The effects of food on the pharmacokinetic profile of oral vinorelbine

Fed or fasted state for oral therapies in breast cancer treatment? A comprehensive review of clinical practice recommendations

In the last decades several anti-cancer drugs have been developed to treat patients with breast cancer, many of them orally administered, with ongoing efforts to substitute parenteral drugs with oral therapy. The latter is attractive because of its convenience and ease of administration, finally improving quality of life. The drawback of oral administration is that exposure to the drug is affected by different factors and the high variability, combined with the relatively narrow therapeutic index of most of these agents, would predispose some individuals to risk for treatment inefficacy or increase toxicity. Among these factors, food plays a central role since it can influence the pharmacokinetic profile of several drugs. Consequently, health care providers and patients should be aware of possible interaction to optimize treatment. In this review a systematic evaluation of package inserts and literature have been performed to analyse the effect of fed or fasted state on pharmacokinetic of all oral drugs currently approved for breast cancer, offering clear recommendations for their use daily practice.

A randomised, multicentre open-label phase II study to evaluate the efficacy, tolerability and pharmacokinetics of oral vinorelbine plus cisplatin versus intravenous vinorelbine plus cisplatin in Chinese patients with chemotherapy-naive unresectable or metastatic non-small cell lung cancer

Background

A phase II study to evaluate the efficacy, tolerability and pharmacokinetics of oral or intravenous vinorelbine (VRL) plus cisplatin (CDDP) in Chinese patients with non-small cell lung cancer (NSCLC).

Methods

One hundred and thirty-one patients were randomised to oral VRL 60 mg/m² (arm A) or intravenous VRL 25 mg/m² (arm B) on days 1 and 8, plus CDDP 80 mg/m² on day 1 (both arms). VRL was increased to 80 mg/m² (arm A) or 30 mg/m² (arm B) in cycles 2-4 in the absence of toxicity. Primary efficacy endpoint was objective response rate (ORR). VRL pharmacokinetics was evaluated for possible drug-drug interactions with CDDP.

Results

ORR was 25.8% in arm A and 23.1% in arm B. Disease control rate was 72.7% in arm A, 72.3% in arm B. Median overall survival was 16.1 months in arm A and 19.0 months in arm B. Median progression-free survival was 4.6 months in arm A and 4.9 months in arm B. Forty-three point nine percent and 86.2% of patients had grade 3/4 neutropenia in arms A and B, respectively; incidence of febrile neutropenia was low (6.1% and 9.2%, respectively). Frequency of grade 3/4 non-haematological adverse events was also low. VRL pharmacokinetics was not affected by co-administration of CDDP.

Conclusions

Oral and intravenous VRL in combination with CDDP is effective and well-tolerated in Chinese patients with advanced NSCLC. VRL pharmacokinetics is unaffected by CDDP co-administration. Oral VRL could be an effective alternative to intravenous VRL as a first-line treatment for NSCLC, as it optimises treatment convenience while maintaining high efficacy.

Effect of ethnicity on vinorelbine pharmacokinetics: a population pharmacokinetics analysis

Background

Pharmacokinetics of vinorelbine is mainly known from studies conducted in European patients. Interethnic differences in drug disposition may, however, induce interethnic variation in drug exposure. This paper aimed to evaluate the effect of ethnicity on the bioavailability and clearance of oral and intravenous vinorelbine.

Methods

Oral and intravenous vinorelbine pharmacokinetics data in Asian patients were pooled from two-phase II studies of patients with non-small-cell lung cancer or advanced breast cancer in China. Blood vinorelbine and its active metabolite, 4′-O-deacetylvinorelbine, were quantified using liquid chromatography–tandem mass spectrometry. Bayesian pharmacokinetic parameters were calculated and vinorelbine monotherapy results (intravenous 25 mg/m²; oral 60 mg/m²) of the Asian data set were compared to a reference European data set (intravenous 30 mg/m²; oral 80 mg/m²). Subsequently, a population pharmacokinetics analysis was conducted in a combined cohort (Asian data set + historical vinorelbine pharmacokinetics database) to investigate for a potential effect of ethnicity.

Results

Pharmacokinetics data from the Asian data set (oral: n = 47; intravenous: n = 34) was compared to the European reference data set (oral: n = 48; intravenous: n = 48). Mean apparent clearance of oral vinorelbine and mean absolute clearance of intravenous vinorelbine was comparable between the Asian and reference European data set. A population pharmacokinetic analysis (oral: n = 222; intravenous: n = 111) demonstrated no influence of ethnicity on oral and intravenous vinorelbine bioavailability and clearance.

Conclusion

Vinorelbine pharmacokinetics were found to be comparable between Asian and European patients. No relevant influence of ethnicity on vinorelbine bioavailability and clearance for oral and intravenous routes of administration was observed.

Rapid LC-MS/MS method for quantification of vinorelbine and 4-O-deacetylvinorelbine in human whole blood suitable to monitoring oral metronomic anticancer therapy

A rapid and sensitive LC-MS/MS method for therapeutic drug monitoring oral vinorelbine (VRL) metronomic anticancer chemotherapy has been developed and validated. Analysis of VRL and its main active metabolite 4-O-deacetylvinorelbine (M1) was performed in whole blood matrix. Both analytes were extracted by protein precipitation and separated on an Onyx monolith C18 , 50 × 2 mm column then quantified by positive electrospray ionization and multiple reaction monitoring mode. The LLOQ was 0.05 ng/mL for both VRL and M1. Linearity was up to 25ng/mL with R2  ≥ 0.994. The intra- and inter-assay precisions were ≤ 11.6 and ≤ 10.4% while the ranges of accuracy were [-8.7%; 10.3%] and [-10.0; 7.4%] for VRL and M1, respectively. The clinical suitability of the method has been proved by the determination of the CTrough blood concentrations of VRL and M1 in 64 nonsmall cell lung cancer elderly patients. The analytical performance of the assay was suitable for pharmacokinetic monitoring of VRL and M1, allowing the personalization of the VRL metronomic treatments.

Cisplatin plus oral vinorelbine as first-line treatment for advanced non-small-cell lung cancer: a prospective study confirming that the day-8 hemogram is unnecessary

INTRODUCTION

Cisplatin plus oral vinorelbine, one of the standard treatments for metastatic non-small-cell lung cancer (NSCLC), is associated with a high rate of neutropenia, and a hemogram is performed on day 8. We analyzed the oncologists' opinions and the result of the hemogram on day 8 to address the question of whether this hemogram could be avoided.

MATERIALS AND METHODS

Fifty-eight chemotherapy-naive, advanced NSCLC patients were included. Each received intravenous doses of 75 mg/m(2) cisplatin on day 1 plus oral vinorelbine [60 mg/m(2) in the first cycle (80 mg/m(2) in subsequent cycles) on days 1 and 8], every 3 weeks, for a maximum of six cycles.

RESULTS

Out of 257 cycles analyzed, oral vinorelbine was administered on day 8 in 214 (83.2 %) and the dose was canceled in 6 cycles (2.3 %) due to hematological toxicity. On analyzing the patients to whom chemotherapy had been administered on day 8, based on medical opinion without the doctor knowing the hemogram result, we found that the cycle had been administered with a hemogram showing fewer than 1,500 × 10(6) neutrophils in only 3 of the 185 evaluable cycles [event rate of 1.6 %, with confidence interval 95 % = (0.34-4.67 %)].

CONCLUSION

The hemogram on day 8 can be avoided and oral vinorelbine administered in relative safety in patients with good performance status, when confirmed by the clinician's perception, thereby making this regimen more comfortable for the patient. This is the first prospective study to examine this issue.

A Novel Active Targeting Preparation, Vinorelbine Tartrate (VLBT) Encapsulated by Folate-Conjugated Bovine Serum Albumin (BSA) Nanoparticles: Preparation, Characterization and in Vitro Release Study

Vinorelbine tartrate (VLBT), as a kind of high hydrophilic and temperature-induced degradation drug, was prepared into nanoparticles by a desolvation procedure. Bovine serum albumin (BSA), as a drug carrier, was stabilized by chemical cross-linking with glutaraldehyde. Firstly, the optimization process of preparing VLBT-loaded BSA nanoparticles (VLBT-BSANPs) was accomplished using response surface methodology (RSM) by desolvation. Then VLBT-BSANPs were conjugated with folate, namely Fa-BSANPs-VLBT. Hence targeting drug carrier delivery system loading VLBT was produced. In this study, the characteristics of the nanoparticles, such as the amount of folate conjugation, surface morphology, surface chemistry, physical status of VLBT in Fa-BSANPs-VLBT, stability of Fa-BSANPs-VLBT with mannitol and in vitro drug release behavior were all investigated. The VLBT-BSANPs were obtained under optimum conditions, with a mean particle size (MPS) of 155.4 nm and a zeta potential (ZP) of −32.97 mV at a pH value of 5.4. Drug loading efficiency (DLE) and drug entrapment efficiency (DEE) of this obtained drug were approximately 45.6% and 90.6%, respectively.

Inoperable stage III non-small cell lung cancer: Current treatment and role of vinorelbine

Most lung cancer patients are diagnosed with a non-resectable disease; and around 40% in advanced stages. Stage III non-small cell lung cancer (NSCLC) is a heterogeneous disease with great variations in its clinical extent which presents a major therapeutic challenge. Although chemo-radiotherapy treatment has become the most widely used, there is currently no consensus on the best standard treatment and the experience of the therapy team plays an important role in the decision taking. We review the treatment of inoperable stage III NSCLC and the role of concomitant vinorelbine in this clinical scenario.

Pegylated liposomal doxorubicin (Caelyx®) and oral vinorelbine in first-line metastatic breast cancer patients previously treated with anthracyclines

Doxorubicin is highly effective and widely used in breast cancer; however, its use is limited by cardiotoxicity related to its cumulative dose. In previous studies, pegylated liposomal doxorubicin (PLD) has shown an acceptable toxicity profile with minimal cardiotoxicity. Between June 2006 and October 2009, 27 metastatic breast cancer patients were treated with first-line PLD and vinorelbine at the University of Florence, Radiotherapy Unit. PLD (30 mg/m²) was administered on day 1, and oral vinorelbine (60 mg/m²) was administered on days 1 and 8 of a 4-week cycle. All patients were previously treated with anthracycline-based adjuvant chemotherapy. Median age was 52 years (range 38-69) and median time to metastasis was 78.5 months. There were no treatment interruptions or discontinuation for cardiac toxicity and no treatment-related deaths. Grade 3 hematological toxicity was observed in 18.6% of patients, and 3.7% had grade 3 non-hematological adverse events. With a median follow-up of 13.2 months (range 3-33), median response duration was 6.1 months, and median PFS was 5.3 months. The overall clinical benefit rate was 55.5%. Our experience adds to evidence supporting the activity and cardiac safety of PLD and vinorelbine in metastatic breast cancer patients previously treated with anthracycline-based adjuvant chemotherapy.

Acceptance of oral chemotherapy in breast cancer patients - a survey study

Background

Oral (p.o.) chemotherapy treatments gained increasing importance in the palliative treatment of metastatic breast cancer (MBC). Aim of this survey was to evaluate the acceptance of p.o. treatment and patients' individual attitudes towards it.

Methods

A specific 14 item-questionnaire was designed. Patients suffering from breast cancer receiving a newly launched p.o. or i.v. chemotherapy treatment were prospectively evaluated during 4 months of time. 224 questionnaires using descriptive statistics, chi-square test, Spearman correlation were evaluated.

Results

Patients' median age was 54 years, 164 received i.v., 60 p.o therapy. 89% with p.o. and 67% with i.v. regimens would choose p.o. over i.v. therapy, if equal efficacy is guaranteed. Significant differences were especially found in terms of personal benefit (55% i.v., 92% p.o.), reduced feeling of being ill due to p.o. treatment (26% i.v., 65% p.o.), better coping with disease due to p.o. therapy (36% i.v., 68% p.o.). Side effects were significantly less often reported under p.o. treatment (19% p.o. vs. 53% i.v.)

Conclusion

P.o. chemotherapy shows a high acceptance in MBC patients under palliative therapy. Compliance can be achieved in particular through a differentiated indication, patient education and competent support along a p.o. treatment.

A dose escalation study of biweekly oral vinorelbine and gemcitabine in patients with solid tumors

PURPOSE

To determine the maximum tolerated doses (MTDs) and the dose-limiting toxicities of a biweekly administration of oral vinorelbine and gemcitabine in patients with advanced solid tumors.

PATIENTS AND METHODS

Twenty-eight patients with advanced stage solid tumors were enrolled, and 12 (42.9%) of them were chemotherapy naive. Escalating doses of vinorelbine (50-70 mg/m2 per os) and gemcitabine (800-1,000 mg/m2 as a 30-min intravenous infusion) were administered on days 1 and 15 in 4-week cycles.

RESULTS

MTDs were reached at 70 mg/m2 p.o. for vinorelbine and 900 mg/m2 for gemcitabine. Grade 4 neutropenia, febrile neutropenia, grade 4 nausea/vomiting and treatment delay due to grade 3 neutropenia were the dose-limiting events during the first cycle of chemotherapy. A total of 94 chemotherapy cycles were administered with only one episode of febrile neutropenia and no toxic deaths. Severe (grade 3-4) neutropenia occurred in 10% of cycles while non-hematological toxicity was mild with grade 2-3 asthenia occurring in 17 (18%) cycles. Objective responses were achieved in patients with prostate and non-small cell lung cancer.

CONCLUSIONS

The combination of biweekly oral vinorelbine (70 mg/m2) and gemcitabine (900 mg/m2) is a well-tolerated regimen with promising results in patients with advanced solid tumors.

Oral vinorelbine in the treatment of non-small cell lung cancer: rationale and implications for patient management

Vinorelbine is an established treatment for advanced non-small cell lung cancer (NSCLC), both as a single agent and in combination chemotherapy. Recently, an oral form of this agent has been developed. Before accepting an established agent in a different administration form, rigorous testing is required to answer such questions as reliable bioavailability, continued safety and preservation of efficacy. In addition, an oral agent must provide patient convenience and acceptance, while being an economically sound approach. Oral vinorelbine was found to have acceptable and reliable pharmacokinetic profiles at clinically relevant dosage levels. Oral vinorelbine was found to have approximately 40% bioavailability; thus, a dose of 80 mg/m(2) orally is the equivalent of 30 mg/m(2) intravenously, and 60 mg/m(2) orally is the equivalent of 25 mg/m(2) intravenously. Studies also concluded a lack of food effect on the administration of oral vinorelbine. In addition, no drug-drug interactions were found with a variety of commonly used antineoplastic agents.Vinorelbine, either orally or intravenously, has been investigated in randomised phase II trials as a single agent and in combination with cisplatin or carboplatin in patients with NSCLC. In general, response and survival results with oral vinorelbine appeared similar to the intravenous agent. Adverse-effect profiles were also similar for the two formulations. Clearly, the issue of venous irritation does not exist with oral vinorelbine; however, nausea and vomiting were more frequent when vinorelbine was administered orally compared with intravenously when no planned antiemetic therapy is given.

Oral versus intravenous administration of vinorelbine as a single agent for the first-line treatment of metastatic nonsmall cell lung carcinoma (NSCLC): A randomized phase II trial

OBJECTIVES

Many patients with metastatic nonsmall cell lung carcinoma (NSCLC) cannot tolerate intravenous chemotherapy. Orally active agents would be more convenient and thus could improve their quality of life.

METHODS

A total of 189 patients were randomized 2:1, 181 patients received treatment, 120 PO and 61 IV vinorelbine, 158 patients had stage IV and 31 stage IIIB disease. Among patients who received PO vinorelbine, the median age was 72 years, 62% were males; the Karnofski Performance Status (KPS) was 80-100 in 71%. These compare with a median age of 70 years, 56% male, and KPS of 80-100 in 65% of patients who received IV vinorelbine. Oral vinorelbine 60 mg/m2 was to be dose-escalated to 70 mg/m2 after the initial 3-weekly doses if there was no unacceptable toxicity. Intravenous vinorelbine was to be given 30 mg/m2 weekly.

RESULTS

Five patients (4%) on PO and 8 (13%) on IV vinorelbine had a confirmed partial response, 56 (44%) and 29 (46%) had stable disease, respectively. Median time-to-disease-progression was 16.6 weeks (PO) versus 23.9 weeks (IV), and the median survival was 26 weeks (PO) versus 40.9 weeks IV vinorelbine. Median survival on PO vinorelbine for patients with KPS 60-70 was 8.3 weeks versus 43 weeks (IV). On PO vinorelbine 59 patients (57%) were dose escalated, 9 (7.5%) were dose reduced, and 10 (8.3%) did not receive PO vinorelbine at week 4. Pharmacokinetic studies confirmed PO vinorelbine exposure was significantly less than IV exposure.

CONCLUSION

The inability to escalate the dose of PO vinorelbine above 60 mg/m2 weekly resulted in inferiority to IV vinorelbine at 30 mg/m2 weekly, especially in patients with poor performance status.

Evaluation of oral versus intravenous dose of vinorelbine to achieve equivalent blood exposures in patients with solid tumours

Patient's preference is for oral chemotherapy when both oral and i.v. are available, provided that efficacy is equivalent. Reliable switch from oral to i.v. is possible if correspondence between respective doses has been established. Vinorelbine oral was developed as a line extension of VRL i.v. on the basis that similar AUCs result in similar activities. From a first crossover study on 24 patients receiving VRL 25 mg/m2 i.v. and 80 mg/m2 oral data extrapolation concluded on AUCs bioequivalence between Vinorelbine 30 mg/m2 i.v. and 80 mg/m2 oral. A new trial was performed to support this calculation. In a crossover design study on patients (PS 0-1) with advanced solid tumours (44% breast carcinoma), VRL was administered (30 mg/m2 i.v., 80 mg/m2 oral) with a standard meal and 5-HT3 antagonists, at 2 weeks interval. Pharmacokinetics was performed over 168 h and VRL was measured by LC-MS/MS. Statistics included bioequivalence tests. Forty-eight patients were evaluable for PK: median age 58 years (25-71), PS0/PS1: 20/28, M/F: 11/37. Mean AUCs were 1,230 +/- 290 and 1,216 +/- 521 ng/ml for i.v. and oral, respectively. The confidence interval of the AUC ratio (0.83-1.03) was within the required regulatory range (0.8-1.25) and proved the bioequivalence between the two doses. The absolute bioavailability was 37.8 +/- 16.0%, and close to the value from the first study (40%). Patient tolerability was globally comparable between both forms with no significant difference on either haematological or non-haematological toxicities (grade 3-4). This new study, conducted on a larger population, confirmed the reliable dose correspondence previously established between vinorelbine 80 mg/m2 oral and 30 mg/m2 i.v.

Phase II trial of oral vinorelbine for the treatment of metastatic breast cancer in patients ≥65 years of age: an NCCTG study

BACKGROUND

A one-stage phase II trial was conducted to assess the tumor response rate and toxicity profile of single agent oral vinorelbine as first or second-line chemotherapy for women at least 65 years of age with metastatic breast cancer.

PATIENTS AND METHODS

Twenty-five patients with metastatic breast cancer aged > or = 65 years of age were enrolled to receive oral vinorelbine on a weekly basis. The oral vinorelbine was given at 60 mg/m2 weekly for the first four doses and was increased to 70 mg/m2 for the subsequent administrations if there was no grade 4 neutropenia or no more than one episode of grade 3 neutropenia. Therapy was continued until progression or intolerable toxicity.

RESULTS

Twenty-five patients were included and evaluable for analysis. One patient (4%) achieved a partial response (PR) that lasted for more than 13 months. Two additional patients remained stable for at least 6 months for a clinical benefit rate (PR + stable disease) of 12%. The 1-year survival rate was estimated to be 48% (95% CI 30% to 74.5%). Median time to progression was estimated to be 4.7 months (95% CI 2.0-5.5 months) and the 9-month disease progression-free rate was estimated to be 8% (95% CI 30.9% to 74.5%). The treatment was fairly well tolerated with grade 3 neutropenia in 12.5%, fatigue in 12.5% of the patients, and grade 2 neuromotor and neurosensory toxicities in 12.5% and 8.3%, respectively.

CONCLUSION

Oral vinorelbine as a single agent at these dose and schedule in this population of women > or = 65 years is well tolerated but has a low level of objective efficacy for the treatment of metastatic breast cancer.

Oral Vinorelbine and Cisplatin with Concomitant Radiotherapy in Stage III Non-Small Cell Lung Cancer (NSCLC): A Feasibility Study

BACKGROUND

Concurrent chemoradiotherapy has improved survival in inoperable stage III non-small cell lung cancer (NSCLC). This phase I trial was performed in order to establish a dose recommendation for oral vinorelbine in combination with cisplatin and simultaneous radiotherapy.

PATIENTS AND METHODS

Previously untreated patients with stage IIIB NSCLC received concurrent chemoradiotherapy with 66 Gy and 2 cycles of cisplatin and oral vinorelbine which was administered at 3 different levels (40, 50 and 60 mg/m2). This was to be followed by 2 cycles of cisplatin/ vinorelbine oral consolidation chemotherapy. The study goal was to determine the maximal recommended dose of oral vinorelbine during concurrent treatment.

RESULTS

11 stage IIIB patients were entered into the study. The median radiotherapy dose was 66 Gy. Grade 3-4 toxicity included neutropenia, esophagitis, gastritis and febrile neutropenia. The dose-limiting toxicity for concurrent chemoradiotherapy was esophagitis. 9 patients received consolidation chemotherapy, with neutropenia and anemia/thrombocytopenia grade 3 being the only toxicities. The overall response was 73%.

CONCLUSION

Oral vinorelbine 50 mg/m2 (days 1, 8, 15 over 4 weeks) in combination with cisplatin 20 mg/m2 (days 1-4) is the recommended dose in combination with radiotherapy (66 Gy) and will be used for concurrent chemoradiotherapy in a forthcoming phase III trial testing the efficacy of consolidation chemotherapy in patients not progressing after chemoradiotherapy.

[Oral vinorelbine: pharmacology and treatment outcome in non-small cell bronchial carcinoma and breast carcinoma]

The development of an oral formulation of vinorelbine (Navelbine softgelatine capsules, Pierre Fabre Pharma, Freiburg i.Br., Germany) represents a significant advance in the treatment of patients with cancer. Oral chemotherapy is more convenient for the patients and brings significant time savings. Vinorelbine is rapidly absorbed after oral ingestion. The bioavailability is in the range of 33 to 43% and is not affected by concomitant food intake or by vomiting occuring 1.5 h or later after dosing. No significant differences in the pharmacokinetics of oral vinorelbine were observed between elderly (> or =70 years) and younger patients. The recommended dose schedule for oral vinorelbine is 60 mg/m(2) weekly for the initial 3 weeks (cycle 1) and 80 mg/m(2) weekly thereafter. However, if severe neutropenia is encountered during the first cycle, treatment is continued with weekly doses of 60 mg/m(2). Bioavailability studies have demonstrated that oral vinorelbine doses of 60 and 80 mg/m(2) are comparable to intravenous doses of 25 and 30 mg/m(2), respectively. Several clinical studies have demonstrated that the new oral formulation of vinorelbine can be safely administered, even to elderly patients, and is comparable in activity to intravenous vinorelbine in advanced non-small cell lung cancer (NSCLC) and metastatic breast cancer (MBC). A randomized phase II comparison of oral vinorelbine at the recommended dose schedule vs. intravenous vinorelbine at 30 mg/(2) in patients with advanced NSCLC found no significant differences in response rate, progression-free and overall survival between the two treatments. In studies of combination chemotherapy using vinorelbine plus cisplatin or carboplatin in advanced NSCLC, or vinorelbine plus taxanes, capecitabine,epirubicin, or the monoclonal HER2/neu antibody trastuzumab in MBC, intravenous vinorelbine could be completely or partially replaced by oral vinorelbine, resulting in maintained efficacy, good tolerability and improved patient convenience. Concurrent chemoradiation with oral vinorelbine and cisplatin was shown to be well tolerated and produced significant down-staging in patients with locally advanced NSCLC. Metronomic chemotherapy is a new treatment approach designed to maximize the antiangiogenic effect. Oral vinorelbine given every other day at low doses is currently evaluated in patients with refractory solid tumors. Oral vinorelbine has also proven useful as a substitute for intravenous vinorelbine in patients experiencing intractable acute tumor pain during or after intravenous infusion of vinorelbine.

Oral versus intravenous vinorelbine: clinical safety profile

The availability of chemotherapeutic drugs administrable by oral route represents a step forward in the management of cancer patients. Among oral agents, vinorelbine is particularly interesting for its pharmacological characteristics and clinical efficacy. Oral vinorelbine is rapidly absorbed (1.5-3 hours) with an elimination half-life of approximately 40 hours. It shows a low level of binding to plasma proteins (13%), is highly bound to platelets (78%) and has a hepatic metabolism and an absolute bioavailability of 40% with a moderate and similar interpatient variability for the two forms. Food has no influence on the pharmacokinetic profile of oral vinorelbine even if nausea/vomiting is less frequent and less severe in the fed patients than in the fasting patients. Therefore, to ensure patient comfort, it is recommended that oral vinorelbine is administered with a snack. All the metabolites of oral vinorelbine have been identified and, among these, only deacetyl-vinorelbine presented activity demonstrating that for both oral and intravenous (i.v.) routes of administration the drug has the same metabolism pattern. Oral vinorelbine is eliminated mainly in a unconjugated form via the bile. In this process, the CYP 3A4 isoform of cytochrome P450 is mostly involved. Absorption of oral vinorelbine is not delayed in elderly patients. After oral administration, blood concentrations of vinorelbine in elderly patients are within the range of values observed in younger patients. The absolute bioavailability is close to 38% in elderly whereas it is close to 40% in younger patients. This difference is not significant. As compared to the intravenous drug, oral vinorelbine demonstrated linear pharmacokinetics as well an absolute bioavailability of approximately 40%, and a reliable dose-correspondence of 80 mg/m2 oral form --> 30 mg/m2 i.v. and 60 mg/m2 oral --> 25 mg/m2 i.v. Therefore, i.v. and oral forms show similar interindividual variability, same metabolism pattern, reproducible intra-patient blood exposure, and same pharmacokinetic-pharmacodynamic relationship. Oral vinorelbine has shown significant activity in advanced non-small cell lung cancer. Given at 60 mg/m2/week for the first 3 administrations and then increased to 80 mg/m2/week achieved the same efficacy as i.v. vinorelbine in terms of progression-free survival, overall survival, objective response. Mild-to-moderate gastrointestinal toxicity, easily manageable with standard treatment was recorded. Reproducible efficacy compared to previously reported results with vinorelbine i.v. Also, in advanced breast cancer, oral vinorelbine has shown significant activity with a good therapeutic index. Albeit no formal comparison between the oral and the intravenous formulations of vinorelbine has been made, however, the oral route seems to offer major advantages to patients who are faced with a clear decrease in the frequency of hospital admissions as compared to that needed to give intravenous chemotherapy.

Oral vinorelbine given as monotherapy to advanced, elderly NSCLC patients: a multicentre phase II trial

Vinorelbine intravenously (i.v.) demonstrated its efficacy and tolerability in advanced non-small cell lung cancer (NSCLC) patients, including elderly subjects. Since vinorelbine is now available as an oral formulation this phase II open study was designed to evaluate its activity and tolerability in advanced, elderly NSCLC patients. A total of 56 chemonaive patients were recruited from April 2001 through to March 2002. The dosage schedule, already tested in younger NSCLC patients, was 60 mg/m(2)once a week for three weeks (first cycle), followed by 80 mg/m(2) once a week until disease progression or development of unacceptable toxicity. A limited sampling scheme was used for performing pharmacokinetic analysis on 52 of 56 patients enrolled in the study. Treatment was well tolerated with grade 3/4 neutropenia in 11/17 patients (20/30%) and febrile neutropenia in 1 (2%). Six partial responses (11%) and 25 stable disease responses were recorded, with a disease control rate of 55%. Median overall survival was 8.2 months (95% Confidence Interval (CI) [6.2-11.3]). The clinical benefit response rate was 31% on 32 evaluable patients. Pharmacokinetic profiles appeared quite similar to the historical profiles recorded following i.v. administration. Oral vinorelbine appears to be a reasonable alternative to i.v. vinorelbine, both in terms of activity and tolerability, in advanced, elderly NSCLC patients.

Non–Small-Cell Lung Cancer in Elderly Patients: Influence of Age on Vinorelbine Oral Pharmacokinetics

The majority of cancer-related deaths are attributed to lung carcinoma. Age increases this incidence, which is also likely associated with physiologic modifications that affect drug pharmacokinetics and metabolism. Therefore, knowledge of pharmacokinetics in elderly patients is one of the major factors in deciding whether or not to reduce the dose to prevent toxicity. This phase II study was aimed at evaluating the influence of age on oral vinorelbine pharmacokinetics in elderly patients with non-small-cell lung cancer (NSCLC). Inclusion criteria were > 70 years of age; histologically or cytologically proven NSCLC; inoperable stage IIIB, IV, or delayed relapse of any stage becoming unresectable; Karnofsky performance status > 80%; and normal hematology and biochemistry. Blood-limited sampling at intervals of 1.5, 3, and 24 hours after dosing was performed during the first administration of oral vinorelbine at 60 mg/m2. Bayesian pharmacokinetic parameters were calculated through previously published nonlinear mixed-effect modeling (NONMEM), and compared with a reference population of 52 patients (age, 56 years 12) selected from vinorelbine pharmacokinetic database. There were 48 patients evaluable for pharmacokinetics out of the 52 elderly patients enrolled (age, 74 years 3). There was no difference between pharmacokinetic parameters, including the bioavailability factor evaluated by NONMEM, even without intravenous administration, and a similar interindividual variability (32%-33%) was observed between the 2 groups. Furthermore, no correlation between age (range, 31-82 years) and oral vinorelbine total clearance was observed in 100 patients pooled together. Therefore, no requirement for oral vinorelbine dose reduction was suggested from a pharmacokinetic standpoint.