surgery between FOLFIRINOX and GnP (P = 0.29). After adjusting time-dependent post-treatment surgical resection, FOLFIRINOX (inverse probability treatment weighting hazard ratio 0.72, 95% confidence interval 0.61, 0.84) was independently associated with improved overall survival. ConclusionsIn this real-world population-based study of patients with uLAPC, FOLFIRINOX was associated with improved survival and higher resection rates. FOLFIRINOX was associated with improved survival in patients with uLAPC after accounting for the effect of post-chemotherapy surgical resection, suggesting the benefit of FOLFIRINOX was not solely due to improving resectability.

Strategic use of levofolinic acid for methotrexate-induced side effects in juvenile idiopathic arthritis: a prospective observational study

ObjectiveTo evaluate the efficacy of levofolinic acid (LVF) administered 48 h before methotrexate (MTX) in reducing gastrointestinal side effects without interference with drug efficacy.MethodsA prospective observational study was performed including patients with Juvenile Idiopathic Arthritis (JIA) reporting significant gastrointestinal discomfort after MTX despite taking a dose of LVF 48 h after MTX. Patients with anticipatory symptoms were excluded. A LVF supplemental dose was added 48 h before MTX and patients were followed every 3–4 months. At each visit data on gastrointestinal symptoms, disease activity (JADAS, ESR, CRP values) and treatment changes were collected. Friedman test for repeated measures analyzed differences between these variables over time.ResultsTwenty-one patients were recruited and followed for at least 12 months. All patients received MTX subcutaneously (mean 9.54 mg/m2) and LVF 48 h before and after MTX (mean 6.5 mg/dose), 7 received a biological agent too. Complete remission of gastrointestinal side effects was reported in 61.9% of study patients at first visit (T1) and increased over time (85.7%, 95.2%, 85.7% and 100% at T2, T3, T4, T5, respectively). MTX efficacy was maintained as showed by significant reduction of JADAS and CRP (p = 0.006 and 0.008) from T1 to T4 and it was withdrawn for remission in 7/21.ConclusionsLVF given 48 h before MTX significantly reduced gastrointestinal side effects and did not reduce drug’s efficacy. Our results suggest that this strategy may improve compliance and quality of life in patients with JIA and other rheumatic diseases treated with MTX.

Tumor Regression Grade and Overall Survival following Gastrectomy with Preoperative Therapy for Gastric Cancer.

Pre-/perioperative chemotherapy is well-established for management of locoregional gastric cancer (LRGC). The American Joint Committee on Cancer advocates histopathologic assessment of tumor regression grade (TRG) but does not endorse a specific schema. We sought to examine the prognostic value of the recently revised National Comprehensive Cancer Network (NCCN) definition of TRG specifying TRG0 as no disease in primary tumor or lymph nodes. Patients with clinical-stage T2+/N+/M0 LRGC receiving preoperative chemotherapy and curative-intent gastrectomy were identified (2000-2020). TRG using the current NCCN definition was retrospectively assigned. Factors associated with TRG were examined using ordinal logistic regression and overall survival (OS) was assessed using the Kaplan-Meier method and Cox regression. Among 117 patients, the most common chemotherapy regimen was epirubicin, cisplatin, plus fluorouracil or capecitabine (ECF/ECX) (n = 48, 41%), followed by folinic acid, fluorouracil, and oxaliplatin (FOLFOX) (n = 30, 26%), and fluorouracil, leucovorin, oxaliplatin, plus docetaxel (FLOT) (n = 13, 11%). TRG3 was the most common histopathologic response (n = 68, 58%), followed by TRG2 (n = 25, 21%), TRG1 (n = 18, 15%), and, lastly, TRG0 (n = 6, 5.1%). The only preoperative factor independently associated with lower TRG was gastroesophageal junction tumor location (OR 0.24, p = 0.012). Higher TRG was independently associated with worse OS in a stepwise fashion (HR 1.49, p = 0.026). Posttreatment pathologic lymph node status was the strongest prognostic factor (HR 1.93, p = 0.026). Independent prognostic value of TRG and ypT stage could not be shown due to substantial overlap. TRG using the contemporary NCCN definition is associated with OS in LRGC. TRG0 is uncommon but with excellent prognosis. ypN status is the strongest prognostic factor and the revised NCCN definition acknowledging this is appropriate.

The Impact of Pre-Chemotherapy Body Composition and Immunonutritional Markers on Chemotherapy Adherence in Stage III Colorectal Cancer Patients

Patients with colorectal cancer (CRC) often fail to complete full-course chemotherapy with a standard dose due to various reasons. This study aimed to determine whether body composition affects chemotherapy adherence in patients with CRC. The medical records of 107 patients with stage III CRC who underwent adjuvant folinic acid, fluorouracil and oxaliplatin (FOLFOX) chemotherapy at a single center between 2014 and 2018 were analyzed retrospectively. Blood test results for selected immunonutritional markers were analyzed and body composition was measured through computed tomography. Univariate and multivariate analyses were performed on low and high relative dose intensity (RDI) groups, based on an RDI of 0.85. In the univariate analysis, a higher skeletal muscle index was correlated with a higher RDI (p = 0.020). Psoas muscle index was also higher in patients with high RDI than in those with low RDI (p = 0.026). Fat indices were independent of RDI. Multivariate analysis was performed for the aforementioned factors and results showed that age (p = 0.028), white blood cell count (p = 0.024), and skeletal muscle index (p = 0.025) affected RDI. In patients with stage III CRC treated with adjuvant FOLFOX chemotherapy, a decrease in RDI was related to age, white blood cell count, and skeletal muscle index. Therefore, if we adjust the drug dosage in consideration of these factors, we can expect an increased treatment efficiency in patients by increasing chemotherapy compliance.

Must folic acid and folinic acid be substituted in methotrexate treatment? If yes, how much?

Must folic acid and folinic acid be substituted in methotrexate treatment? If yes, how much?

Zolbetuximab + mFOLFOX6 as first-line (1L) treatment for patients (pts) withclaudin-18.2+ (CLDN18.2+) / HER2− locally advanced (LA) unresectable or metastatic gastric or gastroesophageal junction (mG/GEJ) adenocarcinoma: Primary results from phase 3 SPOTLIGHT study

LBA292 Background: 1L treatment for pts with HER2−, mG/GEJ adenocarcinoma is typically chemotherapy and immunotherapy; an unmet need still exists. CLDN18.2 is expressed in normal gastric mucosa cells and retained in mG/GEJ tumor cells. In the FAST study, zolbetuximab, which targets CLDN18.2, prolonged survival of pts with LA unresectable or mG/GEJ adenocarcinoma when combined with chemotherapy. SPOTLIGHT (NCT03504397) is a phase 3 global, double-blind study comparing zolbetuximab + folinic acid, 5-FU, and oxaliplatin (mFOLFOX6) vs placebo + mFOLFOX6 as 1L treatment for pts with CLDN18.2+/ HER2−, LA unresectable or mG/GEJ adenocarcinoma. Methods: Previously untreated pts with CLDN18.2+ (moderate-to-strong membrane staining in ≥75% tumor cells by IHC)/HER2− LA unresectable or mG/GEJ adenocarcinoma were randomized 1:1 to zolbetuximab IV 800 mg/m2 (cycle [C] 1, day [D] 1) followed by 600 mg/m2 (C1D22, and every 3 weeks in later cycles) + mFOLFOX6 IV (D1, 15, 29) for four 42-day cycles vs placebo + mFOLFOX6; pts without PD continued for &gt;4 cycles with zolbetuximab or placebo, + folinic acid and 5-FU at investigator’s discretion until PD or discontinuation criteria were met. The primary endpoint (EP) was PFS per RECIST v1.1 by IRC. Secondary EPs included OS, ORR, and safety. Differences in efficacy between treatment arms were tested by stratified log rank tests; OS was tested if PFS was significant. Results: Among 2735 pts screened, 565 pts were randomized 1:1 to zolbetuximab + mFOLFOX6 (N = 283) or placebo + mFOLFOX6 (N = 282). PFS was statistically significantly improved with zolbetuximab + mFOLFOX6 (median 10.61 vs 8.67 mo, HR 0.751, P=0.0066; Table). OS was also significantly improved (median 18.23 vs 15.54 mo, HR 0.750, P=0.0053, &lt; 0.0135 as boundary; Table). ORR was similar between treatment arms. Most common TEAEs with zolbetuximab + mFOLFOX6 were nausea (82.4% vs 60.8% in zolbetuximab vs placebo arms), vomiting (67.4% vs 35.6%), and decreased appetite (47.0% vs 33.5%); the incidences of serious TEAEs were similar between both arms (44.8% vs 43.5%). Conclusions: Targeting CLDN18.2 with 1L zolbetuximab combined with mFOLFOX6 statistically significantly prolonged PFS and OS in pts with CLDN18.2+/ HER2−, LA unresectable or mG/GEJ adenocarcinoma. TEAEs were consistent with previous studies. Zolbetuximab + mFOLFOX6 may be a new option for these pts. Funding source: This study was funded by Astellas Pharma Inc. Medical writing support, conducted in accordance with Good Publication Practice (GPP 2022) and the International Committee of Medical Journal Editors (ICMJE) guidelines, was provided by Ann Ferguson, PhD, of Oxford PharmaGenesis Inc., Newtown, PA, USA, and funded by Astellas Pharma Inc. Clinical trial information: NCT03504397 . [Table: see text]

Efficacy and safety of nanoliposomal irinotecan plus fluorouracil and folinic acid after irinotecan-based chemotherapy in patients with advanced pancreatic cancer: Results of the retrospective part of the NAPOLEON-2 study.

705 Background: Nanoliposomal irinotecan plus fluorouracil and folinic acid (nal-IRI/FU/LV; NFF) is the standard regimen after gemcitabine-based therapy for unresectable or recurrent pancreatic cancer (urPC). However, the efficacy and safety of NFF in patients who previously received irinotecan-based chemotherapy remain unclear. Methods: This retrospective study collected data from patients with urPC who received at least one previous chemotherapy before receiving NFF therapy at 21 hospitals in Japan between June 2020 and May 2021 (NAPOLEON-2 study). We analyzed antitumor efficacy, progression-free survival (PFS), and overall survival (OS) after the initiation of NFF and compared adverse events (AEs) between previous irinotecan users and non-users. Results: NFF was administered to 161 patients. The median follow-up period was 7.3 months (95% confidence interval [CI] = 5.6–8.9). All patients received prior gemcitabine-based therapy, and NFF was administered as the second-, third-, and fourth-or-later-line chemotherapy in 104, 41, and 16 patients, respectively. Eighteen patients (11%) previously received irinotecan. Patients’ characteristics did not significantly differ between irinotecan users (n = 18) and non-users (n = 143), excluding age (mean [range], 64 [38–78] vs. 68 [47–85] years; p = 0.01), the lung metastasis rate (44% vs. 14%; p &lt; 0.01), the treatment line (2nd/3rd/4th-or-later, 0%/56%/44% vs. 73%/22%/6%; p &lt; 0.01), and the pretreatment period (15.3 [6.8–45.0] vs. 9.1 [1.4–36.2] months; p &lt; 0.01). The median relative dose intensities of nal-IRI were 87.1% and 81.1% in irinotecan users and non-users, respectively (p = 0.28), and those of FU were 93.5% and 89.2%, respectively (p = 0.54). The objective response rate (6% vs. 5%; p = 0.90), disease control rate (44% vs. 53%; p = 0.49), PFS (2.8 months vs. 3.6 months; hazard ratio [HR] = 1.23; 95% CI = 0.74–2.05; p = 0.42), and OS (9.2 months vs. 8.0 months; HR = 0.88; 95% CI = 0.49–1.57; p = 0.66) did not differ between irinotecan users and non-users, nor did the rates of Grade 3/4 hematological (p = 0.68) and non-hematological (p = 0.13) AEs. Among irinotecan users, the duration of irinotecan-based therapy and the irinotecan-free interval before NFF did not affect the efficacy of NFF. Conclusions: NFF might be effective and safe even in patients with urPC who received irinotecan-based chemotherapy irrespective of its duration or the interval to NFF. Therefore, NFF is a possible treatment option after irinotecan-based chemotherapy. Further studies with a sufficient number of patients and a prospective design are warranted to examine the efficacy of NFF after irinotecan-based chemotherapy.

NET-02 final results: A randomised, phase II trial of liposomal irinotecan (nal-IRI)/5-fluorouracil (5-FU)/folinic acid or docetaxel as second-line (2L) therapy in patients (pts) with progressive poorly differentiated extrapulmonary neuroendocrine carcinoma (PD-EP-NEC).

646 Background: As demonstrated in the primary analysis of NET-02, nal-IRI/5-FU/folinic acid, but not docetaxel, met the primary endpoint of 6 month (mo) progression-free survival (PFS) rate in pts with progressive PD-EP-NEC. Here, the final results are presented. Methods: This was a multi-centre, randomised (1:1), phase II trial of IV nal-IRI (70mg/m2 free base)/5-FU (2400 mg/m2)/folinic acid, Q14 days (ARM A), or IV docetaxel (75mg/m2), Q21 days (ARM B), as 2L therapy in pts with progressive PD-EP-NEC, aimed at selecting a treatment for continuation to a phase III trial. On disease progression, pts in both arms could receive further systemic treatment as recommended by their physicians. Primary endpoint was 6 mo PFS rate; 80% power to demonstrate the one-sided 95% confidence interval (CI) of the 6 mo PFS rate excluded 15%, if the true rate was ≥30% (required level of efficacy); a rate of &lt;15% would give grounds for rejection (additional selection criteria: toxicity and quality of life (QoL)). Intention was to show that regimens were sufficiently active, but not to assess superiority of one regimen over the other. Secondary endpoints included objective response rate (ORR), PFS, overall survival (OS), toxicity, QoL (European Organisation for Research and Treatment of Cancer QLQ C30 and GINET21) and translational end-points. Results: Of 58 pts in 15 UK centres (Nov 18-Dec 21), 29 in ARM A (2 pts excluded for efficacy analysis: well-differentiated grade 3 (G3) neuroendocrine tumour and goblet cell adenocarcinoma), 29 in ARM B. Eight pts in both arms (27.6% each) received subsequent chemotherapy. Fifty-four pts (93%) have died; the primary end-point of 6-mo PFS rate was met in ARM A; ORR, median PFS and OS are also presented. Adverse events ≥ G3 occurred in 51.7% and 55.2% in ARM A and B with 1 and 6 discontinuations due to toxicity in ARM A and B, respectively. Health-related QoL was maintained (C30 functional scales &amp; global health status remained stable pre-progression) and potentially improved (sustained improvement in role functioning) with nal-IRI/5-FU/folinic acid, but not docetaxel (all C30 functional scales &amp; global health status worsened between baseline and week 18, and treatment-related symptoms also worsened in GINET21). Translational analysis is on-going. Conclusions: nal-IRI/5-FU warrants further evaluation in pts with PD-EP-NEC, with the results highlighting that conduct of randomised trials in this disease group of unmet need is possible and safe. Clinical trial information: NCT03837977 . [Table: see text]

Health-related quality of life in patients with RAS wild-type metastatic colorectal cancer treated with fluorouracil and folinic acid with or without panitumumab as maintenance therapy: An analysis of the Panama trial (AIO KRK0212).

51 Background: The PANAMA study demonstrated superior progression-free survival (PFS) with the addition of panitumumab (Pmab) to fluorouracil and folinic acid (FU/FA) as maintenance therapy following first-line induction therapy with FOLFOX/Pmab in patients with RAS wild-type metastatic colorectal cancer. We report health-related quality of life (HRQOL) analyses of the PANAMA study. Methods: HRQOL was assessed by European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) at every cycle of therapy until disease progression. All patients who received at least one dose of induction therapy and completed at least one HRQOL assessment were included into the analysis. HRQOL outcomes were mean changes in EORTC QLQ-C30 from baseline (prior to cycle 1 of induction therapy) to each cycle of treatment (both induction and maintenance therapy). The trial is registered with ClinicalTrials.gov (NCT01991873). Results: In total, 349/377 (93%) of the induction and 237/248 pts (96%) of the maintenance group completed at least one HRQOL assessment and were included in the HRQOL analysis population. There were no significant differences in any of the EORTC QLQ-C30 items between both treatment arms before induction therapy and at randomization. From baseline to cycle 6 of induction therapy there was significant improvement in mean EORTC QLQ-C30 global health status (GHS)/QOL, functioning (except for cognitive functioning) and symptom (except for nausea and vomiting, dyspnea, appetite loss, constipation, and financial difficulties) scores in the randomized population. During maintenance therapy, no significant differences between FU/FA plus Pmab and FU/FA alone were observed. In both arms of the trial, GHS/QOL scores were maintained or trended to improve from baseline (start of induction therapy) to cycle 10 of maintenance therapy (FU/FA plus Pmab: mean difference 9.48 [95% CI 1.96-17.00]; p=0.014); FU/FA arm (mean difference 6.52 [95% CI –1.9-14.95]; p=0.128). Conclusions: Using the established EORTC QLQ-C30 assessment, the addition of Pmab to FU/FA as maintenance therapy in patients with RAS wild-type metastatic colorectal cancer did not impair the HRQOL endpoints analyzed compared to FU/FA alone. These results, along with previously reported improvement in PFS, may support clinical decision-making concerning maintenance treatments. Clinical trial information: NCT01991873 .

Updates to NeoOPTIMIZE: An open-label, phase II trial and biomarker discovery platform to assess the efficacy of adaptive switching of modified FOLFIRINOX (mFFX) or gemcitabine/nab-paclitaxel (GA) as a neoadjuvant strategy for patients with resectable/borderline resectable and locally advanced unresectable pancreatic ductal adenocarcinoma (PDAC).

TPS776 Background: Neoadjuvant chemotherapy (NAC) and/or chemo-RT may confer benefit to patients with localized PDAC, by better tolerability, tumor down-staging, and increased R0 resections. mFFX or GA are the current NAC backbones; however, a lack of robust predictive biomarker(s) hampers identification of patients most likely to benefit from mFFX or GA. Further, desmoplastic stroma/poor vascularity compromise NAC efficacy, but angiotensin II receptor inhibitor, losartan, might remodel vascular perfusion to enhance chemotherapy activity. We designed the NeoOPTIMIZE trial for patients with newly diagnosed localized PDAC to provide a flexible clinical platform to: 1) evaluate the feasibility and efficacy of early switching of mFFX to GA, and 2) establish a robust biomarker/imaging discovery platform to optimize the NAC backbone. Methods: NeoOPTIMIZE (NCT04539808) is an open-label, non-randomized, phase II trial assessing the preliminary efficacy of an adaptive treatment strategy that allows for early switching of NAC in patients with localized PDAC. Sixty patients (n = 40 resectable/BRCP; n = 20 locally advanced unresectable [uLAPC]) will be enrolled to receive 2 months of preoperative mFFX (oxaliplatin, 85 mg/m2; folinic acid, 400 mg/m2; irinotecan, 150 mg/m2; 5-FU, 2400 mg/m2), then restaging by a multidisciplinary tumor board (multiD-TB). Absent progression (by panc protocol CT and CA19-9 decline/increase &lt; 30% from baseline), patients continue mFFX (4 cycles). If progression (by panc protocol CT; CA19-9 increase &gt; 30%), patients switch to GA (nab-paclitaxel, 125 mg/m2; gemcitabine, 1000 mg/m2) for 2 months. After 4 months of mFFX or mFFX/GA, another restaging multiD-TB will decide to proceed with: a) RT (if vascular involvement) then resection, b) resection, or c) continued chemo (if unresectable). Losartan (50 mg PO QD) is given throughout NAC and RT regimens. The primary endpoint estimates the proportion of resectable/BRPC patients with R0 resection. Assuming that the proportion of R0 is 60%, a sample size of 32 will provide a 95% CI (0.41, 076). To account for a 20% dropout, 40 patients will be enrolled towards primary endpoint. A separate exploratory cohort of 20 uLAPC patients will be enrolled. Secondary endpoints include DFS, PFS, OS, and AEs. Exploratory objectives include correlating clinical outcomes data with changes in blood-based biomarkers (CA19-9, ctDNA, circulating tumor cells etc.) and research DCE-MRI. To date, the trial has enrolled 19 patients: 8 resectable, 7 BRCP, and 4 uLAPC. Clinical trial information: NCT04539808 .

Multicenter observational study of nanoliposomal irinotecan and fluorouracil/leucovorin in patients with unresectable or recurrent pancreatic cancer (NAPOLEON-2): Final retrospective results.

706 Background: Nanoliposomal irinotecan (NAL-IRI) and fluorouracil with folinic acid (NFF) is the standard regimen after gemcitabine-based therapy for unresectable or recurrent pancreatic cancer (urPC). We conducted this NAPOLEON-2 study to investigate the efficacy and safety of NFF and explore the predictive or prognostic factors, retrospectively and prospectively, in the real world. We previously reported the interim analysis of the retrospective data 6 months after the end of data collection ( Ann Oncol. 2022;33(suppl 4): S289-S290). Here, we report the final data 1 year after data collection. Methods: We retrospectively collected data from urPC patients treated with NFF who received at least one previous chemotherapy in 21 hospitals in Japan from June 2020 to May 2021. Patient characteristics, treatment efficacy, and adverse events were analyzed. Overall survival (OS) and progression-free survival (PFS) were estimated using Kaplan–Meier analysis. OS and PFS among the therapeutic lines of NFF were also analyzed. Results: NFF was administered to 161 patients. The median follow-up period was 7.3 months (95% confidence interval [CI], 5.6–8.9); median age, 67 years (range, 38–85), with 73 female patients (45%). The Eastern Cooperative Oncology Group performance status was 0/1/2/3 in 74/76/10/1 patients, respectively. Nineteen patients (12%) had locally advanced disease; 142 (88%) had metastatic disease; 89 (55%) had liver metastasis; and 44 (27%) had peritoneal metastasis. All patients previously received gemcitabine-based therapy. NFF was administered as 2nd/3rd/4th-or-later-line therapy to 104/41/16 patients, respectively. The median OS was 8.1 months (95% CI, 7.1–9.7); median PFS, 3.4 months (95% CI, 2.8–4.4); overall response rate, 5%; and disease control rate, 52%. The relative dose intensity was 81.6% with NAL-IRI and 90.7% with fluorouracil. The initial dose of NAL-IRI was reduced in 57 patients (35%), mainly owing to UGT1A1 examination status (8%), followed by decreased organ function or worsened performance status (6%). Dosage reduction during treatment (independent of the initial dose reduction) was performed in 67 patients (42%), mainly owing to neutropenia (16%) and anorexia (11%). Frequent Grade 3/4 adverse events were neutropenia (24%), anorexia (12%), and leukopenia (12%). No Grade 5 adverse events were observed. The median OS and PFS for NFF in the 2nd-line group, compared with the 3rd-or-later-line group, were 7.6 vs 9.1 months (hazard ratio [HR], 0.92; 95% CI, 0.64–1.35; p = 0.68) and 2.9 vs 3.8 months (HR, 0.89; 95% CI, 0.64–1.24; p = 0.49), respectively. Conclusions: NFF had appropriate efficacy and manageable toxicity profiles, consistent with our previous report. NFF could be a candidate for 2nd-or-later-line regimens in the real world.

Prevalence of claudin 18.2 (CLDN18.2) and the association of biomarkers with clinical activity in patients with gastric or gastroesophageal adenocarcinoma (G/GEJa) treated with zolbetuximab.

466 Background: CLDN18.2, a targetable biomarker, is a tight junction protein normally confined to gastric mucosa of healthy tissue and often retained in G/GEJa. Zolbetuximab, a chimeric IgG1 monoclonal antibody, binds to CLDN18.2 and mediates cancer cell death via antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). Phase 2 FAST study results showed prolonged survival with zolbetuximab+EOX (epirubicin, oxaliplatin, capecitabine) vs EOX in CLDN18.2-positive G/GEJa. In ILUSTRO Cohort 2, confirmed partial responses (PRs) and stable disease (SD) were previously reported in 63.2% and 10.5%, respectively, of patients (pts) treated with zolbetuximab+mFOLFOX6 (modified 5-FU, folinic acid, oxaliplatin). Here is an analysis of CLDN18.2 expression and exploratory biomarkers from 2 studies of zolbetuximab alone or with mFOLFOX6 in G/GEJa. Methods: Data are from phase 1 (NCT03528629) and phase 2 (NCT03505320, ILUSTRO Cohorts 1 and 2) studies. Pts with CLDN18.2-positive locally advanced/metastatic G/GEJa received zolbetuximab alone (phase 1 [ineligible for SOC], n = 18; phase 2 Cohort 1 [≥3rd-line], n = 30) or with mFOLFOX6 (phase 2 Cohort 2 [1st-line], n = 21). Archival (any time before treatment), baseline (during screening or ≤3 months before first study treatment), and on-treatment (Cycle 3) tumor samples were collected when possible. CLDN18.2 expression and immune cell populations were assessed by IHC. Blood samples collected longitudinally while on treatment (phase 2 study) were analyzed for ADCC activity (ex vivo cell-based assay), circulating tumor antigens, and circulating tumor DNA (ctDNA). Results: Of 416 screened pts in both studies, 26.2% (n = 109), 9.6% (n = 40), and 36.1% (n = 150) had tumors that were CLDN18.2-positive in 1%–49%, 50%–74%, and ≥75% of tumor cells ( = strong to moderate staining intensity), respectively; 28.1% (n = 117) were CLDN18.2-negative (0/1+). Analysis of pre- and on-treatment tissue samples (n = 8 matched pairs) with zolbetuximab alone showed an increased trend in immune cell infiltration, with CD8+ T cells and CD163+ cells showing the most consistent trend. A trend of increased on-treatment vs baseline ADCC activity was observed in PBMCs collected from pts treated with zolbetuximab alone and with mFOLFOX6. Rapid and deep decreases in circulating tumor antigens (in pts with elevated antigen levels) and ctDNA were observed with best overall responses of both PR and SD. Conclusions: CLDN18.2 is a high-prevalence biomarker in G/GEJa. Treatment with zolbetuximab is associated with tumor and peripheral biomarker changes related to its proposed mechanism of action. Clinical responses observed in pts treated with zolbetuximab and mFOLFOX6 are associated with correlative biomarkers of activity including rapid deep molecular responses (ctDNA). Clinical trial information: NCT03528629 .

Folate shapes plant root architecture by affecting auxin distribution.

Folate (vitamin B9) is important for plant root development, but the mechanism is largely unknown. Here we characterized a root defective mutant, folb2, in Arabidopsis, which has severe developmental defects in the primary root. The root apical meristem of the folb2 mutant is impaired, and adventitious roots are frequently found at the root-hypocotyl junction. Positional cloning revealed that a 61-bp deletion is present in the predicted junction region of the promoter and the 5' untranslated region of AtFolB2, a gene encoding a dihydroneopterin aldolase that functions in folate biosynthesis. This mutation leads to a significant reduction in the transcript level of AtFolB2. Liquid chromatography-mass spectrometry analysis showed that the contents of the selected folate compounds were decreased in folb2. Arabidopsis AtFolB2 knockdown lines phenocopy the folb2 mutant. On the other hand, the application of exogenous 5-formyltetrahydrofolic acid could rescue the root phenotype of folb2, indicating that the root phenotype is indeed related to the folate level. Further analysis revealed that folate could promote rootward auxin transport through auxin transporters and that folate may affect particular auxin/indole-3-acetic acid proteins and auxin response factors. Our findings provide new insights into the important role of folic acid in shaping root structure.

Cycloguanil and Analogues Potently Target DHFR in Cancer Cells to Elicit Anti-Cancer Activity.

Dihydrofolate reductase (DHFR) is an established anti-cancer drug target whose inhibition disrupts folate metabolism and STAT3-dependent gene expression. Cycloguanil was proposed as a DHFR inhibitor in the 1950s and is the active metabolite of clinically approved plasmodium DHFR inhibitor Proguanil. The Cycloguanil scaffold was explored to generate potential cancer therapies in the 1970s. Herein, current computational and chemical biology techniques were employed to re-investigate the anti-cancer activity of Cycloguanil and related compounds. In silico modeling was employed to identify promising Cycloguanil analogues from NCI databases, which were cross-referenced with NCI-60 Human Tumor Cell Line Screening data. Using target engagement assays, it was found that these compounds engage DHFR in cells at sub-nanomolar concentrations; however, growth impairments were not observed until higher concentrations. Folinic acid treatment rescues the viability impairments induced by some, but not all, Cycloguanil analogues, suggesting these compounds may have additional targets. Cycloguanil and its most promising analogue, NSC127159, induced similar metabolite profiles compared to established DHFR inhibitors Methotrexate and Pyrimethamine while also blocking downstream signaling, including STAT3 transcriptional activity. These data confirm that Cycloguanil and its analogues are potent inhibitors of human DHFR, and their anti-cancer activity may be worth further investigation.

A Paternal Methylation Error in the Congenital Hydrocephalic Texas (H-Tx) Rat Is Partially Rescued with Natural Folate Supplements.

Folate deficiencies, folate imbalance and associated abnormal methylation are associated with birth defects, developmental delays, neurological conditions and diseases. In the hydrocephalic Texas (H-Tx) rat, 10-formyl tetrahydrofolate dehydrogenase (FDH) is reduced or absent from the CSF and the nuclei of cells in the brain and liver and this is correlated with decreased DNA methylation. In the present study, we tested whether impaired folate metabolism or methylation exists in sexually mature, unaffected H-Tx rats, which may explain the propagation of hydrocephalus in their offspring. We compared normal Sprague Dawley (SD, n = 6) rats with untreated H-Tx (uH-Tx, n = 6 and folate-treated H-Tx (TrH-Tx, n = 4). Structural abnormalities were observed in the testis of uH-Tx rats, with decreased methylation, increased demethylation, and cell death, particularly of sperm. FDH and FRα protein expression was increased in uH-Tx males but not in folate-treated males but tissue folate levels were unchanged. 5-Methylcytosine was significantly reduced in untreated and partially restored in treated individuals, while 5-hydroxymethylcytosine was not significantly changed. Similarly, a decrease in DNA-methyltransferase-1 expression in uH-Tx rats was partially reversed with treatment. The data expose a significant germline methylation error in unaffected adult male H-Tx rats from which hydrocephalic offspring are obtained. Reduced methylation in the testis and sperm was partially recovered by treatment with folate supplements leading us to conclude that this neurological disorder may not be completely eradicated by maternal supplementation alone.