1
|
Catlin NR, Bowman CJ, Campion SN, Lewis EM, Nowland WS, Stethem C, Cappon GD. The postnatal resolution of developmental toxicity induced by pharmacological diacylglycerol acyltransferase 2 (DGAT2) inhibition during gestation in rats. Toxicol Sci 2022; 189:225-236. [PMID: 35866640 DOI: 10.1093/toxsci/kfac077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ervogastat (PF-06865571) is a small molecule diacylglycerol acyltransferase 2 (DGAT2) inhibitor being developed for the oral treatment of non-alcoholic steatohepatitis (NASH) with liver fibrosis. DGAT2 is a key enzyme in triglyceride synthesis in tissues and in regulating energy metabolism. Fertility and developmental toxicity studies with ervogastat were conducted in female rats and rabbits. There were no effects on female rat fertility or rabbit embryo-fetal development. Administration of ervogastat to pregnant rats during organogenesis reduced fetal weight and caused higher incidences of bent bones in fetuses that were shown to resolve by postnatal day 28 and were therefore considered to be transient variations secondary to developmental delay. Extended dosing in rats through the end of gestation and lactation (pre- and post-natal development study) caused impaired skin development, reduced offspring viability and growth retardation. The spectrum of developmental effects in rats is consistent with the intended pharmacology (altered triglyceride metabolism) and the transient nature of the skeletal findings, along with the late gestational window of sensitivity for the effects on skin barrier development, reduce the concern for potential adverse developmental effects following unintended early gestational exposure to ervogastat in humans where treatment can be discontinued once pregnancy is determined.
Collapse
Affiliation(s)
- Natasha R Catlin
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Christopher J Bowman
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Sarah N Campion
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Elise M Lewis
- Charles River Laboratories, Inc, Safety Assessment, Horsham, PA, USA
| | - William S Nowland
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Christine Stethem
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Gregg D Cappon
- Drug Safety Research, Development, & Medical, Pfizer Worldwide Research & Development, Groton, CT, USA
| |
Collapse
|
2
|
Catlin NR, Stethem C, Bowman CJ, Campion SN, Nowland WS, Cappon GD. Knockout mouse models are predictive of malformations or embryo-fetal death in drug safety evaluations. Reprod Toxicol 2021; 99:138-143. [PMID: 33065206 DOI: 10.1016/j.reprotox.2020.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Traditionally, understanding potential developmental toxicity from pharmaceutical exposures has been based on the results of ICH guideline studies in two species. However, support is growing for the use of weight of evidence approaches when communicating the risk of developmental toxicity, where the intended pharmacologic mode of action affects fundamental pathways in developmental biology or phenotypic data from genetically modified animals may increasingly be included in the overall assessment. Since some concern surrounds the use of data from knockout (KO) mice to accurately predict the risk for pharmaceutical modulation of a target, a deeper understanding of the relevance and predictivity of adverse developmental effects in KO mice for pharmacological target modulation is needed. To this end, we compared the results of embryo-fetal development (EFD) studies for 86 drugs approved by the FDA from 2017 to 2019 that also had KO mouse data available in the public domain. These comparisons demonstrate that data from KO mouse models are overall highly predictive of malformations or embryo-fetal lethality (MEFL) from EFD studies, but less so of a negative outcome in EFD studies. This information supports the use of embryo-fetal toxicity data in KO models as part of weight of evidence approaches in the communication of developmental toxicity risk of pharmaceutical compounds.
Collapse
|
3
|
Catlin NR, Bowman CJ, Campion SN, Davenport SD, Esler WP, Kumpf SW, Lewis EM, Nowland WS, Ross TT, Stedman DS, Stethem C, Cappon GD. Inhibition of ACC causes malformations in rats and rabbits: comparison of mammalian findings and alternative assays. Toxicol Sci 2020; 179:183-194. [PMID: 33247737 DOI: 10.1093/toxsci/kfaa169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Acetyl-CoA carboxylase (ACC) is an enzyme within the de novo lipogenesis (DNL) pathway and plays a role in regulating lipid metabolism. Pharmacologic ACC inhibition has been an area of interest for multiple potential indications including oncology, acne vulgaris, metabolic diseases such as type 2 diabetes mellitus, and non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. A critical role for ACC in de novo synthesis of long-chain fatty acids during fetal development has been demonstrated in studies in mice lacking Acc1, where the absence of Acc1 results in early embryonic lethality. Following positive predictions of developmental toxicity in alternative in vitro assays (positive in murine embryonic stem cell [mESC] assay and rat whole embryo culture, but negative in zebrafish), developmental toxicity (growth retardation and dysmorphogenesis associated with disrupted midline fusion) was observed with the oral administration of the dual ACC1 and 2 inhibitor, PF-05175157, in Sprague Dawley rats and New Zealand White rabbits. The results of these studies are presented here to make comparisons across the assays, as well as mechanistic insights from the mESC assay demonstrating high ACC expression in the mESC and that ACC induced developmental toxicity can be rescued with palmitic acid providing supportive evidence for DNL pathway inhibition as the underlying mechanism. Ultimately, while the battery of alternative approaches and weight-of-evidence case were useful for hazard identification, the embryo-fetal development studies were necessary to inform the risk assessment on the adverse fetal response, as malformations and/or embryo fetal lethality were limited to doses that caused near complete inhibition of DNL.
Collapse
Affiliation(s)
- Natasha R Catlin
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Christopher J Bowman
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Sarah N Campion
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Scott D Davenport
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - William P Esler
- Internal Medicine Research Unit, Pfizer Worldwide Research & Development, Cambridge, MA, USA
| | - Steven W Kumpf
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Elise M Lewis
- Charles River Laboratories, Inc, Safety Assessment, Horsham, PA, USA
| | - William S Nowland
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Trenton T Ross
- Internal Medicine Research Unit, Pfizer Worldwide Research & Development, Cambridge, MA, USA
| | - Donald S Stedman
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Christine Stethem
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| | - Gregg D Cappon
- Drug Safety Research and Development, Pfizer Worldwide Research & Development, Groton, CT, USA
| |
Collapse
|
4
|
Cassar S, Beekhuijzen M, Beyer B, Chapin R, Dorau M, Hoberman A, Krupp E, Leconte I, Stedman D, Stethem C, van den Oetelaar D, Tornesi B. A multi-institutional study benchmarking the zebrafish developmental assay for prediction of embryotoxic plasma concentrations from rat embryo-fetal development studies. Reprod Toxicol 2019; 86:33-44. [PMID: 30876927 DOI: 10.1016/j.reprotox.2019.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 12/24/2018] [Accepted: 02/08/2019] [Indexed: 01/11/2023]
Abstract
Predicting embryotoxicity of pharmaceutical compounds or industrial chemicals is crucial for public safety. Conventional studies which monitor embryo-fetal development in rats and rabbits are costly and time consuming. Alternative assays which are simpler and less costly are being pursued. The purpose of this research was to assess the capacity for the zebrafish development assay to predict mammalian plasma levels that are embryotoxic. Previously published data on rat plasma levels associated with embryotoxicity were used to guide concentration ranges for each of 25 chemicals dissolved in the media bathing developing zebrafish embryos. Embryotoxic media concentrations were compared to embryotoxic rat plasma concentrations. Assays were conducted in parallel at multiple sites as a consortium effort through the Health and Environmental Sciences Institute (HESI). Considering results from all sites, the zebrafish embryo development assay predicted (within 1-log) the rat maternal exposure levels associated with embryotoxicity 75% of the time.
Collapse
|