Evidence map›Paper›PMID 20725726›Full record

ArticleCancer chemotherapy and pharmacology2011

Plasma and CNS pharmacokinetics of O4-benzylfolic acid (O4BF) and metabolite in a non-human primate model.

Meredith K Chuk, Diane E Cole, Cynthia McCully, Natalia A Loktionova, Anthony E Pegg, Robert J Parker, Gary Pauly, Brigitte C Widemann, Frank M Balis, Elizabeth Fox

Open access · greenAbstract read
In one paragraph

Article in Cancer chemotherapy and pharmacology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
0.1field-weighted citation impact, top 45% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed, 1 citations in OpenAlex.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 6 institutions in 1 country.

Meredith K ChukPediatric Oncology Branch, National Cancer Institute, 10 Center Drive, Building 10/Rm 1W-5750, Bethesda, MD 20892, USA. chukmk@gmail.com
Diane E Cole
Cynthia McCully
Natalia A Loktionova
Anthony E Pegg
Robert J Parker
Gary Pauly
Brigitte C Widemann
Frank M Balis
Elizabeth Fox
Children's Hospital of Philadelphia · USNational Cancer Institute · USNational Institutes of Health · USPennsylvania State University · USCenter for Drug Evaluation and Research · USFrederick National Laboratory for Cancer Research · US

Funding

Therapies for patients with rare tumors and genetic tumor predispositionZIASC010354 · NCI · DIVISION OF CLINICAL SCIENCES - NCI · PI WIDEMANN, BRIGITTE · 2009 to 2025
$19.2M
ALKYLTRANSFERASE INHIBITORS FOR CANCER CHEMOTHERAPYR01CA071976 · NCI · PENNSYLVANIA STATE UNIV HERSHEY MED CTR · PI KANUGULA, SREENIVAS · 1996 to 2010
$2.7M
NOVEL DRUGS FOR CHILDREN WITH CANCER &NEUROFIBROMATOSISZ01SC010354 · SC · DIVISION OF CLINICAL SCIENCES - NCI · PI WIDEMANN, BRIGITTE · 2000 to 2008
$473k
Intramural NIH HHS Z01 SC010354NCI NIH HHS R01 CA071976NCI NIH HHS R01CA-071976
6 · The paper itself

Abstract

purposeO(6)-alkylguanine-DNA alkyltransferase (AGT) repairs DNA damage from alkylating agents by transferring the alkyl adducts from the O(6)-position of guanine in DNA to AGT. The folate analog O(4)-benzylfolic acid (O(4)BF) is an inhibitor of AGT with reported selectivity of the alpha-folate receptor in tumors. We studied plasma and cerebrospinal fluid (CSF) pharmacokinetics and CSF penetration of O(4)BF in a non-human primate model.

methodsRhesus monkeys (Macaca mulatta) received O(4)BF (10-50 mg/kg) intravenously, and serial blood and CSF samples were obtained. Analyte concentrations in plasma were measured by HPLC/photo diode array, and an HPLC/MS/MS assay was used for CSF samples.

resultsA putative metabolite of O(4)BF was detected in plasma and CSF. O(4)BF and the metabolite inactivated purified AGT with ED(50) of 0.04 mcM. The median clearance of O(4)BF was 8 ml/min/kg and half-life was 1.1 h. The metabolite had a substantially longer half-life (>20 h) and greater AUC than O(4)BF. The AUC of the metabolite increased disproportionately to the dose of O(4)BF, suggesting saturable elimination. CSF penetration of O(4)BF and its metabolite was < 1%. At the 50 mg/kg dose level, the C(max) in CSF for O(4)BF was less than 0.09 mcM and for the metabolite the C(max) ranged from 0.02 to 0.04 mcM (O(4)BF equivalents).

conclusionsConcentrations of O(4)BF and the metabolite in CSF exceeded the ED(50) of AGT; however, recently reported lack of receptor specificity and pharmacokinetic data suggesting saturable elimination of both O(4)BF and its metabolite may limit dose-escalation and future clinical development of this agent.

Indexed as

AnimalsBrainFolic AcidMacaca mulattaO(6)-Methylguanine-DNA MethyltransferaseFolic AcidO(4)-benzylfolic acidO(6)-Methylguanine-DNA Methyltransferase

Identifiers

PMID20725726
PMCPMC6675565
OpenAlexW2093944075

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.