Phase I and Pharmacokinetic Study of Pemetrexed Administered Every 3 Weeks to Advanced Cancer Patients With Normal and Impaired Renal Function

Disease control in patients with non-small cell lung cancer using pemetrexed: Investigating the best treatment strategy

BACKGROUND

Pemetrexed (PEM) is the primary chemotherapy for non-small cell lung cancer (NSCLC), showing potential for long-term disease stability in certain cases. However, studies examining disease control with PEM therapy are lacking. This study aimed to pinpoint clinical traits in patients with NSCLC responding well to PEM therapy, predict factors influencing disease control, and suggest optimal treatment approaches.

METHODS

A retrospective analysis of patients with NSCLC treated with PEM was performed to compare patients who achieved disease control after treatment with those who did not.

RESULTS

Of 73 patients, 56 (76.7%) achieved disease control with PEM therapy. In the disease control group, a significantly higher proportion of patients exhibited good performance status (PS) and received PEM doses without reduction after the second cycle. Multivariate analysis identified bevacizumab (Bev) noncompliance, PEM dose reduction, and thyroid transcription factor-1 (TTF-1) negativity as significant independent risk factors for disease progression during PEM therapy. Additionally, overall survival was significantly longer in the disease control group (p < 0.001).

CONCLUSIONS

Our findings indicated that maintaining the dose of PEM after the second treatment cycle in patients with NSCLC, along with concurrent use of Bev and the presence of TTF-1 positivity, could enhance disease control rates and extend survival.

Renal Immune-related Adverse Event of Pembrolizumab Masked by Pemetrexed

A Japanese woman in her 60s developed a kidney injury 9 weeks after treatment with pemetrexed, carboplatin, and pembrolizumab for stage IV lung adenocarcinoma. A renal biopsy showed chronic tubulointerstitial damage with minimal focal interstitial inflammation, consistent with pemetrexed-induced nephropathy; thus, pemetrexed was withdrawn. However, the kidney injury continued to worsen. A repeated biopsy showed severe acute tubulointerstitial nephritis, suggestive of a pembrolizumab-induced immune-related adverse event (irAE). The worsening after pemetrexed discontinuation suggested that the irAE had already begun, as the first biopsy showed focal inflammation. This case suggests thatcombining immune checkpoints and chemotherapy requires considering concurrent drug-induced nephrotoxicity.

Chapter 3: Management of kidney injury caused by cancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

Cisplatin should be administered with diuretics and Magnesium supplementation under adequate hydration to avoid renal impairment. Patients should be evaluated for eGFR (estimated glomerular filtration rate) during the treatment with pemetrexed, as kidney injury has been reported. Pemetrexed should be administered with caution in patients with a CCr (creatinine clearance) < 45 mL/min. Mesna is used to prevent hemorrhagic cystitis in patients receiving ifosfamide. Febuxostat is effective in avoiding hyperuricemia induced by TLS (tumor lysis syndrome). Preventative rasburicase is recommended in high-risk cases of TLS. Thrombotic microangiopathy could be triggered by anticancer drugs and there is no evidence of efficacy of plasma exchange therapy. When proteinuria occurs during treatment with anti-angiogenic agents or multi-kinase inhibitors, dose reductions or interruptions based on grading should be considered. Grade 3 proteinuria and renal dysfunction require urgent intervention, including drug interruption or withdrawal, and referral to a nephrologist should be considered. The first-line drugs used for blood pressure elevation due to anti-angiogenic agents are ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin receptor blockers). The protein binding of drugs and their pharmacokinetics are considerably altered in patients with hypoalbuminemia. The clearance of rituximab is increased in patients with proteinuria, and the correlation with urinary IgG suggests similar pharmacokinetic changes when using other antibody drugs. AIN (acute interstitial nephritis) is the most common cause of ICI (immune checkpoint inhibitor)-related kidney injury that is often treated with steroids. The need for renal biopsy in patients with kidney injury that occurs during treatment with ICI remains controversial.

Folate, folic acid, and chemotherapy-induced toxicities: a systematic literature review

Folate metabolism is a target for various chemotherapeutic drugs. Folate and its synthetic variant folic acid are B-vitamins. To what extent these vitamins impact treatment tolerance in patients with cancer remains unclear. A systematic literature review was conducted on intake and status of folate and folic acid in relation to chemotherapy-induced toxicities in children and adults with cancer. A total of 6,231 publications were identified, of which 40 publications met the inclusion criteria. In 12 out of 22 studies focusing on antifolates, a deficient folate status and lower folate and folic acid intake were associated with a higher risk of toxicities. In 8 out of 14 studies focusing on fluoropyrimidine treatments, a higher folate status and intake were associated with a higher risk of toxicities. These findings might explain interindividual differences in treatment tolerance and highlight the importance of evaluating nutritional status in oncology care.

Predicting the Effect of Renal Function on Systemic Clearance: Is a simple scaling method sufficient?

PURPOSE

To employ a simple scaling method to predict systemic or oral clearance for drugs that are primarily renally cleared knowing the fraction eliminated in urine (f_e) and a patient's renal function relative to healthy controls (S_GFR).

METHODS

Observations evaluating drug clearance as a function of creatinine clearance for renally cleared drugs (f_e >0.3) were obtained from literature sources. The analysis comprised of 82 unique drugs from 124 studies including 31 drugs with replicate studies. A simple scaler for renal function was employed and compared to the linear regression of available data. For drugs in which replicate studies were available, the ability of the linear regression (Cl vs Cl_CR) from one pharmacokinetic study was used to predict observations from an assigned replicate and compared to the scaling approach.

RESULTS

For patients categorized as severe kidney disease (Cl_CR fixed at 20 ml/min), the scalar tended to over predict some observations, but 92% of the predictions were within 50 - 200% of the observed data. For drugs with available replicates, the scalar was as good or better in predicting the influence of Cl_CR on systemic clearance from a separate study when comparing against the linear regression approach.

CONCLUSION

A scaling approach to account for alterations in drug clearance appears to have its advantages and represents a simple and generalizable method for guiding dose adjustments in patients with decreased renal function for drugs that are renally cleared (f_e >0.3). In addition to its use in clinical practice, validation of this approach may have implications in facilitating more efficient drug development processes for designing dose-adjusted pharmacokinetic studies in patients with renal disease.

Anticancer drug therapy for patients with renal dysfunction

Anticancer drug therapy for cancer is developing rapidly, including molecular-targeted drugs and immune checkpoint inhibitors that are used in clinical settings in addition to conventional cytotoxic drugs. In daily clinical practice, clinicians sometimes encounter situations in which the effects of these chemotherapeutic agents are considered unacceptable in high-risk patients with liver or renal dysfunction, those undergoing dialysis and older adults. There is no clear evidence regarding anticancer drugs administration to patients with renal dysfunction. However, there are indications for dose setting based on the theory of the renal function responsible for drug excretion and past administration experience. This review outlines anticancer drugs' administration in patients with renal dysfunction.

Renal function-based versus standard dosing of pemetrexed: a randomized controlled trial

PURPOSE

Pemetrexed is a chemotherapeutic drug in the treatment of non-small cell lung cancer and mesothelioma. Optimized dosing of pemetrexed based on renal function instead of body surface area (BSA) is hypothesized to reduce pharmacokinetic variability in systemic exposure and could therefore improve treatment outcomes. The aim of this study is to compare optimized dosing to standard BSA-based dosing.

METHODS

A multicenter randomized (1:1) controlled trial was performed to assess superiority of optimized dosing versus BSA-based dosing in patients who were eligible for pemetrexed-based chemotherapy. The individual exposure to pemetrexed in terms of area under the concentration-time curve (AUC) was determined. The fraction of patients attaining to a predefined typical target AUC (164 mg × h/L ± 25%) was calculated.

RESULTS

A total of 81 patients were included. Target attainment was not statistically significant different between both arms (89% vs. 84% (p = 0.505)). The AUC of pemetrexed was similar between the optimized dosing arm (n = 37) and the standard of care arm (n = 44) (155 mg × h/L vs 160 mg × h/L (p = 0.436).

CONCLUSION

We could not show superiority of optimized dosing of pemetrexed in patients with an adequate renal function does not show added value on the attainment of a pharmacokinetic endpoint, safety, nor QoL compared to standard of care dosing.

CLINICAL TRIAL NUMBER

Clinicaltrials.gov identifier: NCT03655821.

Mechanisms, Management and Prevention of Pemetrexed-Related Toxicity

Pemetrexed is a cytostatic antifolate drug and a cornerstone in the treatment of lung cancer. Although generally well tolerated, a substantial part of the patient population experiences dose-limiting or even treatment-limiting toxicities. These include mucositis, skin problems, fatigue, renal toxicity, and neutropenia. Several studies confirmed that pemetrexed pharmacokinetics can serve as a prognostic factor for the development of toxicity, especially for neutropenia. Preventing and managing toxicity of pemetrexed can help to ensure durable treatment. Several evidence-based strategies are already implemented in clinical care. With the introduction of standard vitamin supplementation and dexamethasone, the incidence of hematological toxicity and skin reactions substantially decreased. In the case of high risk for toxicity, granulocyte colony-stimulating factor can be used to prevent severe hematological toxicity. Moreover, high-dose folinic acid can resolve severe pemetrexed-induced toxicity. There are several experimental options to prevent or manage pemetrexed-related toxicity, such as the use of standard folinic acid, hemodialysis, antidotes such as thymidine, hypoxanthine, and glucarpidase, and the use of therapeutic drug monitoring. These strategies still need clinical evaluation before implementation, but could enable treatment with pemetrexed for patients who are at risk for toxicity, such as in renal impairment.

Hyperhydration with cisplatin does not influence pemetrexed exposure

Pemetrexed is a cytotoxic drug for first‐line treatment of lung cancer. It is often combined with other anticancer drugs such as cisplatin or carboplatin. In clinical practice, hyperhydration regimens are applied to overcome cisplatin‐related nephrotoxicity. As pemetrexed is almost completely eliminated from the body by the kidneys, hyperhydration can result in augmented clearance. Furthermore, administration of large quantities of fluid may increase the volume of distribution of pemetrexed. Pharmacokinetics and, thus, efficacy and toxicity may be influenced by hyperhydration. This has not yet been properly studied. We performed a population pharmacokinetic analysis to assess hyperhydration as a covariate for pemetrexed clearance and for volume of distribution A relevant change was defined as >25% increase in clearance or volume of distribution. In our extensive dataset of 133 individuals, we found that hyperhydration did not significantly or relevantly explain variability in pemetrexed clearance (unchanged, P = .196) or volume of distribution (+7% change, P = .002), despite a power of >99% to detect a relevant change. Therefore, dose adjustments of pemetrexed are not required during hyperhydration with cisplatin.

Toxicity of pemetrexed during renal impairment explained-Implications for safe treatment

Pemetrexed is an important component of first line treatment in patients with non-squamous non-small cell lung cancer. However, a limitation is the contraindication in patients with renal impairment due to hematological toxicity. Currently, it is unknown how to safely dose pemetrexed in these patients. The aim of our study was to elucidate the relationship between pemetrexed exposure and toxicity to support the development of a safe dosing regimen in patients with renal impairment. A population pharmacokinetic/pharmacodynamic analysis was performed based on phase II study results in three patients with renal dysfunction, supplemented with data from 106 patients in early clinical studies. Findings were externally validated with data of different pemetrexed dosing regimens. Alternative dosing regimens were evaluated using the developed model. We found that pemetrexed toxicity was driven by the time above a toxicity threshold concentration. The threshold for vitamin-supplemented patients was 0.110 mg/mL (95% CI: 0.092-0.146 mg/mL). It was observed that in patients with renal impairment (estimated glomerular filtration rate [eGFR]: <45 mL/min) the approved dose of 500 mg/m² would yield a high probability of severe neutropenia in the range of 51.0% to 92.6%. A pemetrexed dose of 20 mg for patients (eGFR: 20 mL/min) is shown to be neutropenic-equivalent to the approved dose in patients with adequate renal function (eGFR: 90 mL/min), but would result in an approximately 13-fold lower area under the concentration-time curve. The pemetrexed exposure-toxicity relationship is explained by a toxicity threshold and substantially different from previously thought. Without prophylaxis for toxicity, it is unlikely that a therapeutic dose can be safely administered to patients with renal impairment.

Rethinking the Application of Pemetrexed for Patients with Renal Impairment: A Pharmacokinetic Analysis

Background

Pemetrexed is used for the treatment for non-small cell lung cancer and mesothelioma. Patients with renal impairment are withheld treatment with this drug as it is unknown what dose is well tolerated in this population.

Objective

The purpose of our study was to investigate the pharmacokinetics (PK) of pemetrexed in patients with renal impairment.

Methods

A population PK analysis of pemetrexed was performed using non-linear mixed-effects modelling with phase I data obtained from the manufacturer. Additionally, the impact of renal function on pemetrexed PK was assessed with a simulation study using the developed PK model and a previously developed PK model lacking the phase I data.

Results

The dataset included 548 paired observations of 47 patients, with a wide range of estimated glomerular filtration rates (eGFR; 14.4–145.6 mL/min). Pemetrexed PK were best described by a three-compartment model with eGFR (calculated using the Chronic Kidney Disease–Epidemiology Collaboration [CKD-EPI] formula) as a linear covariate on renal pemetrexed clearance. Using the developed model, we found that renal clearance accounts for up to 84% (95% confidence interval 69–98%) of total pemetrexed clearance, whereas the manufacturer previously reported a 50% contribution of renal clearance.

Conclusion

Renal function is more important for the clearance of pemetrexed than previously thought and this should be taken into account in patients with renal impairment. Furthermore, a third compartment may contribute to prolonged exposure to pemetrexed during drug washout.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-020-00972-1.

Haematological toxicity of pemetrexed in patients with metastatic non-squamous non-small cell carcinoma of lung with third-space fluid

BACKGROUND

Pemetrexed was approved by United States Food and Drug Administration (US FDA) in combination with platinum for the treatment of advanced non-squamous non-small cell lung carcinoma (NSCLC) and malignant mesothelioma. Due to the structural similarity with methotrexate, there has been concern about the accumulation of pemetrexed in third space fluid that may result in increased toxicity. Previous small-scale studies have yet to conclusively prove this association.

METHODS

This was a retrospective single-center cohort study conducted in Queen Mary Hospital in Hong Kong. The study included 329 patients with advanced stage non-squamous NSCLC that received first line pemetrexed and platinum. Patients who had non-evacuated third-space fluid, evacuated third-space fluid and without third-space fluid were compared. The primary endpoint was the occurrence of hematological toxicity.

RESULTS

The presence of non-evacuated third-space fluid was shown to be associated with significantly more hematological toxicities, namely grade 3 or above hematological toxicities [Odd ratio (OR) = 2.450, p = 0.002], postponement of chemotherapy (OR = 3.837, p = 0.000) and need for dose adjustment (OR = 2.436, p = 0.022) when compared with those without third-space fluid. For patients with evacuated third-space fluid, these adverse effects were nullified.

CONCLUSIONS

Presence of non-evacuated third-space fluid in patients with advanced non-squamous NSCLC predispose patients to significant hematological toxicity when pemetrexed and platinum chemotherapy is used. Evacuation of third-space fluid should be considered before starting pemetrexed and platinum doublet.

Long-term exposure to pemetrexed induces chronic renal dysfunction in patients with advanced and recurrent non-squamous cell lung cancer: a retrospective study

Background

Pemetrexed (PEM) is administered over a long term to patients with non-squamous cell lung cancer as a maintenance therapy after platinum combination induction chemotherapy. Although decreased renal function owing to long-term PEM exposure has been reported, changes in the renal function of individual patients have not been reported. This study aimed to evaluate serum creatinine (Scr) in individual patients over time and determine whether long-term PEM exposure contributed to increased Scr.

Methods

A retrospective study was performed using 90 non-squamous cell lung cancer patients, who had received maintenance therapy with PEM ± bevacizumab (BEV) after carboplatin + PEM ± BEV therapy at the Sapporo Minami-Sanjo Hospital from February 2012 to February 2019. Using Scr at the start of induction chemotherapy as the baseline, we calculated the correlation coefficient (r) of the rate of Scr change in an individual patient and the number of treatment courses to divide patients into two groups for comparison: patients with + 0.4 < r ≦ + 1.0 and an observed positive correlation (the r+0.4< group), and patients with − 1.0 ≦ r ≦ + 0.4 and no observed positive correlation (the r+0.4≧ group).

Results

Statistically significant differences between the r+0.4< group and the r+0.4≧ group were observed for the following parameters: the median cumulative dose of PEM (interquartile range) [9100 (6365, 12,260) mg/body vs. 5600 (4140, 7440) mg/body, P < 0.01]; the number of patients taking nonsteroidal anti-inflammatory drugs at the start of treatment [15 patients (31%) vs. 3 patients (7%), P < 0.01]; and the median number of treatment courses starting from induction chemotherapy [11 (8, 14) courses vs. 8 (6, 11) courses, P < 0.01]. Next, the results of univariate and multivariate analyses demonstrated that the cumulative dose of PEM (≧ 7000 mg/body vs < 7000 mg/body, OR 2.40; 95% CI, 1.22–4.75, P = 0.01) was an independent explanatory variable of the r+0.4< group.

Conclusions

Long-term PEM exposure may induce chronic renal dysfunction. Hence, maintaining kidney function during PEM treatment by reducing the use of combination drugs and the risk of other renal dysfunctions, such as dehydration, may help patients continue therapy and contribute to their long-term survival.

Better survival in impaired renal function patients with metastatic non-small cell lung cancer treated by cisplatin-pemetrexed

PURPOSE

Cisplatin-pemetrexed is the first-line chemotherapy for advanced, metastatic non-squamous non-small cell lung cancer (NSCLC), but the risk of kidney toxicity limits the therapeutic schedule. We performed a retrospective study of patient survival at 1 year and glomerular filtration rate (GFR) outcomes in cisplatin-pemetrexed-treated NSCLC patients.

METHODS

Patients (P) treated for NSCLC between 2008 and 2014 were divided into two groups according to GFR at diagnosis: G1 (GFR ≥ 90 mL/min/1.73 m²) and G2 (GFR between 60 and 89 mL/min/1.73 m²). GFR were compared in the two groups at 3 and 12 months. The following statistical methods were used: multivariate generalized estimating equation model for GFR outcome, Kaplan-Meier method for patient survival rate, and Cox model for analysing survival criteria.

RESULTS

A total of 112 patients were included in the study (G1 = 87 P, G2 = 25 P). At 12 months, mean GFR significantly decreased by 28.4 mL/min/1.73 m² (- 22.3%, p = 0.001) in G1 and. 13.8 mL/min/1.73 m² (- 17.2%, p = 0.001) in G2. Median patient survival was 9.6 months (1.1-52.4) in G1 and 19.7 months (3.7-56.9) in G2. A better overall survival was significantly correlated with GFR between 60 and 89 mL/min/1.73 m² at diagnosis (p = 0.04), and higher cumulated doses of pemetrexed (p = 0.003) and cisplatin (p = 0.001).

CONCLUSION

The better survival rate in G2 and its correlation with pemetrexed and cisplatin treatments suggest that, until other therapeutic choices become available, a cautious increase in dosage could be investigated as a way to improve poor prognoses.

Dose recommendations for anticancer drugs in patients with renal or hepatic impairment

Renal or hepatic impairment is a common comorbidity for patients with cancer either because of the disease itself, toxicity of previous anticancer treatments, or because of other factors affecting organ function, such as increased age. Because renal and hepatic function are among the main determinants of drug exposure, the pharmacokinetic profile might be altered for patients with cancer who have renal or hepatic impairment, necessitating dose adjustments. Most anticancer drugs are dosed near their maximum tolerated dose and are characterised by a narrow therapeutic index. Consequently, selecting an adequate dose for patients who have either hepatic or renal impairment, or both, is challenging and definitive recommendations on dose adjustments are scarce. In this Review, we discuss the effect of renal and hepatic impairment on the pharmacokinetics of anticancer drugs. To guide clinicians in selecting appropriate dose adjustments, information from available drug labels and from the published literature were combined to provide a practical set of recommendations for dose adjustments of 160 anticancer drugs for patients with hepatic and renal impairment.

Pemetrexed in Recurrent or Progressive Central Nervous System Lymphoma: A Phase I Multicenter Clinical Trial

LESSONS LEARNED

The findings from this study using monotherapy with pemetrexed in a pretreated patient population are, overall, encouraging. Unlike high-dose methotrexate, which requires several days of inpatient hospitalization, pemetrexed is relatively easy to administer in the outpatient setting and remains a viable treatment option in this patient population. The maximum tolerated dose of pemetrexed administered (900 mg/m² every 2 weeks) was generally well tolerated and showed activity in patients with relapsed or refractory CNSL.

BACKGROUND

There is currently no standard salvage treatment for patients with relapsed/refractory central nervous system (CNS) lymphoma (CNSL). We report the results of a phase I study of pemetrexed, an antifolate drug with broader activity than methotrexate (MTX). We provide the safety, tolerability, and maximum tolerated dose (MTD) of pemetrexed in patients with recurrent CNSL.

METHODS

Through October 2015, 17 patients with relapsed/refractory CNSL received pemetrexed every 2 weeks with the first cohort receiving 600 mg/m² and dose escalation in increments of 300 mg/m² to a maximum of 1,200 mg/m² . Three patients were to enroll at each dose level with expansion to six patients in the event of dose-limiting toxicity. Patients with both primary CNS lymphoma (PCNSL) and secondary CNS lymphoma (SCNSL) could be enrolled.

RESULTS

Seventeen patients were evaluable with a median age of 63.7 years. Main adverse events included fatigue (82.4%), anemia (82.4%), and neutropenia (70.6%). The MTD was established at 900 mg/m² . Dose-limiting toxicities were recorded in one patient in the 600 mg/m² cohort and in two patients in the 1,200 mg/m² cohort. Fourteen patients were evaluable for response assessment; 21.4% achieved a complete response, 35.7% had a partial response, 14.3% had stable disease, and 28.6% had progressive disease. The median progression-free survival was 4.2 months. The median overall survival was 44.5 months. In the original study protocol, the plan was to add an expansion cohort of six patients at MTD level. However, the first phase of the study was characterized by slow recruitment. Therefore, after achieving the primary objective of the study and establishing the MTD, the investigators decided to amend the protocol and to close the study.

CONCLUSION

Pemetrexed administered at 900 mg/m² every 2 weeks exhibits single-agent activity in patients with recurrent CNSL; it is well tolerated, and side effects are manageable.

Cumulative pemetrexed dose increases the risk of nephrotoxicity

INTRODUCTION

Pemetrexed is a pharmacotherapeutic cornerstone in the treatment of non-small cell lung cancer. As it is primarily eliminated by renal excretion, adequate renal function is essential to prevent toxic exposure. There is growing evidence for the nephrotoxic potential of pemetrexed, which even becomes a greater issue now combined immuno-chemotherapy prolongs survival. Therefore, the aim of this study was to describe the incidence of nephrotoxicity and related treatment consequences during pemetrexed-based treatment.

METHODS

A retrospective cohort study was conducted in the Jeroen Bosch Hospital, Den Bosch, the Netherlands. All patients that received at least 1 cycle of pemetrexed based therapy were included in the dataset. The primary outcome was defined as a ≥25 % reduction in eGFR. Additionally, the treatment consequences of decreased renal function were assessed. Logistic regression was used to identify risk factors for nephrotoxicity during treatment with pemetrexed.

RESULTS

Of the 359 patients included in this analysis, 21 % patients had a clinically relevant decline in renal function after treatment and 8.1 % of patients discontinued treatment due to nephrotoxicity. Cumulative dose (≥10 cycles of pemetrexed based therapy) was identified as a risk factor for the primary outcome measure (adjusted OR 5.66 (CI 1.73-18.54)).

CONCLUSION

This study shows that patients on pemetrexed-based treatment are at risk of developing renal impairment. Risk significantly increases with prolonged treatment. Renal impairment is expected to become an even greater issue now that pemetrexed-based immuno-chemotherapy results in longer survival and thus longer treatment duration.

Clinical factors associated with treatment toxicity of pemetrexed plus platinum in elderly patients with non-small cell lung cancer

BACKGROUND

This study was to explore the clinical factors associated with treatment toxicities of pemetrexed plus platinum in elderly patients with non-small cell lung cancer (NSCLC).

METHODS

Chemo-naive patients aged ≥ 70 with advanced NSCLC treated with pemetrexed plus platinum were included. Medical records were reviewed and clinical data, including age, gender, smoking status, comorbidities, EGFR mutation status, chemotherapy regimens, previous use of epidermal growth factor receptor-tyrosine kinase inhibitors, treatment-related hematologic, renal, and hepatic toxicities, and treatment responses, were analyzed. Comorbidity conditions were evaluated by using the Simplified Comorbidity Score (SCS) and Charlson Comorbidity Index Score (CCIS).

RESULTS

A total of 144 patients were included. In the univariate analysis, patients with SCS >9 (p = 0.006) and cigarette smoking (p = 0.028) were associated with a significantly higher rate of grade 3/4 neutropenia than their counterpart. Carboplatin use was associated with a higher rate of grade 3/4 thrombocytopenia than cisplatin use (p = 0.028). In the multivariate analysis, SCS >9 was associated with a significantly higher risk of anemia of any grade (odds ratio [OR]: 2.72, 95% confidence interval [CI]: 1.09-6.77). Carboplatin use was associated a higher risk of any grade (OR: 4.61, 95% CI: 1.07-19.90) and grade 3/4 thrombocytopenia (OR: 7.37, 95% CI: 1.36-39.92). No clinical factors were found to be associated with hepatic and renal toxicities.

CONCLUSION

High SCS and carboplatin use were associated with hematological toxicities with pemetrexed plus platinum use in elderly patients with NSCLC.

Pemetrexed exposure predicts toxicity in advanced non-small-cell lung cancer: A prospective cohort study

BACKGROUND

We explored whether total exposure to pemetrexed predicts effectiveness and toxicity in advanced non-small-cell lung cancer (NSCLC). Furthermore, we investigated alternative dosing schedules.

METHODS

In this prospective cohort study, patients with advanced NSCLC receiving first- or second-line pemetrexed(/platinum) were enrolled. Plasma sampling was performed weekly (cyclePK) and within 24 h (24hPK) after pemetrexed administration. With population pharmacokinetic/pharmacodynamic modelling, total exposure to pemetrexed during cycle 1 (area under the curve during chemotherapy cycle 1 [AUC₁]) was estimated and related to progression-free survival (PFS)/overall survival (OS). We compared mean AUC₁ (mg·h/L) in patients with and without severe chemotherapy-related adverse events (AEs) during total treatment. Second, different dosing schedules were simulated to minimise the estimated variability (coefficient of variation [CV]) of AUC.

RESULTS

For 106 of 165 patients, concentrations of pemetrexed were quantified (24hPK, n = 15; cyclePK, n = 106). After adjusting for prognostic factors, sex, disease stage and World Health Organisation performance score, AUC₁ did not predict PFS/OS in treatment-naive patients (n = 95) (OS, hazard ratio [HR] = 1.05, 95% confidence interval [CI]: 1.00-1.11; PFS, HR = 1.03, 95% CI: 0.98-1.08). Patients with severe chemotherapy-related AEs (n = 55) had significantly higher AUC₁ values than patients without them (n = 51) (226 ± 53 vs 190 ± 31, p < 0.001). Compared with body surface area-based dosing (CV: 22.5%), simulation of estimated glomerular filtration rate (eGFR)-based dosing (CV 18.5%) and fixed dose of 900 mg with 25% dose reduction, if the eGFR<60 mL/min (CV: 19.1%), resulted in less interindividual variability of AUC.

CONCLUSIONS

Higher exposure to pemetrexed does not increase PFS/OS but is significantly associated with increased occurrence of severe toxicity. Our findings suggest that fixed dosing reduces interpatient pharmacokinetic variability and thereby might prevent toxicity, while preserving effectiveness.

A Pilot Phase 1 Study of Intrathecal Pemetrexed for Refractory Leptomeningeal Metastases From Non-small-cell Lung Cancer

Objectives: We aim to determine the feasibility, safety, maximally tolerated dose (MTD), recommended dose and potential anti-tumor activity of intrathecal pemetrexed (IP).

Materials and Methods: Lung adenocarcinoma patients with recurrent or progressive leptomeningeal metastases (LM) after intrathecal chemotherapy were recruited. IP dose was escalated from 10 mg. A minimum of three patients and a maximum of six were enrolled in each cohort. Schedule protocol was IP twice per week for 2 weeks in induction therapy, followed by once per week for 4 weeks in consolidation therapy. Serial samples of plasma and cerebrospinal fluid (CSF) were obtained for pharmacokinetic studies.

Results: Thirteen patients were enrolled between March 2017 and July 2018. EGFR driver oncogene was identified in most of the patients. Severe adverse events (AEs) were encountered in 31% (4/13) of the cases, including myelosuppression, radiculitis, and elevation of hepatic aminotransferases (EHA). Study protocol was revised due to lethal myelosuppression. Following protocol revision, vitamin B12 and folic acid supplementation was given at the beginning of treatment, and myelosuppression was well-controlled. Dose-limiting toxicities (DLT) were myelosuppression, radiculitis, and EHA. Two patients (2/2) developed dose-limiting myelosuppression at 15 mg level. One patient (1/6) experienced dose-limiting radiculitis and EHA at 10 mg level. MTD was 10 mg. Response rate was 31% (4/13) and disease control rate was 54% (7/13). The drug concentration showed a decreasing trend in serial CSF samples following each IP. After IP, the peak plasma concentration was reached at 4 h in two cases, 6 h in two cases, 9 h in one case, and 12 h in one case, respectively.

Conclusion: Pemetrexed was appropriate for intrathecal administration. IP at 10 mg dose in combination with vitamin supplementation on the schedule of 1–2 times per week showed controllable toxicity and good efficacy. This regimen paves the way for subsequent clinical trial.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT03101579.

Simple and Rapid Quantification of the Multi-Enzyme Targeting Antifolate Pemetrexed in Human Plasma

BACKGROUND

Pemetrexed is an antifolate cytostatic drug that targets multiple enzymes involved in folate biosynthesis and is indicated for treatment of non-small-cell lung cancer and malignant pleural mesothelioma. As evidence for an exposure-response/toxicity relationship is accumulating, dose individualization using therapeutic drug monitoring may be a feasible strategy to optimize treatment. The purpose of this study was to develop a simple, sensitive, high-performance liquid chromatography method with UV detection for quantification of pemetrexed levels in human plasma.

METHOD

The method involves a simple protein precipitation, followed by ultra-performance liquid chromatography with ultraviolet detection at a wavelength of 254 nm. Pemetrexed was separated using a mobile phase with a linear gradient and a run time of only 7 minutes.

RESULTS

The assay has been validated over the concentration range 0.25-500 mg/L of pemetrexed. Accuracy for this assay ranged from -4.50% to 1.78%, and the within- and between-run coefficients of variation were <3.57%. Pemetrexed in plasma was proven to be stable for 8 months at -40°C.

CONCLUSIONS

The bioanalytical method we developed proved to be simple, accurate, precise, and fast. This analytical method is successfully in use for therapeutic drug monitoring and will be used for pharmacokinetic studies.

Basket Trials for Intractable Cancer

Currently, genomic characterization has become standard of care for tumor types such as non-small cell lung cancer, breast cancer, melanoma, and colorectal cancer. A deep understanding of genomic alterations in different tumor types would help identify potentially actionable genomic changes which occur across a wide variety of tumor types. A basket trial is a new type of clinical trial for which eligibility is based on the presence of a specific genomic alteration, irrespective of histology. Basket trials are phase II screening trials for the off-label use of a targeted drug in patients with the same genomic alterations for which it was approved. Intractable cancer refers to a type or condition of cancer which is unresponsive or resistant to treatment; intractable cancers may be classified into five subtypes as follows: hard-to-treat condition of common advanced cancer after multiple-line therapy, rare cancer in which no standard of care has been recommended, advanced cancer in which standard of care does not work well, cancer accompanied with organ dysfunction, and cancers in older or younger cancer patients. Previous studies have demonstrated that in basket trials, genomic-guided therapy yields clinical benefits in intractable cancer, thereby providing novel insights into the optimal clinical management of such cancers. In this review, we describe a novel way to classify intractable cancer, and summarize the current knowledge on such cancers. We additionally provide information on the role of basket trials in intractable cancer.

Population Pharmacokinetics of Pemetrexed in Adult Non-Small Cell Lung Cancer in Indian Patients

The objective of the study was to develop a population pharmacokinetic model of pemetrexed and identify factors contributing to variability in exposure in Indian patients. Plasma samples were obtained from a cohort of 85 patients following 500 mg/m² intravenous infusion and population pharmacokinetic analysis was performed using NONMEM (version 7.3.0). The stochastic approximation expectation maximization method was used to estimate parameters. The full covariate model approach was used by specifying clinically meaningful covariates a priori. Credible intervals obtained using Markov chain Monte Carlo Bayesian analysis were used to reduce the full covariate model by eliminating the covariates whose CI included the null. Model qualification was performed using visual predictive check and bootstrap. The final population parameter estimates and relative standard error for clearance (CL) was 3.3 L/h (10.8), central volume of distribution (V1) was 5.2 L (7.8), peripheral volume of distribution (V2) was 5.9 L (14.5) and intercompartmental clearance (Q) was 6.8 L/h (14.3). A large between-subject variability (50%-108% coefficient of variation) was observed in pharmacokinetic parameters. The percent coefficient of variation for the area under the plasma concentration-time curve from time zero to infinity was 72% and for maximum concentration was 68.25%. Diagnostic plots showed no major bias in the model. The final model included V1, V2, and Q scaled to body surface area raised to a fixed exponent of 1. Creatinine clearance and sex on clearance and albumin on V1 were statistically significant covariates based on Bayesian credible interval. However, traditional bootstrap resulted in a 95% confidence interval of the sex effect parameter including null. Given the size and nonsignificant sex effect in traditional bootstrap, it is considered clinically not significant.

The Evaluation of Animal Models in the Development of Anticancer Agents: From Preclinical to Clinical Tests

BACKGROUND

One of the main reasons for most of the anticancer drugs to fail in the late preclinical testing and early clinical trials is the differences in drug effects observed from animals and patients, and the challenge has been to find a balance to reduce the inherent differences from species.

OBJECTIVE

Predicting safe starting doses and dosing schedules for human clinical trials is the main purpose of toxicological studies of anticancer drugs.

METHODS

Relevant information and data were assimilated from manuscripts, congress publications, and online sources.

RESULTS

We systematically overview the cons and pros of animal models and briefed the ways to determine human clinical starting doses derived from animal toxicological studies for anticancer drugs.

CONCLUSION

This information helps smart select the suitable predictive model for anti-cancer drugs with the different mechanisms and emphasized the pharmaceutical challenges behind and ahead.

Safety of dose-reduced pemetrexed in patients with renal insufficiency

PURPOSE

Pemetrexed has been shown to be effective in the treatment of advanced and metastatic nonsquamous nonsmall cell lung cancer. In this population, renal insufficiency is common; however, pemetrexed is not recommended in patients with a creatinine clearance (CrCl) < 45 ml/min due to increased myelosuppression reported in phase I trials. The primary objective of this study is to determine the safety of dose-reduced pemetrexed in patients with a CrCl < 45 ml/min.

METHODS

This is a retrospective case series describing the incidence of grade 3 or higher toxicity in patients with CrCl < 45 ml/min treated with dose-reduced pemetrexed at The James Cancer Hospital and Solove Research Institute at The Ohio State University.

RESULTS

A total of eighteen patients were included. Seven (39%) patients experienced a grade ≥ 3 toxicity. Only 18% of administrations led to a grade ≥ 3 toxicity. Four (22%) patients had grade ≥ 3 hematologic toxicity; three of which were receiving concomitant platinum agents. The fourth patient had a CrCl < 30 ml/min. No patients receiving single-agent pemetrexed with a CrCl > 30 ml/min experienced grade ≥ 3 hematologic toxicity.

CONCLUSIONS

Dose-adjusted pemetrexed may be cautiously administered to patients with a CrCl between 30 and 45 ml/min. Extra caution is warranted in patients receiving concomitant chemotherapy with a platinum agent as well as those with a CrCl < 30 ml/min. Pemetrexed in combination with a platinum agent should not be routinely recommended for patients with a CrCl < 30 ml/min.

Evaluation of changes in renal function in PARAMOUNT: a phase III study of maintenance pemetrexed plus best supportive care versus placebo plus best supportive care after induction treatment with pemetrexed plus cisplatin for advanced nonsquamous non-small-cell lung cancer

OBJECTIVES

To assess the effect of long-term pemetrexed maintenance therapy on patients' renal function.

METHODS

In the PARAMOUNT phase III trial (NCT 00789373), pemetrexed was compared with placebo as maintenance treatment in advanced nonsquamous non-small-cell lung cancer patients who completed 4 cycles of pemetrexed plus cisplatin induction therapy. To evaluate changes in renal function during pemetrexed continuation maintenance treatment, we retrospectively analyzed changes in serum creatinine (sCr), treatment-emergent adverse events, dose delays and treatment discontinuations associated with impaired renal function.

RESULTS

Creatinine clearance ≥45 mL/min was required before the start of any cycle. Patients on pemetrexed maintenance had a significantly higher percentage maximum increase in sCr over baseline versus placebo for the range of ≥10% to ≥90% increase (p < .05). The risk of experiencing renal events leading to dose delays and discontinuations was higher with higher increases in sCr but reversible in most patients. sCr increases of ≥30% and ≥40% were associated with gender (female), age (<70 years) and longer exposure to pemetrexed compared with placebo. Sixteen (4%) pemetrexed patients and 1 (1%) placebo patient discontinued treatment due to drug-related renal events; 13/16 (81%) of those pemetrexed patients had sCr increases ≥30% and 7/13 (54%) had pre-existing conditions and/or were receiving nephrotoxic drugs.

CONCLUSIONS

The appearance of renal events leading to dose delays and/or treatment discontinuations was associated with sCr increase of at least 30%. However, it was difficult to identify patients at a higher risk of treatment discontinuation due to a drug-related renal event based only on changes in pre-maintenance laboratory values.

Renal damage induced by pemetrexed causing drug discontinuation: a case report and review of the literature

BACKGROUND

Pemetrexed maintenance therapy holds tremendous potential in improving the survival of patients with advanced pulmonary adenocarcinoma. Major side effects include myelosuppression and cutaneous reactions. However, little data are available on pemetrexed nephrotoxicity. Our case describes clinically relevant renal events leading to treatment discontinuation in routine practice.

CASE PRESENTATION

We report a case of a 69-year-old Moroccan man treated for metastatic non-small cell lung cancer. He was not on any other medications and he did not receive any nephrotoxic agents. He was exposed to intravenously administered contrast from thoracoabdominal computed tomography in the week of his last pemetrexed treatment. He developed kidney disease related to pemetrexed. He was submitted to renal biopsy, which showed acute tubular damage and interstitial fibrosis. His kidney function remained impaired, but stable, after discontinuation of pemetrexed therapy. He died 5 months later.

CONCLUSIONS

Medical oncologists should be aware of renal adverse events for patients with advanced non-small cell lung cancer eligible for pemetrexed maintenance therapy. Suggestions for mitigating the risk for renal toxicities (dehydration, non-steroidal anti-inflammatory drugs and zoledronic acid, radiocontrast agents) during pemetrexed maintenance should be followed to enable early detection and management of this adverse event.

Non-steroidal anti-inflammatory drugs induce severe hematologic toxicities in lung cancer patients receiving pemetrexed plus carboplatin: A retrospective cohort study

Purpose

As the major toxicity induced by pemetrexed plus carboplatin is severe hematologic toxicities, the aim of this study was to determine the risk factors for severe hematologic toxicities in lung cancer patients.

Methods

We retrospectively investigated data from lung cancer patients who had received pemetrexed plus carboplatin, with or without bevacizumab. This observational study was carried out at Ehime University Hospital using electronic medical records dating from July 2009 to March 2015. Severe hematologic toxicities were defined as grade 3 or 4, according to the Common Terminology Criteria for Adverse Events, version 4.0.

Results

Forty-two patients were included in the study. The incidence of grade 3 or 4 hematologic toxicities during the first cycle of chemotherapy and during all cycles was 19.0% and 16.1%, respectively. Multivariate time-depend generalized estimating equations logistic regression analysis revealed that regular use of non-steroidal anti-inflammatory drugs (NSAIDs) was significantly associated with an increased risk of severe hematologic toxicities during all cycles (adjusted odds ratio (OR): 8.32, 95% confidence interval (CI): 1.27–54.38; p = 0.03), whereas creatinine clearance of <45 mL/min was not significantly associated with an increased risk of severe hematologic toxicities during all cycles (adjusted OR: 0.91, 95% CI: 0.25–3.34; p = 0.88).

Conclusions

The results suggest that severe hematologic toxicities in patients receiving carboplatin-based pemetrexed may be significantly induced by the inhibition of renal tubular pemetrexed secretion through drug–drug interactions between NSAIDs and pemetrexed rather than through glomerular filtration of pemetrexed, even with moderate to sufficient renal function.

A phase I pharmacokinetic and safety study of cabazitaxel in adult cancer patients with normal and impaired renal function

PURPOSE

Limited data are available on cabazitaxel pharmacokinetics in patients with renal impairment. This open-label, multicenter study assessed cabazitaxel in patients with advanced solid tumors and normal or impaired renal function.

METHODS

Cohorts A (normal renal function: creatinine clearance [CrCL] >80 mL/min/1.73 m²), B (moderate renal impairment: CrCL 30 to <50 mL/min/1.73 m²) and C (severe impairment: CrCL <30 mL/min/1.73 m²) received cabazitaxel 25 mg/m² (A, B) or 20 mg/m² (C, could be escalated to 25 mg/m²), once every 3 weeks. Pharmacokinetic parameters and cabazitaxel unbound fraction (F _U) were assessed using linear regression and mixed models. Geometric mean (GM) and GM ratios (GMRs) were determined using mean CrCL intervals (moderate and severe renal impairment: 40 and 15 mL/min/1.73 m²) versus a control (90 mL/min/1.73 m²).

RESULTS

Overall, 25 patients received cabazitaxel (median cycles: 3 [range 1-20]; Cohort A: 5 [2-13]; Cohort B: 3 [1-15]; and Cohort C: 5 [1-20]), of which 24 were eligible for pharmacokinetic analysis (eight in each cohort). For moderate and severe renal impairment versus normal renal function, GMR estimates were: clearance normalized to body surface area (CL/BSA) 0.95 (90% CI 0.80-1.13) and 0.89 (0.61-1.32); area under the curve normalized to dose (AUC/dose) 1.06 (0.88-1.27) and 1.14 (0.76-1.71); and F _U 0.99 (0.94-1.04) and 0.97 (0.87-1.09), respectively. Estimated slopes of linear regression of log parameters versus log CrCL (renal impairment) were: CL/BSA 0.06 (-0.15 to 0.28); AUC/dose -0.07 (-0.30 to 0.16); and F _U 0.02 (-0.05 to 0.08). Cabazitaxel safety profile was consistent with previous reports.

CONCLUSIONS

Renal impairment had no clinically meaningful effect on cabazitaxel pharmacokinetics.

Pemetrexed-Induced Rash May Be Prevented by Supplementary Corticosteroids

Pemetrexed, a chemotherapeutic drug, is highly active in non-small cell lung cancer and malignant pleural mesothelioma. Unfortunately, rashes are more commonly associated with pemetrexed than other chemotherapies, and it is recommended that patients receive corticosteroids (8 mg/d of dexamethasone) for 3 d, including the day of pemetrexed administration (day 1). However, the efficacy of corticosteroids in this context has not been fully verified. In this retrospective study, we evaluated the medical records of 78 patients who received pemetrexed between April 2009 and March 2014, to confirm whether supplementary corticosteroids prevented rash development. The incidence of rash was lower in the 47 patients who received supplementary corticosteroids (after day 1) compared with the incidence among the 31 patients who did not receive supplementary corticosteroids (19.1% vs. 38.7%). The average cutoff dosage of supplementary corticosteroids on day 2 and day 3 was 1.5 mg/d of dexamethasone, as calculated using the receiver operating characteristic curve, and the odds ratio was 0.33 (95% confidence interval: 0.12-0.94). Administration of ≥1.5 mg of corticosteroids on day 2 and day 3 significantly reduced the severity of the rash compared to no supplementary treatment (grades 2/3, 13.3% vs. 33.3%, p<0.05). However, increasing the dose of corticosteroids had no additional effect on rash development. These results suggest that ≥1.5 mg of supplementary dexamethasone on day 2 and day 3 (in addition to day 1) may be necessary for preventing pemetrexed-induced rash, but high doses of dexamethasone (e.g., 8 mg/d) are unnecessary.

Identification and Quantitative Assessment of Uremic Solutes as Inhibitors of Renal Organic Anion Transporters, OAT1 and OAT3

One of the characteristics of chronic kidney disease (CKD) is the accumulation of uremic solutes in the plasma. Less is known about the effects of uremic solutes on transporters that may play critical roles in pharmacokinetics. We evaluated the effect of 72 uremic solutes on organic anion transporter 1 and 3 (OAT1 and OAT3) using a fluorescent probe substrate, 6-carboxyfluorescein. A total of 12 and 13 solutes were identified as inhibitors of OAT1 and OAT3, respectively. Several of them inhibited OAT1 or OAT3 at clinically relevant concentrations and reduced the transport of other OAT1/3 substrates in vitro. Review of clinical studies showed that the active secretion of most drugs that are known substrates of OAT1/3 deteriorated faster than the renal filtration in CKD. Collectively, these data suggest that through inhibition of OAT1 and OAT3, uremic solutes contribute to the decline in renal drug clearance in patients with CKD.

Lansoprazole Exacerbates Pemetrexed-Mediated Hematologic Toxicity by Competitive Inhibition of Renal Basolateral Human Organic Anion Transporter 3

Pemetrexed, a multitargeted antifolate, is eliminated by tubular secretion via human organic anion transporter 3 (hOAT3). Although proton pump inhibitors (PPIs) are frequently used in cancer patients, the drug interaction between PPIs and pemetrexed remains to be clarified. In this study, we examined the drug interaction between pemetrexed and PPIs in hOAT3-expressing cultured cells, and retrospectively analyzed the impact of PPIs on the development of hematologic toxicity in 108 patients who received pemetrexed and carboplatin treatment of nonsquamous non-small cell lung cancer for the first time between January 2011 and June 2015. We established that pemetrexed was transported via hOAT3 (Km = 68.3 ± 11.1 µM). Lansoprazole, rabeprazole, pantoprazole, esomeprazole, omeprazole, and vonoprazan inhibited hOAT3-mediated uptake of pemetrexed in a concentration-dependent manner. The inhibitory effect of lansoprazole was much greater than those of other PPIs and the apparent IC50 value of lansoprazole against pemetrexed transport via hOAT3 was 0.57 ± 0.17 µM. The inhibitory type of lansoprazole was competitive. In a retrospective study, multivariate analysis revealed that coadministration of lansoprazole, but not other PPIs, with pemetrexed and carboplatin was an independent risk factor significantly contributing to the development of hematologic toxicity (odds ratio: 10.004, P = 0.005). These findings demonstrated that coadministration of lansoprazole could exacerbate the hematologic toxicity associated with pemetrexed, at least in part, by competitive inhibition of hOAT3. Our results would aid clinicians to make decisions of coadministration drugs to avoid drug interaction-induced side effects for achievement of safe and appropriate chemotherapy with pemetrexed.

Effect of renal function on pemetrexed-induced haematotoxicity

PURPOSE

Pemetrexed (PEM) is an anticancer agent used for the treatment of non-small cell lung cancer, malignant pleural mesothelioma and thymoma. Reportedly, PEM has higher efficacy and safety when used in combination with platinum-based agents. However, there are only few reports on the safety of PEM in patients with an eGFR of ≤45 mL/min. We examined the effect of renal function on the safety of regimens containing PEM.

METHODS

We retrospectively reviewed 221 patients with lung cancer, malignant pleural mesothelioma or thymoma who received treatment with a PEM-containing regimen between 2009 and 2014. Subgroup analyses were performed on the basis of pre-treatment renal function: group A [creatinine clearance (CLcr), <45 mL/min]; group B (CLcr, 45-80 mL/min); and group C (CLcr, ≥80 mL/min). For the purpose of this analysis, the lowest documented blood cell counts and haemoglobin levels, the highest levels of serum creatinine, aspartate aminotransferase, alanine aminotransferase and CLcr from the time of initial administration up to prior to the start of second administration were considered.

RESULTS

Groups A, B and C had 8, 123 and 90 patients, respectively. The incidence of grade 2 thrombocytopaenia was significantly higher in group A as compared to that in groups B (P < 0.01) and C (P < 0.05). On multivariate analysis, only a CLcr of <45 mL/min was an independent risk factor for thrombocytopaenia of ≥grade 2.

CONCLUSION

When administering a PEM-containing regimen, thrombocytopaenia of ≥grade 2 is more likely to develop in patients with a CLcr of <45 mL/min.

Pemetrexed-Induced Nephrogenic Diabetes Insipidus

Pemetrexed is an approved antimetabolite agent, now widely used for treating locally advanced or metastatic nonsquamous non-small cell lung cancer. Although no electrolyte abnormalities are described in the prescribing information for this drug, several case reports have noted nephrogenic diabetes insipidus with associated acute kidney injury. We present a case of nephrogenic diabetes insipidus without severely reduced kidney function and propose a mechanism for the isolated finding. Severe hypernatremia can lead to encephalopathy and osmotic demyelination, and our report highlights the importance of careful monitoring of electrolytes and kidney function in patients with lung cancer receiving pemetrexed.

Potential role of pemetrexed in metastatic breast cancer patients pre-treated with anthracycline or taxane

Objectives

This article reviews pharmacology, pharmacokinetic properties, clinical efficacy, and safety in metastatic breast cancer patients, as well as the predictive biomarkers for outcome of treatment with pemetrexed-based regimens.

Methods

PubMed, Embase, OVID, and the Cochrane Library databases were searched from the beginning of each database without any limitations to the date of publication. Search terms were ‘‘pemetrexed’’ or ‘‘LY231514’’ or “Alimta”, “metastatic breast cancer”, and “advanced breast cancer”.

Results

There were 15 studies (n = 1002) meeting our criteria for evaluation. Eight single-agent trials (n = 551) and seven using combinations with other agents (n = 451) were identified that evaluated pemetrexed for use in patients with metastatic breast cancer. Response rates to pemetrexed as a single agent varied from 8% to 31%, and with combination therapy have been reported to be between 15.8% and 55.7%. With routine supplementation of patients with folic acid, dexamethasone, and vitamin B₁₂, the toxicity profile of these patients was mild, including dose-limiting neutropenia and thrombocytopenia, as well as lower grades of reversible hepatotoxicity and gastrointestinal toxicity. Expression of thymidylate synthase (TS) and other biomarkers are associated with the prognosis and sensitivity for pemetrexed in breast cancer.

Conclusion

Pemetrexed has shown remarkable activity with acceptable toxicities for treatment of metastatic breast cancer patients. Translational research on pemetrexed in breast cancer identified biomarkers as well as additional genes important to its clinical activity and toxicity. Further research is needed to clarify the role of pemetrexed in breast cancer treatment in order to guide oncologists.

New drug toxicities in the onco-nephrology world. Kidney Int. 2015;87:909-917. [PMID: 25671763 DOI: 10.1038/ki.2015.30]

New anticancer medications are rapidly entering the clinical arena offering patients with previously resistant cancers the promise of more effective therapies capable of extending their lives. However, adverse renal consequences develop in treated patients with underlying risk factors, requiring the nephrology community to be familiar with the nephrotoxic effects. The most common clinical nephrotoxic manifestations of these drugs include acute kidney injury, varying levels of proteinuria, hypertension, electrolyte disturbances, and at times chronic kidney disease. Thus, to practice competently in the 'onco-nephrology' arena, nephrologists will garner benefit from an update on older drugs with newly recognized nephrotoxic potential as well as newer agents, which may be associated with kidney injury. With that in mind, this brief update is meant to provide clinicians with the currently available evidence on the nephrotoxicity of a group of anticancer medications.

[Pemetrexed nephrotoxicity]

Pemetrexed belongs to a new generation of multitargeted antifolate cytotoxic agents. It is increasingly used as first-line treatment in combination with cisplatin, and as second-line treatment or maintenance monotherapy mainly in metastatic non-small cell lung cancer and in malignant mesothelioma. It is increasingly used as first-line treatment in combination with cisplatin in lung adenocarcinoma, and as second-line treatment or maintenance monotherapy in patients mainly controlled by the first-line to progression or poor tolerance. In mesothelioma, pemetrexed is indicated only in first-line with a platinum salt. The main side effect of pemetrexed is myelosuppression, which may be prevented by folinic acid supplementation. This review focuses on the progressive and cumulative emerging renal toxicity of pemetrexed, affecting five to ten percent of "long-term" pemetrexed-treated patients.

Identification of Tyr residues that enhance folate substrate binding and constrain oscillation of the proton-coupled folate transporter (PCFT-SLC46A1)

The proton-coupled folate transporter (PCFT) mediates intestinal folate absorption and transport of folates across the choroid plexus. This study focuses on the role of Tyr residues in PCFT function. The substituted Cys-accessibility method identified four Tyr residues (Y291, Y362, Y315, and Y414) that are accessible to the extracellular compartment; three of these (Y291, Y362, and Y315) are located within or near the folate binding pocket. When the Tyr residues were replaced with Cys or Ala, these mutants showed similar (up to 6-fold) increases in influx Vmax and Kt/Ki for [(3)H]methotrexate and [(3)H]pemetrexed. When the Tyr residues were replaced with Phe, these changes were moderated or absent. When Y315A PCFT was used as representative of the mutants and [(3)H]pemetrexed as the transport substrate, this substitution did not increase the efflux rate constant. Furthermore, neither influx nor efflux mediated by Y315A PCFT was transstimulated by the presence of substrate in the opposite compartment; however, substantial bidirectional transstimulation of transport was mediated by wild-type PCFT. This resulted in a threefold greater efflux rate constant for cells that express wild-type PCFT than for cells that express Y315 PCFT under exchange conditions. These data suggest that these Tyr residues, possibly through their rigid side chains, secure the carrier in a high-affinity state for its folate substrates. However, this may be achieved at the expense of constraining the carrier's mobility, thereby decreasing the rate at which the protein oscillates between its conformational states. The Vmax generated by these Tyr mutants may be so rapid that further augmentation during transstimulation may not be possible.

Emerging areas of research in the assessment of pharmacokinetics in patients with chronic kidney disease

Chronic kidney disease (CKD) has been shown to alter the pharmacokinetics of drugs that are eliminated not only via the renal pathway but also by nonrenal clearance and transport. Dosing recommendations in subjects with CKD have historically come from small pharmacokinetic (PK) studies, which have been insulated from the broader clinical development strategy. Opportunities for prospective strategic integration of both preclinical and clinical data on drug clearance mechanisms, model-based approaches, and clinical knowledge of therapeutic index are therefore often missed in designing and analyzing the results of PK studies in subjects with CKD, and eventually providing dosing recommendations. These considerations are valuable in designing informative PK studies in subjects with CKD, as well as for guiding kidney function-related inclusion/exclusion criteria in the broader clinical program and ultimately defining dosing guidelines that optimize benefit-risk balance for these special patient populations based on all available data. This paper offers points to consider for drug developers to increase adoption of a contemporary multidisciplinary approach, which includes key considerations on study design and conduct, methodologies for analysis (population PK and physiologically based PK modeling), and a roadmap to interpret the effect of kidney function on the overall benefit-risk profile of drugs in development.

[Impact of lung cancer treatments on renal function]

INTRODUCTION

Renal failure in patients with lung cancer may be multifactorial: related to the patients and their comorbidities, direct tumor compression or the toxicity of cancer treatments and other associated medications. This literature review is intended to describe the state of knowledge regarding the nephrotoxicity of treatments used in thoracic oncology.

FINDINGS

The majority of chemotherapy treatments are potentially nephrotoxic. Cisplatin and pemetrexed exhibit mainly renal tubular toxicity, while vascular renal impairment is found with gemcitabine and bevacizumab. Cisplatin results in acute renal failure in 30% of patients. Renal protective strategies (compliance with recommendations, limitation of nephrotoxic treatments, hydration, magnesium supplementation) must be employed systematically. Targeted therapies do not require any adjustment of the dosage in case of moderate or severe renal insufficiency but adapting the doses of biphosphonates to renal function is necessary.

CONCLUSION

This review highlights the need for monitoring of renal function in patients with lung cancer during treatment with chemotherapy or biphosphonates.

Effect of liver toxicity on clinical outcome of patients with non-small-cell lung cancer treated with pemetrexed

Liver toxicity (LT) is a common side effect of pemetrexed (PEM); however, the effect of LT on clinical outcome has not been investigated in patients with non-small-cell lung cancer (NSCLC) treated with PEM. Between June, 2009 and June, 2012, a total of 95 chemo-naive NSCLC patients received a PEM-containing regimen in our hospital. We reviewed the medical records of those 95 patients and evaluated the incidence of LT. Furthermore, we investigated the association between LT and clinical outcome. In this analysis, LT was defined as any grade of aspartate aminotransferase or alanine aminotransferase elevation. A total of 67 patients (70.5%) developed LT, which occurred mostly during the first treatment cycle. Among these, 10 patients (10.5%) required a delay in treatment or a dose reduction from the subsequent cycle and PEM discontinuation was required in 1 patient. The response rate (RR) was 43.3 and 21.4% in patients with and in those without LT, respectively (P=0.0387). The median progression-free survival (PFS) and overall survival (OS) were 6.3 and 24.2 months in patients with LT and 2.9 and 18.3 months in patients without LT, respectively (P<0.0001 for PFS and P=0.2426 for OS). The multivariate analysis demonstrated that LT exerted a significant positive effect on PFS (hazard ratio = 0.341; P<0.0001). In conclusion, LT was frequently observed in NSCLC patients treated with PEM; however, it was generally easily manageable. The improvement in RR and PFS observed in patients with LT suggested that LT may be a useful predictor of a favorable outcome in this patient population.

Weekly nab-paclitaxel in combination with carboplatin as first-line therapy in patients with advanced non-small-cell lung cancer: analysis of safety and efficacy in patients with renal impairment

INTRODUCTION

Renal impairment in cancer patients can affect treatment tolerability and outcomes. This analysis evaluated the safety and efficacy of nab-paclitaxel (nab-P) versus solvent-based paclitaxel (sb-P), both in combination with carboplatin (C), in patients with advanced non-small-cell lung cancer (NSCLC) and renal impairment.

METHODS

Untreated patients with stage IIIB/IV disease with NSCLC and a performance status of 0/1 were randomly assigned (1:1) to receive 100 mg/m(2)nab-P weekly plus C (under the curve = 6, every 3 weeks) or 200 mg/m(2) sb-P plus C (under the curve = 6) every 3 weeks. The primary end point was overall response rate.

RESULTS

Of 1038 treated patients in the phase III trial, 38% had mild renal impairment (creatinine clearance > 50 to ≤ 80 mL/min; n = 198 for nab-P/C and n = 206 for sb-P/C) and 5% had moderate renal impairment (creatinine clearance ≤ 50 mL/min: n = 26 for nab-P/C and n = 27 for sb-P/C). For nab-P/C versus sb-P/C, the treatment difference in efficacy in patients with either level of renal impairment was comparable to the overall population but did not reach statistical significance, with an overall response rate of 35% versus 27% (response rate ratio, 1.324; P = .060) in patients with mild renal impairment, and 31% versus 19% (response rate ratio, 1.662; P = .300) in patients with moderate renal impairment. Overall survival and progression-free survival were nonsignificantly longer for nab-P/C versus sb-P/C in these subsets. Patients with renal impairment experienced less grade 3 or higher neutropenia and sensory neuropathy, but more thrombocytopenia and anemia with nab-P/C versus sb-P/C.

CONCLUSION

nab-P/C proved beneficial and tolerable in patients with advanced NSCLC and mild and moderate renal impairment.

Evaluation of a novel rash scale and a serum proteomic predictor in a randomized phase II trial of sequential or concurrent cetuximab and pemetrexed in previously treated non-small cell lung cancer

Background

Candidate predictive biomarkers for epidermal growth factor receptor inhibitors (EGFRi), skin rash and serum proteomic assays, require further qualification to improve EGFRi therapy in non-small cell lung cancer (NSCLC). In a phase II trial that was closed to accrual because of changes in clinical practice we examined the relationships among candidate biomarkers, quantitative changes in tumor size, progression-free and overall survival.

Methods

55 patients with progressive NSCLC after platinum therapy were randomized to receive (Arm A) cetuximab, followed by pemetrexed at progression, or (Arm B) concurrent cetuximab and pemetrexed. All received cetuximab monotherapy for the first 14 days. Pre-treatment serum and weekly rash assessments by standard and EGFRi-induced rash (EIR) scales were collected.

Results

43 patients (20-Arm A, 23-Arm B) completed the 14-day run-in. Median survival was 9.1 months. Arm B had better median overall (Arm B = 10.3 [95% CI 7.5, 16.8]; Arm A = 3.5 [2.8, 11.7] months P = 0.046) and progression-free survival (Arm B = 2.3 [1.6, 3.1]; Arm A = 1.6 [0.9, 1.9] months P = 0.11). The EIR scale distributed ratings among 6 rather than 3 categories but ordinal scale rash severity did not predict outcomes. The serum proteomic classifier and absence of rash after 21 days of cetuximab did.

Conclusions

Absence of rash after 21 days of cetuximab therapy and the serum proteomic classifier, but not ordinal rash severity, were associated with NSCLC outcomes. Although in a small study, these observations were consistent with results from larger retrospective analyses.

Trial registration

Clinicaltrials.gov Identifier NCT00203931