Assessment of the Teratogenic Effect of Drugs on the Chicken Embryo.

Pre-clinical trials are an essential step that underpins the drug discovery, development, and safety process. During this process, animal testing is performed to determine the safety of new compounds and any potential adverse effects. Developmental toxicity tests are carried out to verify whether the drug has potential to cause congenital anomalies to the developing embryo/fetus. Chicken embryos are very useful for these purposes and present several advantages, such as low cost of production and housing, easy handling and manipulation, and rapid development in addition to sharing similarities to the human embryo at molecular, cellular, and anatomical levels. In this chapter, we bring methods for using the chicken embryo model for testing the teratogenic effects of drugs and assessing the main outcomes of them.

High-Resolution Respirometry for the Assessment of Teratogenic Chemicals.

Pesticides are often used in agriculture and residential areas to mitigate pests and weeds. These chemicals can enter aquatic ecosystems via runoff and rain events, exerting negative effects on aquatic species. In rapidly developing fish embryos, metabolic disruption can alter the developmental trajectory and alter ATP levels. Therefore, it is important to quantify mitochondrial integrity in organisms following exposure to pesticides. To achieve this, a high throughput method to assess pesticide effects on oxidative phosphorylation and mitochondria has been optimized for fish embryos. Fish embryos are first exposed to pesticides for 24 or 48 h, and oxygen consumption rates are measured using the Seahorse XFe24/96 Flux Analyzer (formerly Seahorse Biosciences, now Agilent). The assay utilizes a single embryo and precisely measures oxygen consumption and extracellular acidification. Based upon these measurements, characteristics related to mitochondrial bioenergetics are calculated to provide information on mitochondrial integrity. Using this approach, one can identify pesticides affecting the electron transport chain and ultimately ATP production. In this chapter, we describe the mitochondrial stress test to understand mitochondrial dysfunction and metabolic shifts within the fish embryo.

Optimization of the TeraTox Assay for Preclinical Teratogenicity Assessment.

Current animal-free methods to assess teratogenicity of drugs under development still deliver high numbers of false negatives. To improve the sensitivity of human teratogenicity prediction, we characterized the TeraTox test, a newly developed multilineage differentiation assay using 3D human-induced pluripotent stem cells. TeraTox produces primary output concentration-dependent cytotoxicity and altered gene expression induced by each test compound. These data are fed into an interpretable machine-learning model to perform prediction, which relates to the concentration-dependent human teratogenicity potential of drug candidates. We applied TeraTox to profile 33 approved pharmaceuticals and 12 proprietary drug candidates with known in vivo data. Comparing TeraTox predictions with known human or animal toxicity, we report an accuracy of 69% (specificity: 53%, sensitivity: 79%). TeraTox performed better than 2 quantitative structure-activity relationship models and had a higher sensitivity than the murine embryonic stem cell test (accuracy: 58%, specificity: 76%, and sensitivity: 46%) run in the same laboratory. The overall prediction accuracy could be further improved by combining TeraTox and mouse embryonic stem cell test results. Furthermore, patterns of altered gene expression revealed by TeraTox may help grouping toxicologically similar compounds and possibly deducing common modes of action. The TeraTox assay and the dataset described here therefore represent a new tool and a valuable resource for drug teratogenicity assessment.

A novel human stem cell-based biomarker assay for in vitro assessment of developmental toxicity.

BACKGROUND: Testing for developmental toxicity according to the current regulatory guidelines requires large numbers of animals, making these tests very resource intensive, time-consuming, and ethically debatable. Over the past decades, several alternative in vitro assays have been developed, but these often suffered from low predictability and the inability to provide a mechanistic understanding of developmental toxicity. METHODS: To identify embryotoxic compounds, we developed a human induced pluripotent stem cells (hiPSCs)-based biomarker assay. The assay is based on the differentiation of hiPSCs into functional cardiomyocytes and hepatocytes. Proper stem cell differentiation is investigated by morphological profiling and assessment of time-dependent expression patterns of cell-specific biomarkers. In this system, a decrease in the expression of the biomarker genes and morphology disruption of the differentiated cells following compound treatment indicated teratogenicity. RESULTS: The hiPSCs-based biomarker assay was validated with 21 well-established in vivo animal teratogenic and non-teratogenic compounds during cardiomyocyte and hepatocyte differentiation. The in vivo teratogenic compounds (e.g., thalidomide and valproic acid) markedly disrupted morphology, functionality, and the expression pattern of the biomarker genes in either one or both cell types. Non-teratogenic chemicals generally had no effect on the morphology of differentiated cells, nor on the expression of the biomarker genes. Compared to the in vivo classification, the assay achieved high accuracy (91%), sensitivity (91%), and specificity (90%). CONCLUSION: The assay, which we named ReproTracker®, is a state-of-the-art in vitro method that can identify the teratogenicity potential of new pharmaceuticals and chemicals and signify the outcome of in vivo test systems.

Assessment of Larval Toxicity and the Teratogenic Effect of Three Medicinal Plants Used in the Traditional Treatment of Urinary Tract Infections in Benin.

OBJECTIVE: Mangifera indica Linn, Bridelia ferruginea Benth, and Alstonia boonei De Wild are three plants commonly used in the traditional treatment of urinary tract infections in Benin. This study sets out to assess the cytotoxic and teratogenic effects of extracts of these plants on Artemia salina larvae and hen embryos. METHODS AND RESULTS: The aqueous and ethanolic extracts were obtained by maceration of the powders in solvents. Larval cytotoxicity was performed on Artemia salina larvae. The teratogenic effect of these plants was evaluated on chick embryos at 100 mg/kg and 300 mg/kg. The extracts were injected on the 7th and 14th days of incubation. The quality of the hatched chicks was evaluated by the Tona score followed by the hematological and the biochemical parameter assays. The extracts did not show cytotoxicity on the larvae. The eggs treated with plant extracts at 300 mg/kg significantly lowered the hatchability rate, except for the Mangifera indica Linn. The chicks obtained were all at the very good quality. Then, no significant variation was observed between hematological parameters except white blood cells. For the biochemical parameters, only ASAT showed some significant variations for a few extracts. It would be important to assess the genotoxicity of the plant extracts to determine more broader toxicity. These data justify the use of these medicinal plants in traditional Beninese medicine and constitute in fact a source of production of anti-infectious drugs.

Judicialização da saúde: análise dos processos judiciais do medicamento lenalidomida impetrados contra a Secretaria de Saúde do Estado de São Paulo para tratamento de mieloma múltiplo / Health's judicialization: analysis of the law-suits of the drug lenalidomide filed against the Health Department of the State of São Paulo for the treatment of multiple myeloma

O Mieloma Múltiplo é uma neoplasia maligna que acomete a medula óssea, sendo comumente diagnosticado em idosos. Para o tratamento no Sistema Único de Saúde (SUS) seguem-se as Diretrizes Diagnósticas e Terapêuticas do Mieloma Múltiplo do Ministério da Saúde, de 2015. O medicamento lenalidomida é um análogo da talidomida. A talidomida e lenalidomida são indicados para tratamento do mieloma. Ambos medicamentos causam efeitos teratogênicos nos fetos. A lenalidomida teve seu registro sanitário aprovado pela Agência Nacional de Vigilância Sanitária (ANVISA) para uso no país em dezembro de 2017. Os pacientes que necessitam do tratamento com o medicamento lenalidomida ingressam com processos judiciais para obtê-lo visto não constar da lista de medicamentos fornecidos pelo SUS. A diferença de preço dos dois medicamentos à base de lenalidomida fabricados e disponíveis no mundo é extremamente alta (Lenalid® e Revlimid®). No Brasil, somente o medicamento Revlimid® teve seu registro de patente junto ao Instituto Nacional de Propriedade Industrial e seu registro sanitário deferido junto à ANVISA, sendo o único autorizado para a comercialização no país, pela regulamentação da RDC ANVISA 191/2017. Considerando a política de Assistência Oncológica no Sistema Único de Saúde, o presente trabalho visou descrever o perfil dos processos judiciais para fornecimento do medicamento lenalidomida utilizada tratamento de Mieloma Múltiplo por determinações judiciais contra a Secretaria de Estado da Saúde de São Paulo. O perfil dos processos analisados confirma o observado na literatura sobre a judicialização da saúde, que, apesar de heterogênea e com características regionais, em muitos estudos, observa-se maior participação de pacientes oriundos de unidades de saúde privadas e assistentes jurídicos majoritariamente de advogados particulares. Além disso, os dados detectados/encontrados demonstraram que os pacientes são residentes em municípios com alto grau de desenvolvimento, segundo o Índice de Desenvolvimento Humano Municipal (IDHM), o qual atua como um indicador que avalia três dimensões do desenvolvimento humano: longevidade, educação e renda. Constatou-se também, pelo perfil dos processos judiciais descritos, a predominância de pacientes do sexo masculino. Descreveram-se os aspectos de regulamentação e de controle sanitário do medicamento lenalidomida, em comparação à talidomida no Brasil, além das normativas da ANVISA vigentes sobre o controle da substância lenalidomida, diante dos riscos associados (segurança do paciente - teratogênese) e as questões relativas a patente e fenômeno de judicialização da saúde no país.

Multiple myeloma is a malignant neoplasm that affects the bone marrow and is com-monly diagnosed in the elderly. For treatment in the Unified Health System (SUS), the Ministry of Health's 2015 Myeloma Diagnostic and Therapeutic Guidelines are followed. The medication lenalidomide is an analogue of thalidomide. Thalidomide and lenalidomide are indicated for the treatment of myeloma. Both drugs have teratogenic effects on fetuses. Lenalidomide had its health record approved by the National Health Surveillance Agency (ANVISA) for use in the country in December 2017. Patients who need treatment with the drug lenalidomide file lawsuits to obtain it since it is not on the list of drugs provided by SUS. The price difference of the two lenalidomide-based drugs manufactured and available worldwide is extremely high (Lenalid® and Revlimid®). In Brazil, only the drug Revlimid® had its patent registra-tion with the National Institute of Industrial Property and its sanitary registration granted with ANVISA, being the only one authorized for commercialization in the country, by the regulation of RDC ANVISA 191/2017. Considering the policy of Onco-logical Assistance in the Unified Health System, the present study aimed to describe the profile of the legal proceedings for the supply of the drug lenalidomide used in the treatment of Multiple Myeloma due to judicial orders against the São Paulo State De-partment of Health. The profile of the analyzed cases confirms that observed in the literature on the judicialization of health, which, although heterogeneous and with re-gional characteristics, in many studies, there is a greater participation of patients from private health units and legal assistants mostly from private lawyers . In addition, the data detected / found showed that patients are residents of municipalities with a high degree of development, according to the Municipal Human Development Index (MHDI), which acts as an indicator that assesses three dimensions of human devel-opment: longevity, education and income. It was also verified, by the profile of the judicial processes described, the predominance of male patients. The regulatory and sanitary control aspects of the drug lenalidomide were described, in comparison to thalidomide in Brazil, in addition to the ANVISA regulations in force on the control of the lenalidomide substance, in view of the associated risks (patient safety - teratogenesis) and the relative issues the patent and phenomenon of judicialization of health in the country.

Risk management of teratogenic medicines: A systematic review.

AIM: To systematically identify studies of implementing risk management measures when prescribing teratogenic medicines for women of childbearing age and studies reporting risk perceptions of teratogenic medications. METHODS: MEDLINE, CINAHL, Scopus, EMBASE, and International Pharmaceutical Abstracts were searched. Studies were included in the risk management section if they reported any of the following risk management measures: teratogenic counseling, contraceptive counseling, pregnancy testing before starting treatment, pregnancy testing during treatment, use of contraception before starting treatment, and use of contraception during treatment. Studies were included in the perceptions section if they reported perceived teratogenic risk as numerical value. RESULTS: Fifty-five studies were included in the risk management section and seven studies were included in the perceptions sections. Prevalence of risk management measures varied as follows: teratogenic counseling (9.5%-99.3%), contraceptive counseling (6.1%-98%), pregnancy testing before starting treatment (0%-95.1%), pregnancy testing during treatment (12.7%-100%), contraception use before starting treatment (15.7%-94%), and contraception use during treatment (1.7%-100%). A proper estimation of the teratogenic risk was reported for thalidomide (by general practitioners and obstetric/gynecologists), for etretinate (by pregnant women), and for misoprostol (by pregnant and nonpregnant women). An under-estimation was reported for warfarin and retinoids (by general practitioners and obstetric/gynecologists). And over-estimation was reported for thalidomide, valproate, lithium, isotretinoin, phenytoin, warfarin and etretinate by different populations. CONCLUSION: Considerable variation in the implementation of risk management measures when prescribing teratogenic medicines to women of childbearing age is reported in the literature. A common tendency to over-estimate the risk of teratogenic medications was evident.

Safety of New Biologics (Vedolizumab and Ustekinumab) and Small Molecules (Tofacitinib) During Pregnancy: A Review.

Two new biological drugs (vedolizumab and ustekinumab) and one small molecule (tofacitinib) have been recently approved for the treatment of inflammatory bowel disease. Therefore, we must be familiar with the safety of these "new" drugs during pregnancy and breastfeeding. In the present article, we critically review available data on the safety of new biologics (vedolizumab and ustekinumab) and small molecules (tofacitinib) during pregnancy and breastfeeding, with special focus on women with inflammatory bowel disease. Bibliographical searches (MEDLINE) up to April 2020 were performed. The timing and mechanisms of placental transfer of vedolizumab and ustekinumab are expected to be similar to anti-TNF agents. Animal studies show no evidence of adverse effects on pre- or post-natal development after administration of vedolizumab and ustekinumab. Just a few studies including patients treated with vedolizumab or ustekinumab during pregnancy have been published, reporting uneventful pregnancies in most cases. The clinical programme of both drugs and post-marketing studies showed no new safety concerns. Due to the expected safety of vedolizumab and ustekinumab during pregnancy, it may be recommended to plan the final pregnancy dose approximately 8 or 12 weeks, respectively, before the estimated date of delivery. Live vaccines should be avoided for up to a year in children exposed in utero to vedolizumab or ustekinumab unless drug elimination has been documented. Miniscule amounts of vedolizumab and ustekinumab are transferred to breast milk, so breastfeeding is probably safe. There is no evidence of adverse effect of vedolizumab or ustekinumab paternal exposure. Regarding tofacitinib, it is reasonable to assume that this molecule crosses the placenta from the beginning of pregnancy. In animal studies, tofacitinib was feticidal and teratogenic in rats and rabbits, although at exposures many times greater than the standard human dose. Reported outcomes of pregnancy cases identified from tofacitinib randomised controlled trials, post-approval and non-interventional studies, and spontaneous adverse-event reporting appear similar to those observed in the general population. Nevertheless, at present, the use of tofacitinib during pregnancy should be avoided. Although no human studies have reported outcomes of breastfeeding with small molecules such as tofacitinib, this drug is present in lactating rat milk so, at present, breastfeeding should be avoided. Pregnancy among patients with paternal exposure to tofacitinib appears to be safe. In summary, we can conclude that new biologic agents (vedolizumab and ustekinumab) and small molecules (tofacitinib) should be used during pregnancy only if the benefits to the mother outweigh the risks to the mother and unborn child.

Safety evaluation of the venom from scorpion Rhopalurus junceus: Assessment of oral short term, subchronic toxicity and teratogenic effect.

Rhopalurus junceus is the most common scorpion in Cuba and the venom is often used as a natural product for anti-cancer therapy. Despite this, no study has been published concerning its toxicological profile. The aim of the study was characterizing the short-term, subchronic toxicity and the teratogenic potential of Rhopalurus junceus scorpion venom by oral route in mice. Short-term oral toxicity was test in both sexes NMRI mice that received 100 mg/kg/day of scorpion venom extract for 28 days. For the subchronic study, mice were administered with three doses (0.1, 10, and 100 mg/kg) by oral route for 90 days. Teratogenic potential was tested in pregnant mice administered from day 6-15 post conception. Significant differences were observed in body weight and food intake of animal treated for short-term and subchronic assays. Variations in serum urea and cholesterol were observed after 90 days oral treatment. Spontaneous findings not related to the treatment were reveal in histology evaluation. Exposure in pregnant mice did not produce maternal toxicity. Signs of embryo-fetal toxicity were not observed. The current study provides evidence that exposure to low or moderate dose of Rhopalurus junceus scorpion venom by oral route did not affect health of animals and has low impact on reproductive physiology.

Exposure-based assessment of chemical teratogenicity using morphogenetic aggregates of human embryonic stem cells.

Pluripotent stem cells recapitulate many aspects of embryogenesis in vitro. Here, we established a novel culture system to differentiate human embryonic stem cell aggregates (HESCA), and evaluated its utility for teratogenicity assessment. Culture of HESCA with modulators of developmental signals induced morphogenetic and molecular changes associated with differentiation of the paraxial mesoderm and neuroectoderm. To examine impact of teratogenic exposures on HESCA differentiation, 18 compounds were tested, for which adequate information on in vivo plasma concentrations is available. HESCA treated with each compound were examined for gross morphology and transcript levels of 15 embryogenesis regulator genes. Significant alterations in the transcript levels were observed for 94% (15/16) of the teratogenic exposures within 5-fold margin, whereas no alteration was observed for 92% (11/12) of the non-teratogenic exposures. Our study demonstrates that transcriptional changes in HESCA serve as predictive indicator of teratogenicity in a manner comparable to in vivo exposure levels.

Effects of nonylphenols on embryonic development and metamorphosis of Xenopus laevis: FETAX and amphibian metamorphosis toxicity test (OECD TG231).

Nonylphenols (NPs) are a group of endocrine-disrupting surfactants that mimic estrogen. To determine the developmental toxicity and thyroid-disrupting effect of NPs, the effects of exposure to nonylphenol (NP), 4-nonylphenol (4-NP), and nonylphenol ethoxylate (NP-12) were examined according to the frog embryo teratogenesis assay-Xenopus (FETAX) and Organization for Economic Co-operation and Development test guidelines 231 (TG231). In FETAX, the LC50 values of NP, 4-NP, and NP-12 were 59.14 mg/L, 10.13 mg/L, and 14.60 mg/L, respectively. At 10.0 mg/L, NP, 4-NP, and NP-12 significantly decreased the total length of tadpoles, and NP and 4-NP increased gut malformation and bent tails. In surviving tadpoles, the EC50 values for malformation of NP, 4-NP, and NP-12 were 4.66, 6.51, and 13.08 mg/L, respectively. The teratogenic indices of NP, 4-NP, and NP-12 were 12.69, 1.56, and 1.08, respectively, suggesting the teratogenic potential of NP and 4-NP. In a range-finder assay for TG231, the 96-h LC50 values of NP, 4-NP, and NP-12 were 2.0, 2.0, and 10.57 mg/L, respectively. When NF stage 51 larvae were exposed for 21 days, larval growth was inhibited by NP, 4-NP, and NP-12 at 0.67, 0.07, and 0.37 mg/L, respectively. 4-NP at 0.07 mg/L accelerated the developmental stage and significantly increased hind limb length, while 0.67 mg/L 4-NP delayed the developmental stage and decreased hind limb length, suggesting a bimodal effect of 4-NP on metamorphosis. NP and NP-12 at test concentrations did not alter the larval stage, but NP-12 at 0.37 mg/L significantly decreased total length and tail length, suggesting growth inhibition in larvae. The total colloid area of thyroid follicles was significantly increased by 0.07 mg/L 4-NP but not by NP and NP-12, suggesting that 4-NP may interfere with thyroid function. Together, the developmental toxicity of NPs was in the following order: 4-NP, NP-12, and NP. 4-NP may alter metamorphosis driven by thyroid hormones in X. laevis.

Histological and Histochemical Profile for Teratological Assessment in Mus musculus.

Histological analysis of mouse embryos, fetuses, or newborns remains one the most common methods and in some cases the "gold standard" used in teratology studies to detect abnormal morphogenesis during development. Histochemistry methods are based on the selectivity of certain chemical compounds for certain cellular or tissue components, several of them related to specific maturation processes. In this chapter, specific histochemistry techniques that allow for the monitoring of critical stages of tissue and organ formation, such as skeleton and muscle differentiation, neuronal maturation, neuronal connectivity, and neurodevelopment after teratogenic exposure are described in detail.

Frog Embryo Teratogenesis Assay-Xenopus (FETAX): Use in Alternative Preclinical Safety Assessment.

The primary objective of this protocol is to provide alternative developmental toxicity data using the frog embryo teratogenesis assay-Xenopus (FETAX) model for preclinical safety assessment. FETAX is most useful in the prioritization of developmental toxicity hazard for sets of discovery-level compounds. Assessment of teratogenic potential is based on teratogenic indices (TI), which measure the teratogenic potential of a given test material. The relative hazard ranking is based on a set of weighted endpoints that include developmental toxicity potency, teratogenic potential, and growth inhibition. Because of the importance of potency and teratogenic potential in determining relative hazard, these endpoints are weighted 2×. Growth inhibition is weighted 1×. These data determine a generic ranking. The generic hazard rank is based on numerical endpoint data derived from an assessment of potency, teratogenic potential as determined by the TI value, and concentration at which growth inhibition is detected when expressed as a proportion of the 4-d LC50 value. With the generic rank, the lower the generic hazard ranking the greater the developmental toxicity hazard relative to the other materials evaluated. However, the relative severity of the malformation syndromes induced is not incorporated into the generic ranking process. An objective evaluation of the severity of the deformities induced is an important process in the evaluation of FETAX results; therefore, a final definitive ranking process is used. A final definitive ranking is determined using the generic rank and the severity of the malformations induced (weighted 5×).