Population Pharmacokinetics of Docetaxel, Paclitaxel, Doxorubicin and Epirubicin in Pregnant Women with Cancer: A Study from the International Network of Cancer, Infertility and Pregnancy (INCIP)

Pregnancy, delivery and neonatal outcomes in women with gastrointestinal system cancer in pregnancy. An evaluation of a population database

OBJECTIVES

Gastrointestinal system (GIS) cancer in pregnancy is a rare disease. Our aim was to evaluate the association between this type of cancer and pregnancy, delivery and neonatal outcomes.

METHODS

We conducted a retrospective population-based cohort study using the Healthcare Cost and Utilization Project, Nation-wide Inpatient Sample (HCUP-NIS). We included all women who delivered or had a maternal death in the US between 2004 and 2014. We compared women with an ICD-9 diagnosis of GIS cancer to those without. Pregnancy, delivery, and neonatal outcomes were compared between the two groups.

RESULTS

A total of 9,096,788 women met inclusion criteria. Amongst them, 194 women (2/100,000) had a diagnosis of GIS cancer during pregnancy. Women with GIS cancer, compared to those without, were more likely to be Caucasian, older than 35 years of age, and to suffer from obesity, chronic hypertension, pregestational diabetes and thyroid disease. The cancer group had a lower rate of spontaneous vaginal delivery (aOR 0.2, 95 % CI 0.13-0.27, p<0.001), and a higher rate of preterm delivery (aOR 1.85, 95 % CI 1.21-2.82, p=0.04), and of maternal complications such as blood transfusion (aOR 24.7, 95 % CI 17.11-35.66, p<0.001), disseminated intravascular coagulation (aOR 14.56, 95 % CI 3.56-59.55, p<0.001), venous thromboembolism (aOR 9.4, 95 % CI 2.3-38.42, p=0.002) and maternal death (aOR 8.02, 95 % CI 2.55-25.34, p<0.001). Neonatal outcomes were comparable between the two groups.

CONCLUSIONS

Women with a diagnosis of GIS cancer in pregnancy have a higher incidence of maternal complications including maternal death, without any differences in neonatal outcomes.

Utility of Physiologically Based Pharmacokinetic Modeling to Investigate the Impact of Physiological Changes of Pregnancy and Cancer on Oncology Drug Pharmacokinetics

BACKGROUND

The treatment of cancer during pregnancy remains challenging with knowledge gaps in drug dosage, safety, and efficacy due to the under-representation of this population in clinical trials. Our aim was to investigate physiological changes reported in both pregnancy and cancer populations into a PBPK modeling framework that allows for a more accurate estimation of PK changes in pregnant patients with cancer.

METHODS

Paclitaxel and docetaxel were selected to validate a population model using clinical data from pregnant patients with cancer. The validated population model was subsequently used to predict the PK of acalabrutinib in pregnant patients with cancer.

RESULTS

The Simcyp pregnancy population model reasonably predicted the PK of docetaxel in pregnant patients with cancer, while a modified model that included a 2.5-fold increase in CYP2C8 abundance, consistent with the increased expression during pregnancy, was needed to reasonably predict the PK of paclitaxel in pregnant patients with cancer. Changes in protein binding levels of patients with cancer had a minimal impact on the predicted clearance of paclitaxel and docetaxel. PBPK modeling predicted approximately 60% lower AUC and Cmax for acalabrutinib in pregnant versus non-pregnant patients with cancer.

CONCLUSIONS

Our results suggest that PBPK modeling is a promising approach to investigate the effects of pregnancy and cancer on the PK of oncology drugs and potentially inform dosing for pregnant patients with cancer. Further evaluation and refinement of the population model are needed for pregnant patients with cancer with additional compounds and clinical PK data.

Predicting Chemotherapy Distribution into Breast Milk for Breastfeeding Women Using a Population Pharmacokinetic Approach

BACKGROUND AND OBJECTIVE

Information on the distribution of chemotherapeutic drugs to breast milk is scarce, and reports are limited to small sample sizes. Anecdotal pharmacokinetic data have typically been acquired from lactating but non-breastfeeding patients who collect breast milk by means of an expression pump, which might not necessarily be representative for a breastfeeding population due to differences in milk production. Consequently, little is known about the variability of chemotherapy distribution to breast milk and the effect of milk production on the distribution of chemotherapy to breast milk. Our aim was to predict chemotherapy distribution to breast milk in a more realistic breastfeeding population and evaluate the effect of discarding breast milk on the potential chemotherapy exposure in infants.

METHODS

We developed a population pharmacokinetic model that described the breast milk production and the chemotherapy distribution to breast milk of a non-breastfeeding population, linked it to plasma pharmacokinetics, and extrapolated this to a breastfeeding population.

RESULTS

We found that cumulative relative infant doses (RID) were higher than 10% for cyclophosphamide and doxorubicin and approximately 1% for paclitaxel. Simulations allowed us to predict the cumulative RID and its variability in the population for patients with different milk productions and the amount of breast milk that has to be discarded to reach cumulative RIDs below 1%, 0.1%, and 0.01%. Discarding 1-2, 3-6, and 0-1 days of breast milk (depending on the milk production of the patient) resulted in cumulative RID below 1% for cyclophosphamide, doxorubicin, and paclitaxel, respectively.

CONCLUSION

Our results may help clinicians to derive the optimal breast milk discarding strategy for an individual patient that wants to breastfeed during chemotherapy and minimize chemotherapy exposure in their infants.

Landscape and Regulatory Perspective on Oncology Drugs in Pregnancy

Cancers affecting pregnant women include breast cancer, melanoma, thyroid cancer, cervical cancer, lymphomas, and leukemias. The medical management of cancer during pregnancy with molecularly targeted oncology drugs remains quite challenging, with knowledge gaps about the drugs' safety and efficacy due to exclusion of pregnant women from cancer clinical trials, discontinuation of individuals who become pregnant during clinical trials, and limited information on appropriate dosing of molecularly targeted oncology drugs during pregnancy. Physiological changes occur during pregnancy and may result in alterations in the absorption, distribution, metabolism, and excretion of drugs used in pregnant women. Physiologically based pharmacokinetic modeling that incorporates physiological changes induced by both the cancer disease state and pregnancy has the potential to inform dosing of molecularly targeted oncology drugs for pregnant women, improve our understanding of the pharmacokinetic changes associated with pregnancy in patients with cancer, facilitate the design of potential studies of molecularly targeted oncology drugs in pregnant women to support dosing recommendations, and provide model-informed pharmacokinetic data to support regulatory decision making.

Patient-Centered Care in the Management of Cancer During Pregnancy

The management of cancer during pregnancy requires a patient-centered, multidisciplinary approach to balance maternal and fetal well-being given the rarity of this clinical scenario and lack of substantial data. Involvement of oncology and nononcology medical specialists and ethical, legal, and psychosocial supports, as needed, is instrumental in navigating the complexities of care for this patient population. Critical periods of fetal development and physiological changes in pregnancy must be considered when planning diagnostic and therapeutic approaches during pregnancy. The complexity of symptom recognition and interventional approaches contributes to diagnostic delays of cancers during pregnancy. Ultrasound and whole-body diffusion-weighted magnetic resonance imaging are safe throughout pregnancy. Surgery can be safely performed throughout pregnancy, with the early second trimester preferred for intra-abdominal surgery. Chemotherapy can be safely administered after 12-14 weeks of gestation until 1-3 weeks before the anticipated delivery. Most targeted and immunotherapeutic agents are contraindicated during pregnancy because of limited data. Pelvic radiation during pregnancy is absolutely contraindicated, while if radiation to the upper body is needed, administration should only be considered early in pregnancy. To ensure that the total cumulative fetal exposure to ionizing radiation does not exceed 100 mGy, early inclusion of the radiology team in the care plan is required. Closer prenatal monitoring is recommended for maternal and fetal treatment-related toxicities. Delivery before 37 weeks of gestation should be avoided if possible, and vaginal delivery is preferred unless obstetrically indicated or specific clinical scenarios. Postpartum, breastfeeding should be discussed, and the neonate should receive blood work to assess for acute toxicities with follow-up arranged for long-term monitoring.

Optimizing Therapeutic Drug Monitoring in Pregnant Women: A Critical Literature Review

BACKGROUND

More than 90% of pregnant women take at least one drug during pregnancy. Drug dose adjustments during pregnancy are sometimes necessary due to various pregnancy-induced physiological alterations frequently associated with lower plasma concentrations. However, the clinical relevance or benefits of therapeutic drug monitoring (TDM) in pregnant women have not been specifically studied. Clinical pharmacokinetic studies in pregnant women are incredibly challenging for many reasons. Despite this, regulatory agencies have made efforts to encourage the inclusion of this population in clinical trials to achieve more information on the pharmacotherapy of pregnant women. This review aims to provide support for TDM recommendations and dose adjustments in pregnant women.

METHODS

The search was conducted after a predetermined strategy on PubMed and Scopus databases using the MeSH term "pregnancy" alongside other terms such as "Pregnancy and dose adjustment," "Pregnancy and therapeutic drug monitoring," "Pregnancy and PBPK," "Pregnancy and pharmacokinetics," and "Pregnancy and physiological changes."

RESULTS

The main information on TDM in pregnant women is available for antiepileptics, antipsychotics, antidepressants, antibiotics, antimalarials, and oncologic and immunosuppressive drugs.

CONCLUSIONS

More data are needed to support informed benefit-risk decision making for the administration of drugs to pregnant women. TDM and/or pharmacokinetic studies could ensure that pregnant women receive an adequate dosage of an active drug. Mechanistic modeling approaches potentially could increase our knowledge about the pharmacotherapy of this special population, and they could be used to better design dosage regimens.

Population pharmacokinetics of doxorubicin: A systematic review

Because of the high interindividual pharmacokinetic variability, several population pharmacokinetic (PopPK) models of doxorubicin (DOX) were developed to characterize factors influencing such variability. However, significant predictors for DOX pharmacokinetics identified using PopPK models varied across studies. Thus, this review aims to summarize PopPK models of DOX and its metabolites (if any) as well as significant covariates influencing DOX (and its metabolites) pharmacokinetic variability. A systematic search from PubMed, CINAHL Complete, Science Direct, and SCOPUS databases identified 503 studies. Of these, 16 studies met the inclusion criteria and were included in this review. DOX pharmacokinetics was described with two- or three-compartment models. Most studies found a significant increase in DOX clearance with an increase in body surface area from the median value of 1.8 m² . Moreover, this review identified that while a 10-year increase in patient age resulted in a decrease in DOX clearance in adults and the elderly, younger children had lower DOX clearance compared to older children. Further, low DOX exposure was observed in pregnant women, and thus dosage adjustment is required. Concerning model applicability, predictive performance assessment of these published models should be performed before implementing such models in clinical practice.

Weekly Paclitaxel Administered During a Twin Pregnancy for Recurrent Breast Cancer: Case Report and Review of the Literature

Although cancer treatment during single pregnancy has been standardized, how to manage cancer diagnosed during a multiple gestation is still unclear. Chemotherapy during pregnancy has shown to be safe, however, there are reports of increased risks of fetal complications such as intrauterine growth restriction and preterm birth. Also, how to best adjust this to the pharmacokinetic characteristics of a twin gestation has yet to be fully investigated. We report the case of an IVF twin pregnancy with a diagnosis of breast cancer recurrence shortly after conception, and how the pregnancy was managed to obtain optimal obstetric, maternal/oncological, and fetal outcomes.

Construction and Biological Evaluation of Multiple Modification Hollow Mesoporous Silicone Doxorubicin Nanodrug Delivery System

The combination of functionalized nanoparticles and chemotherapy drugs can effectively target tumor tissue, which can improve efficacy and reduce toxicity. In this article, pPeptide-PDA@HMONs-DOX nanoparticles (phosphopeptide-modified polydopamine encapsulates doxorubicin-loaded hollow mesoporous organosilica nanoparticles) were constructed that based on multiple modification hollow mesoporous organosilica nanoparticles (HMONs). The pPeptide-PDA@HMONs-DOX nanoparticles retain the biological functions of phosphorylated peptide while exhibiting biological safety that are suitable for effective drug delivery and stimulus responsive release. The degradation behaviors showed that pPeptide-PDA@HMONs-DOX has dual-responsive to drug release characteristics of pH and glutathione (GSH). In addition, the prepared pPeptide-PDA@HMONs-DOX nanoparticles have good biological safety, and their anti-tumor efficacy was significantly better than doxorubicin (DOX). This provided new research ideas for the construction of targeted nanodrug delivery systems based on mesoporous silicon. Scheme 1 The preparation of pPeptide-PDA@HMONs-DOX and the process of drug release under multiple responses. (A) Schematic diagram of the synthesis process of pPeptide-PDA@HMONs-DOX. (B) The process in which nanoparticles enter the cell and decompose and release DOX in response to pH and GSH.

Breast cancer during pregnancy: epidemiology, phenotypes, presentation during pregnancy and therapeutic modalities

Although it is uncommon in general, breast cancer is the most commonly diagnosed cancer during pregnancy. While treatment for pregnant patients should adhere to treatment guidelines for non-pregnant patients, there exist specific considerations concerning diagnosis, staging, oncological treatment, and obstetrical care. Imaging and staging are preferably performed using breast ultrasound and mammography. Other ionizing radiation imaging modalities, including computed tomography (CT) and Positron Emission Tomography/ Computed Tomography (PET/CT), can be selectively performed when the estimated benefit for the mother outweighs the risks to the foetus, e.g., when the results will change clinical management. MRI is appropriate to stage for distant disease on the indication. Breast cancer during pregnancy is less often hormone receptor-positive and more frequently triple-negative breast cancer compared to age-matched controls. The basic principle is that women should receive state-of-the-art oncological treatment without delay if possible and that the pregnancy should be maintained as long as possible. Treatment strategy should be multidisciplinary defined, carefully weighing the selection, sequence, and timing of treatment modalities depending on patient-, tumour-, and pregnancy-related characteristics, as well as patient preferences. Initiating cancer treatment during pregnancy often decreases the risks of early delivery and prematurity. Breast cancer surgery is possible during all trimesters. Radiotherapy is possible during pregnancy in the first half of pregnancy. Chemotherapy can be safely administered starting from 12 weeks of gestational age, but endocrine and HER2 targeted therapy are contraindicated throughout the whole pregnancy. Importantly, foetal growth should be monitored and long-term follow-up of the children is encouraged in dedicated centres.

Outcome of breast cancer patients treated with chemotherapy during pregnancy compared with non-pregnant controls

BACKGROUND

A diagnosis of breast cancer during pregnancy (PrBC) does not impact prognosis if standard treatment is offered. However, caution is warranted as gestational changes in pharmacokinetics may lead to reduced chemotherapy concentration.

METHODS

Survival of PrBC patients treated with chemotherapy during pregnancy was compared to non-pregnant breast cancer patients treated with chemotherapy, diagnosed after 2000, excluding patients older than 45 years or with a postpartum diagnosis. The data was registered in two multicenter registries (the International Network of Cancer, Infertility and Pregnancy and the German Breast Group). Cox proportional hazards regression was used to compare disease-free (DFS) and overall survival (OS) between both groups, adjusting for age, stage, grade, hormone receptor status, human epidermal growth factor 2 status and histology, weighted by propensity scoring to account for the differences in baseline characteristics between pregnant patients and controls.

RESULTS

In total, 662 pregnant and 2081 non-pregnant patients were selected. Pregnant patients were more likely to have stage II breast cancer (60.1% vs 56.1%, p = 0.035), grade 3 tumors (74.0% vs 62.2%, p < 0.001), hormone receptor-negative tumors (48.4% vs 34.0%, p < 0.001) or triple-negative breast cancer (38.9% vs 26.9%, p < 0.001). Median follow-up was 66 months. In multivariable analysis, DFS and OS were comparable for pregnant and non-pregnant patients (DFS: HR 1.02, 95% CI 0.82-1.27, p = 0.83; OS: HR 1.08, 95% CI 0.81-1.45, p = 0.59).

CONCLUSION

Outcome of women with breast cancer treated with chemotherapy during pregnancy is comparable to young non-pregnant women. These results support chemotherapy for PrBC when indicated.