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1.
JBRA Assist Reprod ; 28(1): 13-20, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38224574

RESUMO

OBJECTIVE: To evaluate the efficacy of sublingually administered human chorionic gonadotropin (HCG) in combination with clomiphene citrate (CC) or letrozole (LTZ) for ovulation induction. METHODS: In this prospective, double-blind, randomized study, the patients were divided into two placebo groups and two intervention groups using CC, LTZ, and HCG. RESULTS: There were no statistically significant differences in ovulation induction between the groups. We compared endometrial thickness at the beginning of the cycle and during the pre-ovulatory period, and detected a moderately positive correlation when CC was administered with HCG. CONCLUSIONS: Sublingual HCG with CC caused a moderately positive correlation with endometrial thickening when compared with that at the beginning of the cycle and during the pre-ovulatory period. There was no significant change in the number of pre-ovulatory follicles.


Assuntos
Infertilidade Feminina , Feminino , Humanos , Gonadotropina Coriônica/uso terapêutico , Clomifeno/uso terapêutico , Clomifeno/farmacologia , Fármacos para a Fertilidade Feminina/uso terapêutico , Infertilidade Feminina/etiologia , Letrozol , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Indução da Ovulação/efeitos adversos , Estudos Prospectivos , Triazóis/farmacologia , Triazóis/uso terapêutico , Método Duplo-Cego
2.
Clin Drug Investig ; 43(9): 699-706, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37594640

RESUMO

BACKGROUND AND OBJECTIVES: Palbociclib is a cyclin-dependent kinase 4/6 inhibitor that is approved in the United States for the treatment of hormone receptor‒positive (HR+)/human epidermal growth factor receptor‒2 negative (HER2-) advanced breast cancer (ABC). The objectives of this expanded access trial were to provide palbociclib in combination with letrozole to patients with HR+/HER2- ABC in Argentina, Brazil, Colombia, and Mexico who were candidates for letrozole therapy before commercial availability of palbociclib, and to evaluate the safety and tolerability of palbociclib plus letrozole. PATIENTS AND METHODS: Postmenopausal women aged ≥ 18 years with HR+/HER2- ABC were eligible to participate in this study. Patients received palbociclib 125 mg once daily (3/1 schedule) and letrozole 2.5 mg once daily (continuous schedule). Safety, objective response rate (ORR), and duration of treatment were evaluated. RESULTS: A total of 130 patients were treated with palbociclib plus letrozole (Argentina, n = 33; Brazil, n = 35; Colombia, n = 28; Mexico, n = 34). The most common treatment-emergent adverse events (TEAEs) of any grade were neutropenia (70.0%), leukopenia (34.6%), anemia (33.8%), decreased neutrophil count (27.7%), and thrombocytopenia (24.6%); 22.3% of patients required a palbociclib dose reduction due to adverse events (AEs). Serious AEs were reported in 32 patients (24.6%). The ORR was 24.8% (95% confidence interval 17.6‒33.2), and the median duration of treatment was 10.6 months (range 0.1‒29.3). CONCLUSION: Palbociclib in combination with letrozole was generally well tolerated with a clinically manageable safety profile; the observed ORR supported treatment benefit in Latin American women with HR+/HER2- ABC. TRIAL REGISTRY: ClinicalTrials.gov, NCT02600923.


This study was done to learn more about the safety of 2 medicines together for women with advanced breast cancer after menopause. All 130 women in the study had the most common kind of breast cancer and were from Argentina, Brazil, Colombia, and Mexico. Everyone took 2 oral medicines called palbociclib and letrozole during the study. The researchers looked for any side effects experienced by the women while taking these medicines together. Another goal of the study was to see how well the treatment worked. Blood tests showed 70.0% of women had a side effect where they had a lower number of a type of white blood cell called a neutrophil. In total, 34.6% of women had low levels of another white blood cell called a leukocyte. These blood test results can mean a person is more likely to get infections. Serious side effects were experienced by 24.6% of the women, which meant these were life-threatening, caused lasting problems, or they needed hospital care. To cope with their side effects, 22.3% of the women switched to a lower palbociclib dose; 24.8% of the women had an overall response, which meant they either had a decrease in their tumor size or all cancer signs disappeared from their body. The most common length of time in the study was 10.6 months and the longest time was 29.3 months. The results of this study support using palbociclib plus letrozole to treat women who live in Latin America with advanced breast cancer after menopause.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Letrozol/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , América Latina , Pós-Menopausa , Receptor ErbB-2/metabolismo , Resultado do Tratamento , Receptores de Estrogênio/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Molecules ; 28(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37446555

RESUMO

INTRODUCTION: The third-generation of aromatase inhibitors (AIs)-Exemestane (Exe), Letrozole (Let), and Anastrozole (Ana)-is the main therapeutic approach applied for estrogen receptor-positive (ER+) breast cancer (BC), the most common neoplasm in women worldwide. Despite their success, the development of resistance limits their efficacy. Genistein (G), a phytoestrogen present in soybean, has promising anticancer properties in ER+ BC cells, even when combined with anticancer drugs. Thus, the potential beneficial effects of combining G with AIs were investigated in sensitive (MCF7-aro) and resistant (LTEDaro) BC cells. METHODS: The effects on cell proliferation and expression of aromatase, ERα/ERß, and AR receptors were evaluated. RESULTS: Unlike the combination of G with Ana or Let, which negatively affects the Ais' therapeutic efficacy, G enhanced the anticancer properties of the steroidal AI Exe, increasing the antiproliferative effect and apoptosis relative to Exe. The hormone targets studied were not affected by this combination when compared with Exe. CONCLUSIONS: This is the first in vitro study that highlights the potential benefit of G as an adjuvant therapy with Exe, emphasizing, however, that soy derivatives widely used in the diet or applied as auxiliary medicines may increase the risk of adverse interactions with nonsteroidal AIs used in therapy.


Assuntos
Antineoplásicos , Neoplasias da Mama , Feminino , Humanos , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Genisteína/farmacologia , Genisteína/uso terapêutico , Letrozol , Antineoplásicos/uso terapêutico , Nitrilas/uso terapêutico
4.
J Clin Oncol ; 41(29): 4664-4668, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37290029

RESUMO

PURPOSE: Self-administered oncology drugs contribute disproportionately to Medicare Part D spending; prices often remain high even after generic entry. Outlets for low-cost drugs such as Mark Cuban Cost Plus Drug Company (MCCPDC) offer opportunities for decreased Medicare, Part D, and beneficiary spending. We estimate potential savings if Part D plans obtained prices such as those offered under the MCCPDC for seven generic oncology drugs. METHODS: Using the 2020 Medicare Part D Spending dashboard, Q3-2022 Part D formulary prices, and Q3-2022 MCCPDC prices for seven self-administered generic oncology drugs, we estimated Medicare savings by replacing Q3-2022 Part D unit costs with costs under the MCCPDC plan. RESULTS: We estimate potential savings of $661.8 million (M) US dollars (USD; 78.8%) for the seven oncology drugs studied. Total savings ranged from $228.1M USD (56.1%) to $2,154.5M USD (92.4%) compared with 25th and 75th percentiles of Part D plan unit prices. The median savings replacing Part D plan prices were abiraterone $338.0M USD, anastrozole $1.2M USD, imatinib 100 mg $15.6M USD, imatinib 400 mg $212.0M USD, letrozole $1.9M USD, methotrexate $26.7M USD, raloxifene $63.8M USD, and tamoxifen $2.6M USD. All 30-day prescription drug prices offered by MCCPDC generated cost savings except for three drugs offered at the 25th percentile Part D formulary pricing: anastrozole, letrozole, and tamoxifen. CONCLUSION: Replacing current Part D median formulary prices with MCCPDC pricing could yield significant savings for seven generic oncology drugs. Individual beneficiaries could save nearly $25,200 USD per year for abiraterone or between $17,500 USD and $20,500 USD for imatinib. Notably, Part D cash-pay prices for abiraterone and imatinib under the catastrophic phase of coverage were still more expensive than baseline MCCPDC prices.


Assuntos
Medicare Part D , Medicamentos sob Prescrição , Idoso , Humanos , Estados Unidos , Medicamentos Genéricos , Anastrozol , Mesilato de Imatinib , Letrozol , Custos de Medicamentos , Tamoxifeno , Redução de Custos
5.
Physiol Behav ; 268: 114237, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37192686

RESUMO

Two distinct estrogen receptors (ERs) exist, ERα and ERß. Both receptors participate in sexual differentiation of the rat brain and likely participate in the regulation of adult sexual orientation (i.e. partner preference). This last idea was investigated herein by examining males treated with the aromatase inhibitor, letrozole, administered prenatally (0.56 µg/kg G10-22). This treatment usually provokes same-sex preference in 1-2 males per litter. Vehicle-treated males (with female preference) and females in spontaneous proestrus (with male preference) were included as controls. ERα and ERß expression was analyzed by immunohistochemistry in brain areas known to control masculine sexual behavior and partner preference, like the medial preoptic area (MPOA), bed nucleus of the stria terminalis (BNST), medial amygdala (MeA) and ventromedial hypothalamic nucleus (VMH), as well as other brain regions suspected to participate in these processes. In addition, serum levels of estradiol were determined in all male groups. Letrozole-treated male rats that preferred sexually experienced males (LPM) showed over-expressed ERα in the hippocampal cornu Ammonis (CA 1, 3, 4) and dentate gyrus. The LPM group showed up-regulated ERß expression in the CA2 and reticular thalamic nucleus. The levels of estradiol did not differ between the groups. Higher expression of ERs in these males was different than their expression in females, with male sex-preference. This suggests that males with same-sex preference showed a unique brain, this sui generis steroid receptor expression probably participates in the biological underpinnings of sexual preference.


Assuntos
Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Ratos , Animais , Feminino , Masculino , Humanos , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Letrozol/metabolismo , Receptores de Estrogênio/metabolismo , Encéfalo/metabolismo , Área Pré-Óptica/metabolismo , Comportamento Sexual , Estradiol/farmacologia , Estradiol/metabolismo
6.
Reprod Sci ; 29(8): 2272-2281, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35513593

RESUMO

Clomiphene citrate (CC) and letrozole are ovulatory stimulants that, despite high ovulation rates, achieve low pregnancy rates. This study aimed to investigate the in vitro effects of CC and letrozole, alone or in combination with estradiol, on apoptosis in human cumulus cells. We performed a controlled prospective study using primary cumulus cell cultures from patients undergoing in vitro fertilization (n=22). Alpha-inhibin immunocytochemistry was used to assess cell culture purity and morphology. Cell viability was evaluated by MTT assay, cell cycle status by flow cytometry, and Caspase-3, Bax and SOD-2, and S26 gene expression by qPCR. Cells were treated for 24 hours in 5 conditioned media: CC, CC + estradiol, letrozole, letrozole + estradiol and control. None of the treatments affected cell viability, but letrozole reduced the mean percentage of cells in the S phase compared to control (24.79 versus 21.70, p=0.0014). Clomiphene treatment increased mRNA expression of Bax (4 fold) and SOD-2 (2 fold), which was reversed by co-treatment with estradiol. SOD-2 expression increased in cells treated with letrozole compared to control (4 fold), which was also reversed by estradiol. These findings suggest that clomiphene citrate and letrozole do not significantly affect the viability of human cumulus cells. Still, the expression of genes involved in apoptosis was modulated by these drugs alone and in association with estradiol, suggesting that CC and letrozole may have direct effects on cumulus cells beyond their known mechanisms of action.


Assuntos
Fármacos para a Fertilidade Feminina , Infertilidade Feminina , Ciclo Celular , Clomifeno/farmacologia , Clomifeno/uso terapêutico , Células do Cúmulo , Estradiol/farmacologia , Estradiol/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Infertilidade Feminina/tratamento farmacológico , Letrozol/farmacologia , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Indução da Ovulação , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Superóxido Dismutase , Triazóis/farmacologia , Triazóis/uso terapêutico , Proteína X Associada a bcl-2
7.
Int. j. morphol ; 40(4): 1108-1116, 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1405227

RESUMO

SUMMARY: Letrozole is mainly used for the treatment of unexplained infertility, breast cancer and polycystic ovarian syndrome, with secondary use in ovarian stimulation. In cases of unexpected or unknown pregnancy during the use of letrozole, letrozole may cause a teratogenic effect on the fetus. In this reason, in this study, we aimed to determine the effect of letrozole on fetal bone development. In this study, 32 pregnant Wistar albino rats were used. The rats were divided into four groups: Control (saline) and high; 0.3 mg/kg, medium; 0.03 mg/kg, low; 0.003 mg/ kg letrozole. Saline and letrozole were administered in 100 mL solutions by intraperitonaly from day 11 to day 15 of pregnancy. The skeletal system development of fetuses was examined with double skeletal staining, immunohistochemical staining methods and mineral density scanning electron microscopy. A total of 100 fetuses from female rats, 25 in each group, were included in the study. As a result of that, ossification rates were observed to decrease depending on the dose of letrozole in the forelimb limb (scapula, humerus, radius, ulna) and hindlimb (femur, tibia, fibula) limb bones. As a result of the statistical analysis, a statistically significant decrease was found in the ossification rates of all bones between the control group and low, medium, high letrozole groups (p<0.001). Exposure to letrozole during pregnancy adversely affected ossification and bone growth. However, the teratogenic effects of letrozole are unclear. Therefore, it needs to be investigated more extensively.


RESUMEN: Letrozol se usa principalmente para el tratamiento de la infertilidad inexplicable, el cáncer de mama y el síndrome de ovario poliquístico, con estimulación ovárica de uso secundario. En casos de embarazo inesperado o desconocido durante el uso de letrozol, puede causar un efecto teratogénico en el feto. Por esta razón, en este estudio, nuestro objetivo fue determinar el efecto de letrozol en el desarrollo óseo fetal. Se utilizaron 32 ratas albinas Wistar preñadas las cuales se distribuyeron en cuatro grupos: Control (solución salina) y alta; 0,3 mg/kg, medio; 0,03 mg/kg, bajo; 0,003 mg/kg de letrozol. Se administró solución salina y letrozol en soluciones de 100 mL por vía intraperitoneal desde el día 11 hasta el día 15 de la preñez. El desarrollo del sistema esquelético de los fetos se examinó con tinción esquelética doble, métodos de tinción inmunohistoquímica y microscopía electrónica de barrido de densidad mineral. Se incluyeron en el estudio un total de 100 fetos de ratas hembra, 25 en cada grupo. Como resultado, se observó que las tasas de osificación disminuían dependiendo de la dosis de letrozol en los huesos de los miembros torácicos (escápula, húmero, radio, ulna) y de las miembros pélvicos (fémur, tibia, fíbula). Se encontró una disminución estadísticamente significativa en las tasas de osificación de todos los huesos entre el grupo control y los grupos de letrozol bajo, medio y alto (p<0,001). La exposición a letrozol durante la preñez afectó negativamente la osificación y el crecimiento óseo. Sin embargo, los efectos teratogénicos del letrozol no están claros por lo que debe ser investigado más extensamente.


Assuntos
Animais , Feminino , Ratos , Teratogênicos/farmacologia , Desenvolvimento Ósseo/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Letrozol/farmacologia , Antineoplásicos/farmacologia , Osteogênese/efeitos dos fármacos , Coloração e Rotulagem/métodos , Imuno-Histoquímica , Ratos Wistar , Letrozol/efeitos adversos , Antineoplásicos/efeitos adversos
8.
Femina ; 49(10): 636-640, 2021.
Artigo em Português | LILACS | ID: biblio-1358198

RESUMO

Objetivo: Abordar atualizações referentes à terapia medicamentosa para indução da ovulação nas mulheres diagnosticadas com síndrome dos ovários policísticos (SOP). Métodos: Revisão de literatura por meio de levantamento bibliográfico do período de 1975 a 2021, nas bases eletrônicas PubMed, SciELO e MedLine, complementado pela Diretriz Internacional Baseada em Evidências para a Avaliação e Manejo da SOP de 2018 e pelo manual da Febrasgo para SOP. Sete descritores que atendessem à finalidade da pesquisa foram utilizados. Resultados: A literatura aponta atualmente algumas drogas como opção na terapêutica para a indução de ovulação, como metformina, letrozol e citrato de clomifeno, evidenciando que o uso de letrozol isolado e em associação com a metformina apresentaram melhores taxas de ovulação, 71,5% e 75,4%, respectivamente. Conclusão: O uso do letrozol isolado ou combinado com a metformina apresentou os melhores resultados nas taxas de gravidez e ovulação, todavia o tratamento para indução ovulatória deve ser individualizado.(AU)


Objective: To address updates of medicinal therapy for ovulation induction in women diagnosed with polycystic ovary syndrome (PCOS). Methods: Reviewing Literature through a bibliographic survey from 1975 to 2021, on the electronic databases PubMed, SciELO and MedLine, complemented by the International Evidence-Based Guideline for the Evaluation and Management of PCOS 2018 and the Febrasgo guide for PCOS. Seven descriptors that matched to the purpose of the research were applied. Results: Some drugs are currently indicated in the literature as an option for ovulation induction therapy, such as: metformin, letrozole and clomiphene citrate, showing that the use of letrozole alone and in association with metformin had better ovulation rates, 71.5% and 75.4%, respectively. Conclusion: The use of letrozole alone or combined with metformin showed the best results in pregnancy and ovulation rates, however, treatment for ovulatory induction must be individualized.(AU)


Assuntos
Humanos , Feminino , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/tratamento farmacológico , Infertilidade Feminina/tratamento farmacológico , Bases de Dados Bibliográficas , Clomifeno/uso terapêutico , Letrozol/uso terapêutico , Metformina/uso terapêutico
9.
Anim. Reprod. ; 18(2): e20200029, 2021. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-31896

RESUMO

Letrozole is used as a therapeutic agent in reproductive disorders caused by high estrogen levels. Letrozole inhibits cytochrome P450 aromatase and reduces estrogen levels. However, the effects of longterm use on reproductive traits are unknown. The aim of this study was to evaluate the prolonged use of letrozole in the gonads of rodents (Spix's yellow-toothed cavy; Galea spixii). Forty-eight rodents (24 males and 24 females) were randomly divided into the treated and control groups. Letrozole administration started at 15 days of age and continued weekly until 30, 45, 90, and 120 days of age. The body, testis, and ovary weights were analyzed, as well as the morphological progression of spermatogenesis and folliculogenesis. Macroscopically, body weight gain and gonads weight were increased in the letrozole group. Microscopically, the ovaries of treated females showed stratified epithelium and a cellular disorder of the tunica albuginea. In the testes of treated males, the development of seminiferous tubules was delayed and sperm was absent. The collective findings indicate that the prolonged use of letrozole alters secondary sexual characteristics, and causes weight gain, reproductive changes, and male infertility.(AU)


Assuntos
Animais , Roedores/anatomia & histologia , Roedores/fisiologia , Gônadas , Letrozol/administração & dosagem , Letrozol/análise , Comportamento Reprodutivo
10.
Int. j. morphol ; 38(6): 1525-1527, Dec. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1134471

RESUMO

SUMMARY: The study reported the influence of the high and acute dose of Letrozole on the testis morphology in paca (Cuniculus paca), an aromatase inhibitor that reduces the endogenous estrogen, the essential hormone for spermatogenesis. Morphological changes were observed in seminiferous epithelium with germ cells with apoptotic characteristics and presence of vacuoles and nuclei in pycnose.


RESUMEN: El objetivo de este estudio fue analizar la influencia de una dosis alta de Letrozol en la morfología de los testículos de la paca (Cuniculus paca), un inhibidor de la aromatasa que reduce el estrógeno endógeno, la hormona esencial para la espermatogénesis. Se observaron cambios morfológicos en el epitelio seminífero con células germinales con características apoptóticas y la presencia de vacuolas y núcleos en picnosis.


Assuntos
Animais , Masculino , Testículo/efeitos dos fármacos , Inibidores da Aromatase/administração & dosagem , Cuniculidae , Letrozol/administração & dosagem , Epitélio Seminífero/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Imuno-Histoquímica , Orquiectomia , Microscopia Eletrônica de Transmissão , Células Germinativas/efeitos dos fármacos
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