A phase I/II study of pemetrexed and vinorelbine in patients with non-small cell lung cancer

Pemetrexed plus vinorelbine versus vinorelbine monotherapy in patients with metastatic breast cancer (KCSG-BR15-17): A randomized, open-label, multicenter, phase II trial

INTRODUCTION

Metastatic breast cancer refractory to anthracycline and taxanes often shows rapid progression. The development of effective and tolerable combination regimens for these patients is needed. This phase II trial investigated the efficacy of pemetrexed plus vinorelbine in patients with metastatic breast cancer.

METHODS

This randomized, open-label, phase II trial was conducted in 17 centers in Korea. Patients with advanced breast cancer who had previously been treated with anthracyclines and taxanes were randomly assigned in a 1:1 ratio to receive either vinorelbine or pemetrexed plus vinorelbine. Randomization was stratified by prior capecitabine treatment and hormone receptor status. The primary endpoint was investigator-assessed progression-free survival (PFS). Secondary endpoints included the objective response rate, overall survival, safety, and quality of life.

RESULTS

Between March 2017 and August 2019, a total of 125 patients were enrolled. After a median follow-up duration of 14.1 months, 118 progression events and 88 death events had occurred. Sixty-two patients were assigned to the pemetrexed plus vinorelbine arm, and 63 were assigned to the vinorelbine arm. Pemetrexed plus vinorelbine significantly prolonged PFS compared to vinorelbine (5.7 vs. 1.5 months, p < 0.001). The combination arm had higher disease control rate (76.8% vs. 45.9%, p = 0.001) and a tendency toward longer overall survival (16.8 vs. 10.5 months, p = 0.102). Anemia was more frequent in the pemetrexed plus vinorelbine arm per cycle compared with vinorelbine (7.9% vs. 1.9%, p < 0.001), but there was no difference in the incidence of grade 3-4 neutropenia per cycle between the pemetrexed plus vinorelbine arm and the vinorelbine single arm (14.7% vs. 19.5%, p = 0.066).

CONCLUSIONS

This phase II study showed that pemetrexed plus vinorelbine led to a longer PFS than vinorelbine. Adverse events of pemetrexed plus vinorelbine were generally manageable.

Impact of pharmacogenetics on variability in exposure to oral vinorelbine among pediatric patients: a model-based population pharmacokinetic analysis

PURPOSE

Better understanding of pharmacokinetics of oral vinorelbine (VNR) in children would help predicting drug exposure and, beyond, clinical outcome. Here, we have characterized the population pharmacokinetics of oral VNR and studied the factors likely to explain the variability observed in VNR exposure among young patients.

DESIGN/METHODS

We collected blood samples from 36 patients (mean age 11.6 years) of the OVIMA multicentric phase II study in children with recurrent/progressive low-grade glioma. Patients received 60 mg/m² of oral VNR on days 1, 8, and 15 during the first 28-day treatment cycle and 80 mg/m², unless contraindicated, from cycle 2-12. Population pharmacokinetic analysis was performed using nonlinear mixed-effects modeling within the Monolix^® software. Fifty SNPs of pharmacokinetic-related genes were genotyped. The influence of demographic, biological, and pharmacogenetic covariates on pharmacokinetic parameters was investigated using a stepwise multivariate procedure.

RESULTS

A three-compartment model, with a delayed double zero-order absorption and a first-order elimination, best described VNR pharmacokinetics in children. Typical population estimates for the apparent central volume of distribution (V_c/F) and elimination rate constant were 803 L and 0.60 h^-1, respectively. Following covariate analysis, BSA, leukocytes count, and drug transport ABCB1-rs2032582 SNP showed a dramatic impact on V_c/F. Conversely, age and sex had no significant effect on VNR pharmacokinetics.

CONCLUSION

Beyond canonical BSA and leukocytes, ABCB1-rs2032582 polymorphism showed a meaningful impact on VNR systemic exposure. Simulations showed that the identified covariates could have an impact on both efficacy and toxicity outcomes. Thus, a personalized dosing strategy, using those covariates, could help to optimize the efficacy/toxicity balance of VNR in children.

Pemetrexed for advanced stage nonsquamous non-small cell lung cancer: latest evidence about its extended use and outcomes

Non-small cell lung cancer (NSCLC) is still the leading cause of cancer-related death, and the treatment of advanced NSCLC relies on systemic treatments. During the last decade, pemetrexed, an antifolate agent, gradually became a key component of the treatment for patients with advanced nonsquamous NSCLC. It has indeed been shown to be efficient for first-line, maintenance and second- or third-line treatment in this subgroup of NSCLC. Moreover, it is usually well tolerated, with few grade 3 and 4 toxicities. Several studies have tried to identify predictive biomarkers of pemetrexed efficacy. Due to pemetrexed's mechanism of action, thymidilate synthase expression predictive value was investigated but could not be demonstrated. Currently, more than 400 trials of pemetrexed for the treatment of nonsquamous NSCLC are ongoing.

Deriving therapies for children with primary CNS tumors using pharmacokinetic modeling and simulation of cerebral microdialysis data

The treatment of children with primary central nervous system (CNS) tumors continues to be a challenge despite recent advances in technology and diagnostics. In this overview, we describe our approach for identifying and evaluating active anticancer drugs through a process that enables rational translation from the lab to the clinic. The preclinical approach we discuss uses tumor subgroup-specific models of pediatric CNS tumors, cerebral microdialysis sampling of tumor extracellular fluid (tECF), and pharmacokinetic modeling and simulation to overcome challenges that currently hinder researchers in this field. This approach involves performing extensive systemic (plasma) and target site (CNS tumor) pharmacokinetic studies. Pharmacokinetic modeling and simulation of the data derived from these studies are then used to inform future decisions regarding drug administration, including dosage and schedule. Here, we also present how our approach was used to examine two FDA approved drugs, simvastatin and pemetrexed, as candidates for new therapies for pediatric CNS tumors. We determined that due to unfavorable pharmacokinetic characteristics and insufficient concentrations in tumor tissue in a mouse model of ependymoma, simvastatin would not be efficacious in further preclinical trials. In contrast to simvastatin, pemetrexed was advanced to preclinical efficacy studies after our studies determined that plasma exposures were similar to those in humans treated at similar tolerable dosages and adequate unbound concentrations were found in tumor tissue of medulloblastoma-bearing mice. Generally speaking, the high clinical failure rates for CNS drug candidates can be partially explained by the fact that therapies are often moved into clinical trials without extensive and rational preclinical studies to optimize the transition. Our approach addresses this limitation by using pharmacokinetic and pharmacodynamic modeling of data generated from appropriate in vivo models to support the rational testing and usage of innovative therapies in children with CNS tumors.

The place of pemetrexed in the management of non-small-cell lung cancer patients

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer death worldwide. Chemotherapy is included in the management of the majority of NSCLC patients either in addition to a local treatment (surgery/radiotherapy) or alone. In this setting, pemetrexed has become one of the most important partners of current chemotherapy regimens for nonsquamous NSCLC patients. Indeed, pemetrexed demonstrated a comparable efficacy to other previously available drugs in NSCLC, with however a better safety profile and an easier schedule of administration. In addition, pemetrexed demonstrated a greater efficacy in nonsquamous NSCLC that lead to an exploration of the underlying potential biological background. It is now suggested that the tumor thymidylate synthase level may act as a predictor of pemetrexed efficacy, therefore potentially providing clinicians in the future with a predictor of efficacy, which it is usually lacking with standard chemotherapies.

Pemetrexed in advanced non-small-cell lung cancer

IMPORTANCE OF THE FIELD

Current therapeutic options for advanced non-small-cell lung cancer (NSCLC) yield relatively modest improvements in survival leading to an ongoing search for new active treatment agents. In the past decade, pemetrexed has had an increasingly established role in the treatment of advanced NSCLC in both first- and second-line settings.

AREAS COVERED IN THIS REVIEW

Currently available published data on mechanism of action, pharmacokinetics, safety and efficacy of pemetrexed in the treatment of advanced NSCLC are described. Peer-reviewed publications on the development of pemetrexed and its clinical use in NSCLC were reviewed (1995 - 2009).

WHAT THE READER WILL GAIN

Pemetrexed is a multitargeted antifolate cytotoxic agent. Key Phase II and Phase III trials are described that have shown pemetrexed's efficacy in both the first- and second-line treatment of advanced NSCLC. The efficacy of pemetrexed seems to vary between squamous and nonsquamous histologies. Possible reasons for this are explored. Additionally, the potential role of pemetrexed in maintenance therapy is discussed.

TAKE HOME MESSAGE

Pemetrexed is an effective treatment for advanced NSCLC, with an overall favorable toxicity profile. There is growing evidence that, in patients treated with pemetrexed, nonsquamous tumors have improved outcomes compared to squamous cell tumors. Pemetrexed may also have a role in maintenance therapy for NSCLC.

Pemetrexed as first-line therapy for non-squamous non-small cell lung cancer

Pemetrexed is a new cytotoxic agent that is a standard of care for the second-line treatment of non-small cell lung cancer (NSCLC) and in combination with cisplatin in treatment of malignat pleural mesothelioma. It has been studied in numerous phase II and III trials in combination with different drugs or as single agent. Recently, pemetrexed has been approved in combination with cisplatin for the first-line treatment of patients with locally advanced or metastatic NSCLC other than squamous cell histology. The toxicity is acceptable and similar to that of other NSCLC regimens. The postinduction maintenance therapy with pemetrexed is being evaluated in a phase III, double-blind, placebo-controlled study.

Pemetrexed in the treatment of advanced non-squamous lung cancer

Pemetrexed, a new cytotoxic agent, is a potent inhibitor of thymidylate synthase and other folate-dependent enzymes. Firstly, pemetrexed was approved in combination with cisplatin for the treatment of malignant pleural mesothelioma. Successively, it has been studied, as single-agent, in phase II and III trials for second-line therapy of non-small cell lung cancer (NSCLC). Based on these results, pemetrexed has been registered for the treatment of recurrent NSCLC. The next step was to test pemetrexed plus cisplatin versus gemcitabine plus cisplatin, as first-line therapy in advanced NSCLC patients, in a phase III, non-inferiority, randomized trial. This trial reported the pemetrexed plus cisplatin regimen to be not inferior, in terms of activity and efficacy, to the control arm but statistically better tolerated. The role of pemetrexed as maintenance therapy after first-line therapy for advanced NSCLC is currently being evaluated into a phase III trial. The consistency of the results of these recent studies has identified a predictive effect of NSCLC non-squamous histology for pemetrexed. To date, pemetrexed is registered, at the dose of 500 mg/m(2) on day 1 of a 3-week schedule, in combination with cisplatin, for first-line therapy and, as single-agent, for second-line treatment of patients with non-squamous NSCLC.This review shows the latest and indicates the future developments of pemetrexed in the treatment of advanced NSCLC patients.

Tailoring treatment of nonsmall cell lung cancer by tissue type: role of pemetrexed

Pemetrexed (ALIMTA, LY231514, MTA) is a novel multitargeted antifolate that is currently approved for the treatment of metastatic nonsmall cell lung cancer (NSCLC). Recent evidence reveals that the drug's efficacy is limited to nonsquamous lung cancer histology. As we further understand the drug's mechanisms of action, new genomic and proteomic evidence is shedding light on why some patients respond while others do not. The first goal of this review is to briefly review pemetrexed's mechanism of action, resistance patterns, toxicity profile, and pharmacokinetics. We will also review the clinical trials that led to its use in NSCLC, with special attention to data showing that pemetrexed has greater efficacy in nonsquamous histologies of NSCLC. Furthermore, we will discuss the hypotheses for the genomic and proteomic basis for this variation in efficacy. Finally, we will report the future directions for pemetrexed as a personalized agent for nonsquamous NSCLC.

Pemetrexed in first-line treatment of non-small cell lung cancer

Pemetrexed is an antitumor agent traditionally used as monotherapy for the second-line treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) as well as in combination with cisplatin for the treatment of chemonaïve patients with unresectable malignant pleural mesothelioma. Recently, pemetrexed has been approved in combination with cisplatin for the first-line treatment of patients with locally advanced or metastatic NSCLC other than predominantly squamous cell histology. Studies that support the development of this indication are detailed in this review. We performed a PubMed/Medline database search to identify relevant literature from 1998 until August 2008. Bibliographies from identified references were searched, as well as were abstracts from the most relevant congresses in lung cancer area (American Society of Clinical Oncology Congress, World Conferences of Lung Cancer). We detailed pemetrexed studies in the first-line setting of NSCLC treatment, in monotherapy, in combination with platinum and also, with other agents. Data regarding efficacy differences related to different histologic types were also analyzed.

Review of the pemetrexed and gemcitabine combination in patients with advanced-stage non-small cell lung cancer

Pemetrexed is a new multitargeted antifolate that can be easily administered as a 10-min infusion every 3 weeks. The use of folic acid, vitamin B(12), and corticoid prophylaxis has significantly reduced pemetrexed-induced toxicity. Single-agent pemetrexed has shown antitumor activity in a wide range of solid tumors, including non-small cell lung cancer (NSCLC). Association with vinorelbine, cisplatin, carboplatin, and oxaliplatin have been tried, but the pemetrexed and gemcitabine combination, an easy to administer cisplatin-free doublet, has been documented in many phase 2 trials in the first-line treatment of advanced NSCLC. In vitro cytotoxic assays and phase I studies have defined several schedules of administration for pemetrexed and gemcitabine. The recommended dose is pemetrexed 500 mg/m(2) on day 1 or 8, and gemcitabine 1250 mg/m(2) on day 1 and 8, but it is unknown if pemetrexed should precede or follow gemcitabine and at what time interval. Published studies have failed to show significant differences in overall survival times despites response rates oscillating between 15% and 41%. The main toxicities are neutropenia, fatigue, skin rashes and elevated transaminases and seem to occur with similar rates in the many phase 2 trials. Hopes for the future are in tailored chemotherapy, since molecular markers of sensitivity are available for gemcitabine and pemetrexed, allowing to determinate in the future which patients will be most likely to benefit from the gemcitabine-pemetrexed doublet.

Pemetrexed pharmacokinetics and pharmacodynamics in a phase I/II study of doublet chemotherapy with vinorelbine: implications for further optimisation of pemetrexed schedules

The purpose of this study was to investigate the utility of plasma pharmacokinetic and pharmacodynamic measures including plasma deoxynucleosides, homocysteine and methylmalonic acid concentrations in understanding the time course and extent of the inhibition of thymidylate synthase (TS) by pemetrexed in the context of a phase I/II combination study with vinorelbine. Eighteen patients received supplementation with folic acid and Vitamin B₁₂ 1 week before beginning treatment with pemetrexed and vinorelbine administered in a dose-escalating manner on a 21-day cycle. Heparinised blood samples were collected from consenting patients in the first cycle for pharmacokinetic analyses and in the first two cycles for determination of plasma thymidine, deoxyuridine, homocysteine and methylmalonic acid concentrations. These values were correlated with response and toxicity. Plasma deoxyuridine was used as a measure of TS inhibition, and concentrations of deoxyuridine were significantly elevated relative to baseline on days 1 (P<0.01), 2 (P<0.001) and 3 (P<0.05) after treatment at all pemetrexed dose levels (400–700 mg m⁻²). The magnitude of deoxyuridine elevation correlated with pemetrexed area under the plasma concentration–time curve (AUC) (r²=0.23, P<0.05). However, deoxyuridine concentrations returned to baseline between 8 and 15 days after treatment with pemetrexed, suggesting that inhibition of TS was not durable. Pemetrexed AUC correlated with the percentage decline (relative to baseline) in both platelets (r²=0.58, P<0.001) and leucocytes (r²=0.26, P<0.05) at day 8. Baseline homocysteine was also significantly correlated with these measures of haematological toxicity (r²=0.37, P<0.01 and r²=0.39, P<0.01, respectively). In addition, there was a significant reduction of plasma homocysteine on days 8 (P<0.005) and 15 (P<0.05) in cycle 1 compared to baseline values. The results suggest that the TS inhibitory effects of pemetrexed are short-lived and make the case for a more frequent schedule of administration such as every 2 weeks. The lack of protracted TS inhibition may be due to concomitant vitamin administration, and this may be the mechanism by which vitamins prevent life-threatening toxicity from pemetrexed. Baseline homocysteine concentration remains a predictive marker for haematological toxicity even following folate supplementation.

Clinical activity of pemetrexed: a multitargeted antifolate anticancer agent

Pemetrexed is a new generation antifolate anticancer agent that inhibits several folate-dependent enzymes required for production of DNA and RNA intermediates. Early studies showed significant hematologic and nonhematologic toxicities with this agent. However it was found that many of these toxicities related to functional folate status and could be markedly reduced through routine supplementation with folic acid and vitamin B(12), without adversely affecting efficacy. Phase III studies with pemetrexed have established a clinical role for this drug as a single agent in the second-line treatment of non-small cell lung cancer and in combination with cisplatin for the frontline treatment of unresectable malignant pleural mesothelioma. Clinical trials of pemetrexed alone or in combination with other chemotherapeutic agents have shown considerable activity in many tumor types including colorectal, pancreatic and breast cancer, and urothelial tumors.

Role of pemetrexed in non-small cell lung cancer

Pemetrexed was approved for the treatment of relapsed or chemotherapy refractory non-small cell lung cancer patients, as it produced similar response and survival outcomes and less toxicity as compared to taxotere. Pemetrexed in combination with platinum analogs or with gemcitabine or vinorelbine, produce equivalent responses and overall survival results compared to combinations of platinum analogs with other drugs. The role of bevacizumab and the inhibitors of epithelial growth factor receptor also should be evaluated in selected patients with NSCLC treated with pemetrexed combinations. Further increases in drug dose may be possible using transfer of drug resistance genes in hematopoietic stem cells.

Emerging therapeutic options for Philadelphia-positive acute lymphocytic leukemia

Acute lymphocytic leukemia (ALL) is a heterogeneous group of disorders that are associated with a cure rate of > 80% in children. The prognosis in adults is considerably inferior, with age, disease bulk, leukemia karyotype and immune phenotype being prognostically relevant. Adult ALL treatment programs include induction, intensified consolidation and maintenance phases with CNS prophylaxis. The addition of imatinib in patients with BCR-ABL-positive ALL has improved the prognosis of this subgroup, but their survival is still poor. Initial data on the second-generation BCR-ABL inhibitors, dasatinib and nilotinib, indicate a potentially greater efficacy than imatinib, but the improvement is likely to be modest. The overall efforts in terms of developmental therapeutics in ALL are very modest and not in keeping with the urgent need for improvement. Most agents being investigated have mechanisms of action similar to those of existing agents for ALL therapy and thus represent modest opportunities to improve results. Of such agents, data on BCR-ABL inhibitors, sphingosomal vincristine, pemetrexed, talotrexin, annamycin and ABT-751 are reviewed.

A Phase I Study of Pemetrexed, Carboplatin, and Concurrent Radiotherapy in Patients with Locally Advanced or Metastatic Non–Small Cell Lung or Esophageal Cancer

PURPOSE

The primary objective of this phase I study was to determine the maximum tolerated dose for pemetrexed, alone and in combination with carboplatin, with concurrent radiotherapy.

EXPERIMENTAL DESIGN

Patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) or esophageal cancer were treated every 21 days for two cycles. Regimen 1 was pemetrexed (200-600 mg/m(2)); regimen 2 was pemetrexed (500 mg/m(2)) with escalating carboplatin doses (AUC = 4-6). Both regimens included concurrent radiation (40-66 Gy; palliative-intent doses were lower).

RESULTS

Thirty patients (18 locally advanced and 12 metastatic with dominant local symptoms) were enrolled, with an Eastern Cooperative Oncology Group performance status of 0/1/2 (n = 8/21/1). All dose levels were tolerable for regimen 1 (n = 18: 15 NSCLC and 3 esophageal cancers) and regimen 2 (n = 12: all NSCLC). In regimen 1, one dose-limiting toxicity (grade 4 esophagitis/anorexia) occurred (500 mg/m(2)). Grade 3 neutropenia (3 of 18 patients) was the main hematologic toxicity. In regimen 2, one dose-limiting toxicity (grade 3 esophagitis) occurred (500 mg/m(2); AUC = 6); grade 3/4 leukopenia (4 of 12 patients) was the main hematologic toxicity. Four complete responses (2 pathology proven) and eight partial responses were observed. When systemically active chemotherapy doses were reached, further dose escalation was discontinued, and a phase II dose-range was established (pemetrexed 500 mg/m(2) and carboplatin AUC = 5-6).

CONCLUSIONS

The combination of pemetrexed (500 mg/m(2)) and carboplatin (AUC = 5 or 6) with concurrent radiation is well tolerated, allows for the administration of systemically active chemotherapy doses, and shows signs of activity. To further determine efficacy, safety profile, and optimal dosing, the Cancer and Leukemia Group B study 30407 is currently evaluating this regimen in patients with unresectable stage III NSCLC.

An evaluation of pemetrexed in second-line treatment of non-small cell lung cancer

Pemetrexed is a novel antifolate antimetabolite that targets multiple folate-dependent enzymatic pathways and inhibits multiple enzymes involved in purine and pyrimidine synthesis. Its targets include pathways that, when amplified, are associated with reduced efficacy in conventional cytotoxic agents. As second-line treatment for advanced non-small cell lung cancer, (NSCLC) pemetrexed, when administered with folic acid and vitamin B12, has demonstrated comparable efficacy and a superior toxicity profile relative to docetaxel. A retrospective analysis of the Phase III trial of pemetrexed versus docetaxel shows a statistically significant longer toxicity-free survival time for pemetrexed compared with docetaxel. Newer targeted therapies, especially the epidermal growth factor receptor inhibitors gefitinib and erlotinib, have produced conflicting results and have only been compared with best supportive care and placebo. They should be compared directly to pemetrexed as second-line therapy in large, randomised studies of patients with advanced NSCLC. For patients with advanced recurrent NSCLC and good performance status who progress after first-line chemotherapy, pemetrexed should be considered as a new standard of care.