Phase I trial, including pharmacokinetic and pharmacodynamic correlations, of combination paclitaxel and carboplatin in patients with metastatic non-small-cell lung cancer

Polymeric Nanoparticles Simultaneously Delivering Paclitaxel Prodrug and Combretastatin A4 with Exceptionally High Drug Loading for Cancer Combination Therapy

Nanomedicines capable of delivering multiple drugs have become essential in combination therapy. However, the challenges of low drug loading capacity (DLC) and difficulties in administering dosages between different drugs significantly limit the antitumor efficacy. In this study, a nanomedicine constructed through a rational prodrug and nanocarrier design was reported for cancer combination therapy. Initially, a phenylborate ester (PBE) group-modified paclitaxel (PTX) prodrug (PTX-PBE) was synthesized and could self-assemble in water. Subsequently, combretastatin A4 (CA4) polymer conjugates, mPEG-PCA4 (PCA4), were synthesized as nanocarriers to facilitate the exceptionally high drug loading of PTX-PBE in a precisely controlled manner. Both the in vitro and in vivo experiments demonstrated that the PCA4 loading PTX-PBE nanoparticles (PCA4/PTX-PBE NPs) exhibited potent antitumor efficacy and favorable biocompatibility. Our approach provides a straightforward, efficient, and controllable strategy for the co-delivery of pharmaceuticals in clinical cancer combination therapy.

Paclitaxel improves thrombopoiesis in the absence of thrombopoietin receptor (Mpl)

BACKGROUND

Platelets are critical for thrombosis and hemostasis. The THPO-MPL pathway is the primary pathway for generating thrombocytes. Dysregulation of thrombopoiesis results in platelet formation and/or function-related disorders, such as thrombocytopenia. Paclitaxel is an extensively utilized chemotherapeutic agent and its activity may be related to platelets, but the effect of paclitaxel on thrombocytopoiesis warrants comprehensive exploration.

OBJECTIVES

We focused on identifying factors that regulate thrombocyte production and elucidating paclitaxel's regulatory mechanisms on thrombocytopoiesis, with a particular emphasis on discovering mechanisms that bypass THPO-MPL pathways.

METHODS

We performed drug screenings using the Tg(mpl:eGFP) zebrafish model in vivo to identify Food and Drug Administration-approved compounds capable of boosting thrombocyte production. An injury experiment was used to evaluate thrombocyte function. Bromodeoxyuridine assays, terminal deoxynucleotidyl transferase dUTP nick-end labeling, and RNA sequencing analyses were performed to explore cytological and molecular mechanisms. Routine blood testing and flow cytometry were used to analyze mouse phenotypes.

RESULTS

We found that paclitaxel expands thrombocytes by accelerating the proliferation of thrombocytic lineage cells in zebrafish and elevates platelet levels in mice. This effect occurs by bypassing the thrombopoietin receptor (Mpl). We found that paclitaxel promotes thrombopoiesis, potentially involving the JAK2-ERK1/2 MAPK signaling cascade, a pathway integral to MPL and other regulators. Our results further demonstrate that ERK1/2 is at least partially downstream of JAK2 in paclitaxel-induced thrombopoiesis.

CONCLUSION

Paclitaxel could promote thrombopoiesis by bypassing Mpl but presumably via the JAK2-ERK1/2 MAPK pathways. It will aid in understanding the relationship between paclitaxel and platelets clinically, and paclitaxel may have potential value for safeguarding platelets and improving thrombocytosis in related diseases.

Durvalumab plus carboplatin-etoposide treatment in a patient with small-cell lung cancer on hemodialysis: a case report and literature review

Little is known about the efficacy and safety of durvalumab plus carboplatin-etoposide treatment in patients with extensive-disease (ED) small-cell lung cancer (SCLC) on hemodialysis. Here, we present a case of a 67-year-old man with pleuroperitoneal communication on continuous ambulatory peritoneal dialysis who was diagnosed with ED-SCLC based on a cytological analysis of the peritoneal fluid. He was switched from peritoneal dialysis to hemodialysis and received durvalumab (1500 mg/body on day 1) plus carboplatin (area under the concentration-time curve = 5, 125 mg on day 1) and etoposide (50 mg/m2 on days 1 and 3) as first-line therapy. During the first cycle, grade 2 anemia, grade 3 neutropenia, and grade 3 upper gastrointestinal bleeding occurred; therefore, durvalumab and reduced doses of carboplatin and etoposide were administered. No other severe adverse events occurred, and a partial response was observed after four cycles. Our findings indicate that durvalumab plus carboplatin-etoposide treatment is safe and effective even in patients on hemodialysis.

Paclitaxel exposure-toxicity analysis reveals a pharmacokinetic determinant for dose-limiting neutropenia in East-Asian solid tumor patients: results from two prospective, phase II studies

PURPOSE

The time of a paclitaxel (PTX) concentration remains above 0.05 μM (Tc > 0.05) has been associated with PTX-induced adverse effects in Caucasians, while limited studies were reported in Asians. This study was aimed to explore the characteristics of Tc > 0.05 and the relationship between PTX exposure and toxicity in East-Asian patients.

METHODS

This study was based on two prospective phase II clinical trials and patients with advanced nasopharyngeal cancer (NPC) and non-small cell lung cancer (NSCLC) who were naïve to PTX were included independently. Eligible patients receive PTX (175 mg/m²) and carboplatin (AUC = 5) treatment every 3 weeks. PTX pharmacokinetic analysis was accessed. The relationship between PTX exposure and toxicities after first cycle as well as clinical efficacy was evaluated.

RESULTS

A total of 93 NPC and 40 NSCLC patients were enrolled. PTX exposure was consistent in two trials with average Tc > 0.05 duration of 38.8 h and 38.4 h, respectively. Average Tc > 0.05 in patients with grade 3/4 neutropenia was significantly higher than those without severe neutropenia in NPC patients (P = 0.003) and NSCLC patients (P = 0.007). Cut-off value of Tc > 0.05 were identified from the NPC cohort and then verified in the NSCLC cohort, dividing patients into high exposure Tc > 0.05 group (> 39 h) and low exposure group (≤ 39 h). Incidence of grade 3/4 neutropenia were significantly higher in the high exposure group in NPC cohort (43.3% vs 10.0%, P < 0.001) and NSCLC cohort (42.1% vs 9.5%, P = 0.028). No significant relationship between Tc > 0.05 and efficacy were observed.

CONCLUSION

Patients with PTX Tc > 0.05 duration above 39 h experience more severe neutropenia than those under 39 h. Prospective studies are needed to verify this threshold.

A phase Ib/II and pharmacokinetic study of EP0057 (formerly CRLX101) in combination with weekly paclitaxel in patients with recurrent or persistent epithelial ovarian, fallopian tube, or primary peritoneal cancer

BACKGROUND

EP0057 (formerly CRLX101) is an investigational nanoparticle-drug conjugate (NDC) of a cyclodextrin-based polymer backbone plus camptothecin, a topoisomerase-1 inhibitor. Prior studies showed efficacy in recurrent or persistent, epithelial ovarian, fallopian tube or primary peritoneal cancer (EOC).

METHODS

This phase Ib/2 trial assessed safety and efficacy of EP0057 Q2W plus weekly paclitaxel in patients with EOC. The recommended phase 2 dose (RP2D) was identified using a 3+3 design. The single-arm phase 2 assessed overall response (ORR) per RECIST 1.1 in patients previously treated with bevacizumab. Secondary objectives included progression free survival (PFS) and duration of response.

RESULTS

The RP2D was established as 15 mg/m² EP0057 Q2W plus 80 mg/m² paclitaxel administered 3 weeks on/1 week off. Nine patients enrolled on phase 1b, with no DLTs; 21 additional patients enrolled on phase 2. All completed >1 cycle. Median age was 62 (44-76) years, 57% ≥3 prior therapies. For the primary analysis, 6/19 patients with prior bevacizumab had confirmed responses (ORR=31.6% (95% CI: 15.4% to 54.0%)) including one complete response (CR). Median PFS was 5.4 months. Most common grade 3/4 adverse events attributed to treatment were decreased neutrophil count (13, 43%) and anemia (3, 10%).

CONCLUSIONS

Although the observed ORR was not statistically better than the historical control rate, EP0057 remains an interesting option for treatment of recurrent EOC. EP0057 exhibits high plasma drug retention, slow clearance, and controlled slow release of CPT from the polymer when administered alone and with paclitaxel. (NCT02389985) 242 words.

Comparision of Radiochemotherapy Applications that Committing with Two Different Chemotherapies Route in Locally Advanced Lung Cancer

Objective

This study investigated pre- and post-treatment tumor and lymph node dimension response rates and differences between side-effect profiles in patients with locally advanced inoperable nonsmall-cell lung cancer (NSCLC) receiving radiotherapy (RT) and concurrent chemotherapy (CT).

Materials and Methods

A total of 30 inoperable patients who had not previously received RT and having a mean age of 58.73±8.65 years with sufficient hematological reserves and normal hepatic and renal functions were included in the study. Those with pleural effusion, supraventricular lymph node metastasis, and N3 lymph node involvement were excluded. Group I (n=15) received a 21-day 75 mg/m² cisplatin (D1) and 15 mg/m² vinorelbine (D1, D8), whereas Group II (n=15) received 45 mg/m2 paclitaxel and AUC2 carboplatin weekly. RT was administered using a linear accelerator device with the 3D conformal RT technique at 6-18 MV energy with a 1.8-2 Gy fraction for 6-7 weeks.

Results

Patients were randomized into Group I receiving RT and concurrent cisplatin-vinorelbine and Group II receiving weekly paclitaxel-carboplatin CT. Pre- and post-treatment tumor and lymph node dimensions significantly differed in both groups (p<0.001 and p<0.01, respectively). No significant change was observed in post-RT tumor and lymph node dimensions in terms of applied CT regimens (p>0.05).

Conclusion

The significant response achieved with concurrent RT and CT in groups I and II in the local advanced stage of NSCLC is important for local tumor control. Responses to treatment in the group of two arms did not differ.

Inability of Current Dosing to Achieve Carboplatin Therapeutic Targets in People with Advanced Non-Small Cell Lung Cancer: Impact of Systemic Inflammation on Carboplatin Exposure and Clinical Outcomes

BACKGROUND

The presence of elevated systemic inflammation in people with advanced non-small cell lung cancer (NSCLC) is associated with significantly shorter survival following carboplatin-based chemotherapy.

OBJECTIVE

This study investigated whether novel factors, such as systemic inflammation [platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR)], impact carboplatin pharmacokinetics and drug utilisation. The study also examined the ability of current and alternate dosing regimens to meet therapeutic targets.

METHODS

Seventy-two people with advanced NSCLC treated with carboplatin-based (460-1050 mg) doublet chemotherapy were recruited and pharmacokinetic data (n = 61) were analysed using non-linear mixed modelling. Covariate analysis was performed to investigate the impact of standard and novel patient characteristics of carboplatin pharmacokinetics. A Monte Carlo simulation of 100,000 representative NSCLC patients evaluated the ability of the Calvert formula and novel dosing strategies to achieve the targeted therapeutic range. The associations between systemic inflammation and chemotherapy drug utilisation (cycles received, relative dose intensity (RDI) and second-line uptake) and clinical endpoints were also investigated in the pharmacokinetic cohort, and two independent cohorts of people with advanced NSCLC from the Chemotherapy Dosing in Cancer-Related Inflammation (CDCRI) database that were administered carboplatin-paclitaxel (n = 37) or carboplatin-gemcitabine (n = 358).

RESULTS

In all cohorts, 25-53% of people had elevated systemic inflammation (NLR > 5 or PLR > 300). In the pharmacokinetic cohort, no patients achieved the desired therapeutic target of carboplatin. Carboplatin exposure was related to renal function, as estimated using the Cockcroft-Gault formula, albumin and inflammation (NLR). In the pharmacokinetic cohort, increasing carboplatin area under the curve (AUC) correlated with greater reductions in red blood cells and haemoglobin. In this cohort, the average measured AUC of partial responders was 2.4 mg·min/mL. Also in the pharmacokinetic cohort, only 12% of people with an NLR > 5 received four or more cycles of chemotherapy, compared with 62% of patients with an NLR ≤ 5 (p < 0.001). For people in the CDCRI cohort receiving carboplatin-gemcitabine, those with an NLR > 5 also received less cycles (four or more cycles, 41% vs. 60%; p < 0.01) as well as less second-line chemotherapy (46% vs. 60%; p = 0.02) compared with patients without inflammation. People in the pharmacokinetic cohort with an NLR > 5 had 12 months less median survival compared with people with an NLR ≤ 5 (6.5 vs. 18 months; p = 0.08). Similarly, overall survival was significantly shortened in people in the CDCRI cohort receiving carboplatin-gemcitabine with an NLR > 5 compared with those with an NLR ≤ 5 (7 vs. 12 months; p < 0.001), and Cox regression analysis showed a 1.5-fold (1.3-2.1; p < 0.001) increased hazard of death associated with the increased systemic inflammation. Simulations of the newly developed model-based and Calvert dosing assessed the ability to reach this study's proposed actual target AUC of 2.2-2.6 mg·min/mL. These showed current Calvert dosing was predicted to result in substantial overexposure in patients with high systemic inflammation. The newly developed model showed equivalent levels of carboplatin therapeutic target achievement across the spectrum of inflammation observed in the lung cancer population.

CONCLUSION

An alternate model-based dosing strategy for carboplatin was developed and is predicted to result in consistent drug exposure across the population and improve attainment of therapeutic targets. Further studies of this new model are warranted in people with advanced NSCLC.

Does Older Age Lead to Higher Risk for Neutropenia in Patients Treated with Paclitaxel?

PURPOSE

There is ongoing concern regarding increased toxicity from paclitaxel in elderly patients, particularly of severe neutropenia. Yet, data so far is controversial and this concern is not supported by a clinically relevant age-dependent difference in pharmacokinetics (PK) of paclitaxel. This study assessed whether age is associated with increased risk for paclitaxel-induced neutropenia.

METHODS

Paclitaxel plasma concentration-time data, pooled from multiple different studies, was combined with available respective neutrophil count data during the first treatment cycle. Paclitaxel pharmacokinetic-pharmacodynamic (PK-PD) data was modeled using a non-linear mixed effects approach and a semiphysiological neutropenia model, where systemic paclitaxel exposure was linked to reduced proliferation of neutrophils. The impact of age was evaluated on relevant variables in the model, using a significance threshold of p < 0.005.

RESULTS

Paclitaxel PK-PD data was evaluated from 300 patients, with a median age of 65 years (range 23-84 years), containing 116 patients ≥70 years (39%). First cycle neutrophil counts were adequately described by a threshold effect model of paclitaxel on the proliferation rate of neutrophils. Age as a continuous or dichotomous variable (≥70 versus <70 years) did not significantly impact sensitivity of the bone marrow to paclitaxel nor the average maturation time of neutrophils (both p > 0.005), causing a decline in the respective interindividual variability of <1%.

CONCLUSION

Results from this large retrospective patient cohort do not suggest elderly patients to be at an increased risk of developing paclitaxel-associated neutropenia during the first treatment cycle. Reflexive dose reductions of paclitaxel in elderly patients are unlikely to improve the risk of severe neutropenia and may be deleterious.

Phase 1 study of veliparib (ABT-888), a poly (ADP-ribose) polymerase inhibitor, with carboplatin and paclitaxel in advanced solid malignancies

PURPOSE

Veliparib is an oral inhibitor of poly (ADP-ribose) polymerase (PARP)-1 and -2. PARP-1 expression may be increased in cancer, and this increase confers resistance to cytotoxic agents. We aimed to determine the recommended phase 2 dose (RP2D), maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and pharmacokinetics (PK) of veliparib combined with paclitaxel and carboplatin.

METHODS

Eligibility criteria included patients with advanced solid tumors treated with ≤ 3 prior regimens. Paclitaxel and carboplatin were administered on day 3 of a 21-day cycle. Veliparib was given PO BID days 1-7, except for cycle 1 in the first 46 patients to serve as control for toxicity and PK. A standard "3 + 3" design started veliparib at 10 mg BID, paclitaxel at 150 mg/m², and carboplatin AUC 6. The pharmacokinetic (PK) disposition of veliparib, paclitaxel, and carboplatin was determined by LC-MS/MS and AAS during cycles 1 and 2.

RESULTS

Seventy-three patients were enrolled. Toxicities were as expected with carboplatin/paclitaxel chemotherapy, including neutropenia, thrombocytopenia, and peripheral neuropathy. DLTs were seen in two of seven evaluable patients at the maximum administered dose (MAD): veliparib 120 mg BID, paclitaxel 200 mg/m², and carboplatin AUC 6 (febrile neutropenia, hyponatremia). The MTD and RP2D were determined to be veliparib 100 mg BID, paclitaxel 200 mg/m², and carboplatin AUC 6. Median number of cycles of the three-agent combination was 4 (1-16). We observed 22 partial and 5 complete responses. Veliparib did not affect paclitaxel or carboplatin PK disposition.

CONCLUSION

Veliparib, paclitaxel, and carboplatin were well tolerated and demonstrated promising antitumor activity.

Impact of Older Age on the Exposure of Paclitaxel: a Population Pharmacokinetic Study

PURPOSE

Limited available data suggest that older patients are more prone to develop paclitaxel-induced toxicity than their younger peers. It remains unclear whether this is related to age-dependent pharmacokinetics (PK) of paclitaxel. Primary objective of this study was to determine the influence of older age on the PK of paclitaxel.

METHODS

PK data of patients aged ≥70 years who received paclitaxel intravenously at the Netherlands Cancer Institute (NKI) and the Radboud University Medical Center between September 2012 and May 2017 were collected. These prospectively collected data were pooled with previously published databases from multiple clinical trials conducted at the NKI and Erasmus MC Cancer Institute. A previously developed 3-compartment population PK model with saturable distribution and elimination was used to describe paclitaxel plasma concentration-time data. Hereafter, influence of age on paclitaxel PK was assessed in a previously established full covariate model.

RESULTS

In total, paclitaxel PK data from 684 patients were available, consisting of 166 patients ≥70 years (24%). Median age of the cohort was 61 years (range 18 to 84 years). The impact of age, either treated as a continuous or dichotomous covariate (<70 versus ≥70 years), on the elimination of paclitaxel was only marginal but statistically significant (both p < 0.001 with no clinically relevant decrease in interindividual variability). For a typical patient, maximal elimination capacity decreased by only 5% for a 10-year increment of age.

CONCLUSION

In this extensive multi-center dataset, which included a considerable number of older patients, older age had no clinically relevant impact on paclitaxel PK.

Impact of Isotope Dilution Mass Spectrometry (IDMS) Standardization on Carboplatin Dose and Adverse Events

BACKGROUND

When using area under the concentration-time curve-based strategies for dosing carboplatin, accurate estimation of glomerular filtration rate is required for determining dose. Commonly, the Cockcroft-Gault equation is used, which is dependent on measurement of serum creatinine (SCr). Because analysis of SCr changed to an isotope dilution mass spectrometry (IDMS) standard, we sought to determine the impact of this assay change on carboplatin dosing and related toxicity.

METHODS

This was a single-center, retrospective chart review of adults treated with carboplatin between April 2008 and April 2010 divided into cohorts that initiated carboplatin before or after IDMS standardization. End points included grade 3 thrombocytopenia, decrease in platelet count, and hospitalization and were evaluated in cohorts based on concomitant chemotherapy.

RESULTS

The chart review identified 158 patients, with 63 patients in the pre-IDMS group and 95 patients in the post-IDMS group. Average SCr (pre 1.01 mg/dl vs post 0.86 mg/dl, p<0.001) and average carboplatin dose (pre 580 mg vs post 703 mg, p<0.001) were significantly different between the groups. The frequency of grade 3 thrombocytopenia was not statistically significant across three partner chemotherapy cohorts before and after IDMS implementation.

CONCLUSION

IDMS standardization led to an overall decrease in SCr with subsequent increase in carboplatin doses. However, no increase in recorded adverse events was observed, suggesting that the clinical relevance in toxicity from higher doses was minimal.

Dose-banding of carboplatin: rationale and proposed banding scheme

Background. In dose-banding (DB) prescribed doses of cancer chemotherapy are fitted to doseranges or ‘bands’ and standard doses for each band are provided using a selection of pre-filled infusions or syringes, either singly or in combination. DB is used for several drugs where dose is based on body surface area. No DB-scheme has been reported for carboplatin, which, in clinical practice, is routinely dosed according to renal function.

Study objective. To assess the rationale for DB of carboplatin with regards to factors that influence dosing accuracy, develop a DB scheme, and discuss its potential use and limitations.

Methods. Prospective evaluations of carboplatin area under the plasma concentration – time curve (AUC) following application of the Calvert-formula were identified by a literature search. A relevant carboplatin dose range for construction of a DB-scheme with Calvert-formula based doses was obtained from published glomerular filtration rate distributions for patients receiving carboplatin.

Results. A DB-scheme was developed for individually calculated carboplatin doses of 358–1232 mg, with 35 mg increments between each standard dose and a maximum deviation of 4.7% from prescribed dose. The proposed DB-scheme covers the GFR-ranges 47–221 mL/min and 26–151 mL/min for patients receiving doses based on the target AUCs of 5 and 7 mg/mL/min, respectively.

Conclusion. There is a strong scientific rationale to support DB of carboplatin. The proposed banding scheme could introduce benefits to patients and healthcare staff but, as with other DB schemes, should be validated with prospective clinical and pharmacokinetic studies to confirm safety and efficacy.

The Efficacy of Low-Dose Paclitaxel Added to Combination Chemotherapy of Carboplatin and Gemcitabine or Pegylated Liposomal Doxorubicin

OBJECTIVE

Paclitaxel is known to produce the "platelet-sparing effect" that prevents the carboplatin-induced decrease in platelet count. We conducted a pilot study to assess whether the addition of low-dose paclitaxel to carboplatin-based combination chemotherapy prevents thrombocytopenia.

METHODS

Patients with platinum-sensitive recurrent ovarian cancer received intravenous (IV) paclitaxel at 60 mg/m(2) followed by IV carboplatin at an area under the curve of 6 and IV pegylated liposomal doxorubicin at 30 mg/m(2) on day 1 in a 28-day cycle (DC-LOP) or IV gemcitabine at 1000 mg/m(2) on days 1 and 8 in a 21-day cycle (GC-LOP).

RESULTS

During May 2011 to December 2011, 7 patients received 29 cycles of DC-LOP; during January 2012 to May 2013, 15 patients received 88 cycles of GC-LOP. Grade 3/4 thrombocytopenia occurred in 2 (33%) of 6 and 9 (56%) of 16 patients in the DC-LOP and GC-LOP groups, respectively. No grade 3/4 nonhematological toxicity was observed. Only one patient who received GC-LOP had grade 2 sensory and motor peripheral neuropathy. Paclitaxel-related toxicities, including muscle pain, arthralgia, and peripheral neuropathy, were consistently rare and mild. The response rates of DC-LOP and GC-LOP were 33% (0, complete response; 2, partial response; 3, stable disease; 1, progression disease) and 50% (2, complete response; 6, partial response; 7, stable disease; 1, progression disease), respectively.

CONCLUSIONS

Although low-dose paclitaxel addition did not alleviate thrombocytopenia in the setting of this pilot study, the results do not deny the existence of the "platelet-sparing effect" by low-dose paclitaxel. Further investigation of the carboplatin-based combination chemotherapy including a drug with mild hematological toxicity is warranted.

Polymorphisms in SLCO1B3 and NR1I2 as genetic determinants of hematotoxicity of carboplatin and paclitaxel combination

Aim: The goal of our study was to assess the impact of patients’ genetic background on their sensitivity to carboplatin/paclitaxel hematotoxicity. Patients & methods: Parameters describing sensitivity to neutropenia and to thrombocytopenia of 201 patients were extracted from a previous pharmacokinetic/pharmacodynamics analysis, in order to assess their association with 52 candidates SNPs in 18 genes. Results: Carriers of a T allele of SLCO1B3-rs4149117 were 19% less sensitive to thrombocytopenia than the homozygotes for the G allele (p = 0.00279). Carriers of two copies of the ATG haplotypes of NR1I2-rs1523130, rs3814055 and rs1523127 were 19% less sensitive to thrombocytopenia than those harboring other haplotypes (p = 0.025). Conclusion: Our results revealed the importance of SLCO1B3 and NR1I2 in the sensitivity to carboplatin/paclitaxel thrombocytopenia.

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.

Do children have the same vulnerability to metabolic drug–drug interactions as adults? A critical analysis of the literature

Many drug–drug interactions (DDIs) in the pediatric population are managed based on data generated in adults. However, due to developmental changes in elimination pathways from birth to adolesence, and variable weight‐adjusted dose of interacting drugs, the assumption of DDIs being similar in adults and pediatrics might not be correct. This study compares the magnitude of reported DDIs in pediatric and adult populations. A systematic literature review was undertaken to identify reports of DDIs in pediatric subjects. A total of 145 reports of DDIs were identified over the age range of birth to 20 years. The magnitude of DDIs for 24 drug pairs from 31 different pediatric studies could be assessed and compared with those in adults where corresponding data existed. The magnitude of the DDI, as measured by a relevant parameter (e.g., AUC, CL) in the presence and absence of inhibitor,were higher (>1.25‐fold), similar (0.8‐ to 1.25‐fold) or lower (<0.8‐fold) than the corresponding ratio in adults in 10, 15, and 8 cases respectively. An age‐related trend in the magnitude of DDIs could not be established. However, the study highlighted the clear paucity of the data in children younger than 2 years. Care should be exercised when applying the knowledge of DDIs from adults to children younger than 2 years of age.

Prospective evaluation of pharmacokinetically guided dosing of carboplatin in Japanese patients with cancer

The Calvert formula, that is, carboplatin dose (mg) = target area under the concentration versus time curve (AUC) × (glomerular filtration rate [GFR] + 25), has not been validated in Japanese subjects in whom the GFR was accurately measured. The purpose of this study is to evaluate the validity of this formula for Japanese patients with cancer and modify it for this population. The GFR was measured on the basis of inulin clearance, which is considered to reflect the accurate GFR. Inulin clearance was measured in 28 patients with cancer. The adjusted 24-h creatinine clearance (24-h Ccr) was unbiased (mean prediction error [MPE] ± SE = -2.3 ± 4.5%) and acceptably precise (root mean squared error = 23.7%) for GFR assessment. The pharmacokinetics of carboplatin were analyzed in 21 patients with a GFR of 17.2-91.4 mL/min. The original Calvert formula overestimated carboplatin clearance, resulting in an MPE of 14.3%. When we revised the Calvert formula for Japanese patients by substituting a non-renal clearance of 15 for 25, that is, dose = target AUC × (GFR + 15), the MPE decreased to -0.1% (P < 0.001). We conclude that the adjusted 24-h Ccr is acceptably precise for GFR assessment, and the non-renal clearance of carboplatin is suggested to be lower in Japanese patients with cancer than in their Western counterparts.

Clinical trials and progress with paclitaxel in ovarian cancer

Paclitaxel is a front-line agent for ovarian cancer chemotherapy, along with the platinum agents. Derived from the Pacific yew tree, Taxus brevifolia, paclitaxel has covered significant ground from the initial discovery of its antineoplastic properties to clinical applications in many forms of human cancers, including ovarian cancer. Although much has been published about the unique mechanism of action of this agent, several issues remain to be resolved. Finding the appropriate dosage schedule for paclitaxel in chemo-naïve and recurrent ovarian cancer, defining the role of paclitaxel in maintenance chemotherapy, and elucidating the mechanisms of taxane resistance are areas of intense research. Newer forms of taxanes are being manufactured to avoid troublesome adverse effects and to improve clinical efficacy. These issues are reviewed in detail in this paper with an emphasis on clinically relevant evidence-based information.

Factors for hematopoietic toxicity of carboplatin: refining the targeting of carboplatin systemic exposure

PURPOSE

Area under the curve (AUC) dosing is routinely carried out for carboplatin, but the chosen target AUC values remain largely empirical. This multicenter pharmacokinetic-pharmacodynamic (PK-PD) study was performed to determine the covariates involved in the interindividual variability of carboplatin hematotoxicity that should be considered when choosing individual target AUCs.

PATIENTS AND METHODS

Three hundred eighty-three patients received carboplatin as part of established regimens. A semi-physiologic population PK-PD model was applied to describe separately the time course of absolute neutrophil and platelet counts using NONMEM software. The plasma ultrafiltrable carboplatin concentration (C(Carbo)) was assumed to inhibit the proliferation of blood cell precursors through a linear model: drug effect = slope × C(Carbo). The slope corresponds to the patients' sensitivity to carboplatin hematotoxicity. The relationships between the patients' sensitivity to the neutropenic or thrombopenic effects of carboplatin and various covariates, including associated chemotherapies, demographic, biologic, and pharmacogenetic data, were studied.

RESULTS

The sensitivity of carboplatin-induced thrombocytopenia decreased in the case of concomitant paclitaxel chemotherapy (slope decreased by 24%), whereas it increased with coadministration of etoposide and gemcitabine (slope increased by 45% and 133%, respectively). For neutropenia, the sensitivity increased when carboplatin was combined with other cytotoxics (slope increased by 76%).

CONCLUSION

This study provides useful information to clinicians to better estimate the hematopoietic toxicity of carboplatin and thus choose more rationally carboplatin target AUCs as a function of pretreatment or concomitantly administered chemotherapies. For example, an AUC of 5 mg/mL · min is associated with a risk of grade 3 or 4 thrombocytopenia of 2% in combination with paclitaxel versus 38% with gemcitabine in a non-pretreated patient.

Dose-escalating and pharmacokinetic study of a weekly combination of paclitaxel and carboplatin for inoperable non-small cell lung cancer: JCOG 9910-DI

OBJECTIVE

Combined paclitaxel and carboplatin is a standard regimen for inoperable non-small cell lung cancer (NSCLC). Although an every-3-week schedule is common, weekly paclitaxel is clinically effective for various cancers. A Phase I clinical trial was conducted to determine maximum-tolerated doses (MTDs) for weekly combined paclitaxel and carboplatin, and to evaluate anti-tumor response, toxicity and pharmacokinetics of paclitaxel in patients with inoperable NSCLC.

METHODS

Twenty patients with inoperable NSCLC received weekly carboplatin at area under the curve (AUC) = 2 mg/ml min and paclitaxel. Paclitaxel was escalated if MTD was not reached. Three patients each were entered at levels 1 and 2 (level 1, paclitaxel 50 mg/m(2) and carboplatin AUC = 2 mg/ml min; level 2, 60/2), six at level 3 (70/2), five at level 4 (80/2) and three at level 5 (90/2).

RESULTS

One patient had grade 4 (G4) neutropenia at level 2, one had G3 hepatic toxicity at level 3 and one had G3 cardiac toxicity at level 4. MTD was not reached for all dose levels. Response rate (RR) was 35% (7/20) and median survival was 11.1 months. Severe neutropenia (G3 and G4) was seen in seven patients associated with greater AUC, peak concentration (C(max)) and the duration of plasma concentration >50 ng/ml of paclitaxel.

CONCLUSIONS

Weekly combined paclitaxel (up to 90 mg/m(2)) and carboplatin (AUC = 2 mg/ml min) was well tolerated. A higher dose intensity of paclitaxel can be given, and RR and survival are not less than the every-3-week protocol. The weekly regimen is an alternative for untreated inoperable NSCLC patients.

Paclitaxel poliglumex and carboplatin as first-line therapy in ovarian, peritoneal or fallopian tube cancer: a phase I and feasibility trial of the Gynecologic Oncology Group

PURPOSE

To estimate the maximum tolerated dose (MTD) of paclitaxel poliglumex (PPX) in combination with carboplatin in patients with chemotherapy-naive ovarian, primary peritoneal or fallopian tube cancer, and to assess the feasibility of administering multiple cycles of this regimen.

METHODS

The first 11 patients were treated in a standard 3 + 3 dose-seeking design, with carboplatin held constant at area under the curve (AUC) of 6 and PPX at 225, 175 or 135 mg/m(2). Pharmacokinetics of PPX and carboplatin were evaluated during this dose-seeking component of the trial. MTD was defined by acute dose-limiting toxicities (DLT) in the first cycle. Twenty additional evaluable patients were treated at the estimated MTD to assess the feasibility of this regimen over >or=4cycles.

RESULTS

PPX at 225 mg/m(2) resulted in DLT in 2/3 patients, and was de-escalated first to 175 mg/m(2) and then to 135 mg/m(2). PPX slowly hydrolyzed to paclitaxel and did not alter the pharmacokinetics of carboplatin. DLT within the first 4-cycles were observed in 3 patients (15%) treated at the MTD: neutropenia > 2weeks (2), febrile neutropenia (1). Nineteen patients (95%) experienced grade 4 neutropenia. Sixteen patients (80%) had at least one episode of grade 3 thrombocytopenia. Three patients (15%) had grade 2 and one had grade 3 peripheral neuropathy. Complete response by CA-125 was 75%.

CONCLUSIONS

The recommended dose of PPX of 135 mg/m(2) with carboplatin (AUC = 6) in newly diagnosed ovarian cancer was feasible for multiple cycles, but hematologic toxicity was greater compared with standard carboplatin and 3-hour paclitaxel.

Population pharmacokinetics and pharmacodynamics of paclitaxel and carboplatin in ovarian cancer patients: a study by the European organization for research and treatment of cancer-pharmacology and molecular mechanisms group and new drug development group

PURPOSE

Paclitaxel and carboplatin are frequently used in advanced ovarian cancer following cytoreductive surgery. Threshold models have been used to predict paclitaxel pharmacokinetic-pharmacodynamics, whereas the time above paclitaxel plasma concentration of 0.05 to 0.2 micromol/L (t(C > 0.05-0.2)) predicts neutropenia. The objective of this study was to build a population pharmacokinetic-pharmacodynamic model of paclitaxel/carboplatin in ovarian cancer patients.

EXPERIMENTAL DESIGN

One hundred thirty-nine ovarian cancer patients received paclitaxel (175 mg/m(2)) over 3 h followed by carboplatin area under the concentration-time curve 5 mg/mL*min over 30 min. Plasma concentration-time data were measured, and data were processed using nonlinear mixed-effect modeling. Semiphysiologic models with linear or sigmoidal maximum response and threshold models were adapted to the data.

RESULTS

One hundred five patients had complete pharmacokinetic and toxicity data. In 34 patients with measurable disease, objective response rate was 76%. Neutrophil and thrombocyte counts were adequately described by an inhibitory linear response model. Paclitaxel t(C > 0.05) was significantly higher in patients with a complete (91.8 h) or partial (76.3 h) response compared with patients with progressive disease (31.5 h; P = 0.02 and 0.05, respectively). Patients with paclitaxel t(C > 0.05) > 61.4 h (mean value) had a longer time to disease progression compared with patients with paclitaxel t(C > 0.05) < 61.4 h (89.0 versus 61.9 weeks; P = 0.05). Paclitaxel t(C > 0.05) was a good predictor for severe neutropenia (P = 0.01), whereas carboplatin exposure (C(max) and area under the concentration-time curve) was the best predictor for thrombocytopenia (P < 10(-4)).

CONCLUSIONS

In this group of patients, paclitaxel t(C > 0.05) is a good predictive marker for severe neutropenia and clinical outcome, whereas carboplatin exposure is a good predictive marker for thrombocytopenia.

Pemetrexed combined with paclitaxel in patients with advanced or metastatic non-small-cell lung cancer: A phase I-II trial

Pemetrexed, a novel multi-targeted agent established for the treatment of mesothelioma, has been under investigation for other malignancies, and in recent years particularly for non-small-cell lung cancer (NSCLC). In the present trial we investigated pemetrexed in combination with paclitaxel as front-line treatment in advanced or metastatic NSCLC. Our objectives were to determine the response rate, median and overall survival and toxicity. From April 2005 until May 2006, 51 patients with advanced or metastatic NSCLC were enrolled and 48 were considered evaluable. There were 39 males and nine females, median age 62 years (range 37-81 years), one patient stage IIIA N(2), 23 patients, IIIB and 24, stage IV. All patients had a cytologically- or histologically-confirmed diagnosis. Pemetrexed was administered at a standard dose of 500mg/m(2) and paclitaxel at an escalating dose starting at 135mg/m(2), then 150mg/m(2) and ending at a dose of 175mg/m(2); the level was increased every three patients. Both agents were administered on day 1, repeated every 3 weeks for six courses. A 39.6% partial response rate was observed with a median survival of 14 months. Toxicity was mild with 8.3% grade 3 and 4 neutropenia and other very mild hematologic and non-hematologic adverse reactions. The combination of pemetrexed and paclitaxel at doses of 500mg/m(2) and 175mg/m(2), respectively, has been shown to be an effective combination with very limited toxicity.

Phase I and pharmacokinetic study of vorinostat, a histone deacetylase inhibitor, in combination with carboplatin and paclitaxel for advanced solid malignancies

PURPOSE

The primary objective of this study was to determine the recommended phase II doses of the novel histone deacetylase inhibitor vorinostat when administered in combination with carboplatin and paclitaxel.

EXPERIMENTAL DESIGN

Patients (N = 28) with advanced solid malignancies were treated with vorinostat, administered orally once daily for 2 weeks or twice daily for 1 week, every 3 weeks. Carboplatin and paclitaxel were administered i.v. once every 3 weeks. Doses of vorinostat and paclitaxel were escalated in sequential cohorts of three patients. The pharmacokinetics of vorinostat, its metabolites, and paclitaxel were characterized.

RESULTS

Vorinostat was administered safely up to 400 mg qd or 300 mg bd with carboplatin and paclitaxel. Two of 12 patients at the 400 mg qd schedule experienced dose-limiting toxicities of grade 3 emesis and grade 4 neutropenia with fever. Non-dose-limiting toxicity included nausea, diarrhea, fatigue, neuropathy, thrombocytopenia, and anemia. Of 25 patients evaluable for response, partial responses occurred in 11 (10 non-small cell lung cancer and 1 head and neck cancer) and stable disease occurred in 7. Vorinostat pharmacokinetics were linear over the dose range studied. Vorinostat area under the concentration versus time curve and half-life increased when vorinostat was coadministered with carboplatin and paclitaxel, but vorinostat did not alter paclitaxel pharmacokinetics.

CONCLUSIONS

Both schedules of vorinostat (400 mg oral qd x 14 days or 300 mg bd x 7 days) were tolerated well in combination with carboplatin (area under the concentration versus time curve = 6 mg/mL x min) and paclitaxel (200 mg/m(2)). Encouraging anticancer activity was noted in patients with previously untreated non-small cell lung cancer.

A phase I study evaluating the safety and pharmacokinetics of weekly paclitaxel and carboplatin in relapsed ovarian cancer

This phase I study sought to determine the toxicity profile, pharmacokinetics, and antitumor activity of giving carboplatin every 3 weeks and paclitaxel weekly in patients with relapsed ovarian cancer. Eligible patients with relapsed epithelial ovarian cancer and prior treatment with platinum- and paclitaxel-based therapy were treated with an escalating regimen of carboplatin (day 1) at an area under the curve (AUC) of 4-6 and 1-h infusions of paclitaxel (days 1, 8, and 15) at 50-80 mg/m(2) cycled at 3-week intervals. Pharmacokinetic studies were performed on the first day of cycles 1 and 2. All patients had a platinum-free interval of greater than 6 months from the most recent platinum treatment. A total of 77 cycles were administered to 16 patients, with a similar median number of cycles per patient at each dose level varying from 4.6 to 5.3. Febrile neutropenia and grade 4 thrombocytopenia were the dose-limiting toxicities at dose levels 3 and 4 after the third cycle, with no mucositis, nausea, vomiting, or peripheral neuropathy observed greater than grade 2. The maximum tolerated dose of carboplatin was an AUC of 5 and 80 mg/m(2) for paclitaxel. Pharmacokinetic analysis showed a marginal statistical difference with regard to reduced systemic paclitaxel concentration after cycle 2 compared with cycle 1 (P= 0.06). Of nine patients evaluable for a radiographic response, the response rate was 66.6% with a complete response of 33.3%. All five patients with nonmeasurable disease achieved a biochemical response. The combination of carboplatin given every 3 weeks at an AUC of 5 and 1-h weekly paclitaxel at 80 mg/m(2) is a feasible and reasonably well-tolerated regimen and may have significant antitumor activity in relapsed ovarian cancer patients.

Paclitaxel-carboplatin combination chemotherapy in advanced breast cancer: accumulating evidence for synergy, efficacy, and safety

Patients with metastatic breast cancer receive multiple lines of cytotoxic chemotherapy, with taxane and anthracycline-based regimens being the most active. Anthracyclines carry the risk of significant cardiotoxicity at high cumulative doses and when combined with trastuzumab, an anti-HER2 antibody. Carboplatin has shown promising single-agent activity in advanced breast cancer, is not a P-glycoprotein substrate, and is conveniently administered on an outpatient basis. Preclinical experiments demonstrated schedule-dependent synergistic cytotoxic effects of the paclitaxel first/carboplatin last (PC) combination. Pharmacokinetic parameters of paclitaxel and carboplatin were studied by Hellenic Cooperative Oncology Group (HECOG) and no significant interaction or correlation with clinical parameters were found. We assessed PC both as salvage as well as first-line treatment of advanced breast cancer patients in phase II studies which disclosed 40-60% response rates and median survival times of 12-20 mo with manageable toxicity. These results were confirmed by other groups and prompted us to the first randomized phase III trial comparing PC to the standard of epirubicin/paclitaxel (EP), a trial that showed equivalent efficacy and tolerable toxicity for PC. Registry retrospective analysis identified factors prognostic for improved outcome: good performance status, low tumor burden, lack of anthracycline exposure and of hormonal maintenance therapy. PC combinations with HER1 or HER2 modulators are being evaluated both by HECOG and by international groups. Paclitaxel coupled with carboplatin provides an alternative therapeutic option for anthracycline-exposed patients and warrants further clinical research in the direction of anthracycline-free management of metastatic breast cancer.

Drug interactions in cancer therapy

Drug interactions in oncology are of particular importance owing to the narrow therapeutic index and the inherent toxicity of anticancer agents. Interactions with other medications can cause small changes in the pharmacokinetics or pharmacodynamics of a chemotherapy agent that could significantly alter its efficacy or toxicity. Improvements in in vitro methods and early clinical testing have made the prediction of potentially clinically significant drug interactions possible. We outline the types of drug interaction that occur in oncology, the mechanisms that underlie these interactions and describe select examples.

Front-line paclitaxel and topotecan chemotherapy in advanced or metastatic non-small-cell lung cancer: a phase II trial

PURPOSE

Based on previous experience, we combined topotecan with paclitaxel (weekly administration) in patients with non-small-cell lung cancer (NSCLC). Our primary objective was to determine the response rate and survival and our secondary objective, the safety of the regimen.

METHODS

From October 2003, until March 2005, 45 patients all with histologically or cytologically confirmed NSCLC were enrolled. All patients were chemotherapy and radiotherapy naive. Both agents were infused on day 1 of every week once for three consecutive weeks, every 28 days. Three infusions were considered as one course. The treatment plan was to give three courses (nine infusions) and then to evaluate the response. Topotecan (1.75 mg/m2) was infused for 30 min and paclitaxel (70 mg/m2) for 90 min; these doses had been established as the maximum tolerated dose in a previous phase I-II trial.

RESULTS

Eighteen/45 (40%) patients responded, 2 (4.4%) complete responses and 16 (35.6%) partial responses. Twenty-one (46.7%) patients had stable disease, and 6 (13.3%) disease progression. The median duration of response was 8 months and median time to tumor progression 9 months. Grade 3 and 4 neutropenia was observed in two patients (in these two patients, the dose of both drugs was reduced by 25% and G-CSF was given), grade 4 thrombocytopenia in one patient and grade 4 anemia in one patient.

CONCLUSION

This novel combination of topotecan-paclitaxel in a weekly administration rendered a 40% response rate, with very low toxicity in stages IIIA, IIIB and IV NSCLC patients.

Phase I study of the taxane BMS-188797 in combination with carboplatin administered every 3 weeks in patients with solid malignancies

RATIONALE

BMS-188797 is one of several novel taxanes in ongoing clinical development. It has superior activity in experimental tumor models when compared with paclitaxel. BMS-188797 has a single C-4 modification, a 4-desacetyl-4-methylcarbonate, compared with paclitaxel.

METHODS

We did a phase I study, in which a fixed dose of carboplatin was combined with a dose escalation schedule of BMS-188797, both administered once every 3 weeks, in patients with advanced solid malignancies.

RESULTS

Thirty patients were treated, 11 at the proposed recommended phase II dose. The dose-limiting toxicity was myelosuppression. There was a linear relationship between administered dose of BMS-188797 and the measured area under the curve (AUC). There was significant interpatient variability of BMS-188797 AUC at the maximum tolerated dose. Two radiographic partial responses were observed: one patient with duodenal adenocarcinoma and one patient with esophageal adenocarcinoma (time on study, 19 and 30 weeks, respectively).

CONCLUSION

The recommended phase II dose for BMS-188797 and carboplatin administered on a once-every-3 week schedule is carboplatin AUC = 5 mg min/mL and BMS-188797 at a dose of 135 mg/m(2).

Pharmacokinetics of paclitaxel in ovarian cancer patients and genetic polymorphisms of CYP2C8, CYP3A4, and MDR1

Interindividual differences in the pharmacokinetics of paclitaxel and its metabolites in Japanese ovarian cancer patients were investigated in relation to genetic polymorphisms of the CYP2C8, CYP3A4, and MDR1 genes. The area under the concentration-time curve (AUC) ratios of paclitaxel/6alpha-hydroxypaclitaxel and paclitaxel/3 -p-hydroxypaclitaxel calculated as the metabolic index of CYP2C8 and CYP3A4 showed 13- and 12-fold interindividual variations, respectively. No patient had any CYP2C8 variants, while 2 patients were heterozygotes of CYP3A4*16. For the MDR1 gene, the frequencies of -129C, 1236C, 2677T, 2677A, and 3435T alleles were 2.2%, 8.7%, 56.5%, 4.4%, and 52.2%, respectively. Subjects possessing the 3435T allele had a significantly (P < .05) higher AUC of 3'- p-hydroxypaclitaxel compared to those possessing the 3435C allele. Leukocytopenia was significantly (P < .05) related to the AUC of paclitaxel. Genotyping of the CYP2C8, CYP3A4, and MDR1 genes might not be essential to predict adverse effects of paclitaxel in Japanese patients, although an allelic variant of MDR1 may functionally affect the pharmacokinetics of its metabolite.

A multicenter phase II study of carboplatin and paclitaxel with a biweekly schedule in patients with advanced non-small-cell lung cancer: Kyushu thoracic oncology group trial

PURPOSE

This multicenter phase II study was conducted to investigate the efficacy and safety of carboplatin in combination with paclitaxel administered according to a biweekly schedule as a first-line chemotherapy for advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Eligibility criteria included histologically or cytologically confirmed NSCLC (stage IIIb or IV), no prior treatment, and measurable or evaluable disease. Paclitaxel (140 mg/m(2)) was administered intravenously on day 1, in combination with carboplatin at an area under the concentration time curve (AUC) of 3, every 2 weeks.

RESULTS

Seventy-four patients (45 men) with a median age of 62 years (range 40-74) and a median ECOG performance status of 1 (range 0-2) were enrolled. The response rate was 35.1% [95% confidence interval (CI): 24.4-47.1%], with 26 partial responses. The median survival was 357 days, and the median time to progression was 218 days. Toxicity was generally mild; National Cancer Institute-Common Toxicity Criteria (NCI-CTC) grades 3 and 4 neutropenia was observed in 50.0% of the patients, and grades 3 and 4 nausea/vomiting in 4.1%.

CONCLUSIONS

Biweekly carboplatin combined with paclitaxel demonstrated anti-tumor activity in advanced NSCLC, with response and survival rates similar to those of carboplatin combined with paclitaxel administered every 3 weeks but with a more favorable toxicity profile, and the present data indicate that the regimen is suitable for use on an outpatient basis.

Front-line paclitaxel and irinotecan combination chemotherapy in advanced non-small-cell lung cancer: a phase I-II trial

Our purpose was to determine the efficacy of irinotecan plus paclitaxel administered on day 1, repeated every 2 weeks, in untreated patients with advanced or metastatic non-small-cell lung cancer (NSCLC). In total, 56 patients with inoperable or metastatic stage III and IV NSCLC with a histologically or cytologically confirmed diagnosis were enrolled. None of the patients had undergone prior chemotherapy or radiation therapy. Treatment involved irinotecan 125 mg m⁻² and paclitaxel 135 mg m⁻² administered on day 1 and repeated every 2 weeks for a planned number of nine cycles. With a standard dose of paclitaxel at 135 mg m⁻², the dosage of irinotecan was escalated at four levels: 75, 100, 125 and 150 mg m⁻²; 125 mg m⁻² was established as the maximum tolerated dose; this dosage was administered to 46 patients. A total of 52 patients (median age 65 years, range 38–77 years) were assessable for toxicity and survival and 46 for response rate. Out of 46 evaluable patients, 19 achieved partial response (41.3%), 17 had stable disease (37%) and 10 (21.7%) experienced disease progression. The median duration of response was 6 months (range 2–9+ months). The main adverse reactions were myelotoxicity (grades 3 and 4) in 10 (19.2%) patients and diarrhoea (grade 3) in four (7.7%) patients. Irinotecan combined with paclitaxel, administered every 2 weeks, appears to be an effective treatment for advanced-stage NSCLC.

Phase I trial of the matrix metalloproteinase inhibitor marimastat combined with carboplatin and paclitaxel in patients with advanced non-small cell lung cancer

PURPOSE

Marimastat is an orally bioavailable inhibitor of matrix metalloproteinases. A phase I study was initiated to determine whether conventional doses of carboplatin and paclitaxel are tolerated when combined with marimastat and to assess the influence of marimastat on paclitaxel pharmacokinetics.

EXPERIMENTAL DESIGN

Three dose levels were evaluated. Marimastat (10 or 20 mg oral administration b.i.d.) was administered continuously with paclitaxel (175 or 200 mg/m(2) as a 3-hour i.v. infusion) and carboplatin (at a dose providing an area under the free drug plasma concentration-time curve of 7 mg min/mL) administered each 3 weeks. Toxicity and response were evaluated throughout the intended four cycles of combined therapy. The plasma pharmacokinetics of paclitaxel was determined in each patient both without concurrent marimastat and after receiving marimastat for 1 week.

RESULTS

Twenty-two chemotherapy-naive patients with stage IIIb (27%) or stage IV (73%) non-small cell lung cancer were enrolled. Their median age was 56 years (range, 39-73 years), 50% were female, and their performance status (Eastern Cooperative Oncology Group) ranged from 0 to 2. Treatment was well tolerated, as 18 (82%) of the patients completed all four cycles of chemotherapy without dose-limiting toxicity. Grade 2 musculoskeletal toxicities were reported in 3 of 12 patients receiving marimastat (20 mg b.i.d.). Nine patients required dose reductions, predominantly related to low-grade myelosuppression. Partial responses occurred in 12 of 21 (57%) evaluable patients with disease stabilization in another 5 (19%). Marimastat had no effect on paclitaxel pharmacokinetics.

CONCLUSIONS

The administration of marimastat (10 mg b.i.d.) with paclitaxel (200 mg/m(2)) and carboplatin at an area under the free drug plasma concentration-time curve of 7 mg min/mL was well tolerated with no apparent pharmacokinetic interaction. Study of this drug combination in the adjuvant setting should be considered if tissue inhibition of matrix metalloproteinase activity can first be shown.

Paclitaxel chemotherapy: from empiricism to a mechanism-based formulation strategy

Paclitaxel is an anticancer agent effective for the treatment of breast, ovarian, lung, and head and neck cancer. Because of water insolubility, paclitaxel is formulated with the micelle-forming vehicle Cremophor EL to enhance drug solubility. However, the addition of Cremophor EL results in hypersensitivity reactions, neurotoxicity, and altered pharmacokinetics of paclitaxel. To circumvent these unfavorable effects resulting from the addition of Cremophor EL, efforts have been made to develop new delivery systems for paclitaxel administration. For example, ABI-007 is a Cremophor-free, albumin-stabilized, nanoparticle paclitaxel formulation that was found to have significantly less toxicity than Cremophor-containing paclitaxel in mice. Pharmacokinetic studies indicate that in contrast to Cremophor-containing paclitaxel, ABI-007 displays linear pharmacokinetics over the clinically relevant dose range of 135-300 mg/m(2). In a phase III study conducted in patients with metastatic breast cancer, patients treated with ABI-007 achieved a significantly higher objective response rate and time to progression than those treated with Cremophor-containing paclitaxel. Together these findings suggest that nanoparticle albumin-bound paclitaxel may enable clinicians to administer paclitaxel at higher doses with less toxicity than is seen with Cremophor-containing paclitaxel. The role of this novel paclitaxel formulation in combination therapy with other antineoplastic agents needs to be determined.

Randomized phase III trial comparing cisplatin-etoposide to carboplatin-paclitaxel in advanced or metastatic non-small cell lung cancer

BACKGROUND

The present study was designed to evaluate the efficacy and safety of the regimen of carboplatin plus paclitaxel (investigational arm) versus the reference regimen of cisplatin plus etoposide for the treatment of advanced or metastatic non-small-cell lung cancer.

PATIENTS AND METHODS

A total of 369 patients were enrolled, 179 on arm A (cisplatin 75 mg/m2 and etoposide 100 mg/m2) and 190 on arm B (carboplatin AUC=6 mg/ml min and paclitaxel 225 mg/m2), with cycles repeated every 3 weeks. The arms were well balanced with respect to age, performance status, weight loss, stage of disease and disease measurability. However, significantly more women were randomized to arm A than to arm B (P=0.039).

RESULTS

The objective response rate (ORR) was 15% on arm A compared with 23% on arm B (P=0.061). Median survival time, time to progression and 1-year survival rates for arms A and B were 274 days and 233 days (P=0.086), 111 days and 121 days (P=0.877), and 37% and 32%, respectively. The most prevalent toxicities were neutropenia and leukopenia and they occurred at a higher rate in arm A than in arm B.

CONCLUSION

There was no statistically significant survival advantage for carboplatin-paclitaxel compared with cisplatin-etoposide. However, there was an overall benefit in quality of life with the carboplatin-paclitaxel regimen.

Phase I Trial of Combretastatin A-4 Phosphate with Carboplatin

PURPOSE

Preclinical evidence of synergy led to a phase I trial employing combretastatin A-4 phosphate (CA4P), a novel tubulin-binding antivascular drug, in combination with carboplatin.

EXPERIMENTAL DESIGN

Based on preclinical scheduling studies, patients were treated on day 1 of a 21-day cycle. Carboplatin was given as a 30-minute i.v. infusion and CA4P was given 60 minutes later as a 10-minute infusion.

RESULTS

Sixteen patients with solid tumors received 40 cycles of therapy at CA4P doses of 27 and 36 mg/m(2) together with carboplatin at area under the concentration-time curve (AUC) values of 4 and 5 mg min/mL. The dose-limiting toxicity of thrombocytopenia halted the dose escalation phase of the study. Four patients were treated at an amended dose level of CA4P of 36 mg/m(2) and carboplatin AUC of 4 mg min/mL although grade 3 neutropenia and thrombocytopenia were still observed. Three lines of evidence are adduced to suggest that a pharmacokinetic interaction between the drugs results in greater thrombocytopenia than anticipated: the carboplatin exposure (as AUC) was greater than predicted; the platelet nadirs were lower than predicted; and the deviation of the carboplatin exposure from predicted was proportional to the AUC of CA4, the active metabolite of CA4P. Patient benefit included six patients with stable disease lasting at least four cycles.

CONCLUSION

This study of CA4P and carboplatin given in combination showed dose-limiting thrombocytopenia. Pharmacokinetic/pharmacodynamic modeling permitted the inference that altered carboplatin pharmacokinetics caused the increment in platelet toxicity.

Results of paclitaxel (day 1 and 8) and carboplatin given on every three weeks in advanced (stage III-IV) non-small cell lung cancer

Background

Both paclitaxel (P) and carboplatin (C) have significant activity in non-small cell lung cancer (NSCLC). The weekly administration of P is active, dose intense, and has a favorable toxicity profile. We retrospectively reviewed the data of 51 consecutive patients receiving C and day 1 and 8 P chemotherapy (CT) regimen in advanced stage NSCLC to evaluate the efficacy and toxicity.

Methods

Patients treated in our institutions having pathologically proven NSCLC, no CNS metastases, adequate organ function and performance status (PS) ECOG 0–2 were given P 112.5 mg/m² intravenously (IV) over 1 hour on day 1 and 8, followed by C AUC 5 IV over 1 hour, repeated in every three weeks. PC was given for maximum of 6 cycles.

Results

Median age was 58 (age range 39–77) and 41 patients (80%) were male. PS was 0/1/2 in 29/17/5 patients and stage was IIIA/IIIB/IV in 3/14/34 patients respectively. The median number of cycles administered was 3 (1–6). Seven patients (14%) did not complete the first 3 cycles either due to death, progression, grade 3 hypersensitivity reactions to P or lost to follow up. Best evaluable response was partial response (PR) in 45% and stable disease (SD) in 18%. Twelve patients (24%) received local RT. Thirteen patients (25%) received 2nd line CT at progression. At a median follow-up of 7 months (range, 1–20), 25 (49%) patients died and 35 patients (69%) progressed. Median overall survival (OS) was 11 ± 2 months (95% CI; 6 to 16), 1-year OS ratio was 44%. Median time to progression (TTP) was 6 ± 1 months (95% CI; 4 to 8), 1-year progression free survival (PFS) ratio was 20%. We observed following grade 3 toxicities: asthenia (10%), neuropathy (4%), anorexia (4%), anemia (4%), hypersensitivity to P (2%), nausea/vomiting (2%), diarrhea (2%) and neutropenia (2%). Two patients (4%) died of febrile neutropenia. Doses of CT were reduced or delayed in 12 patients (24%).

Conclusions

P on day 1 and 8 and C every three weeks is practical and fairly well tolerated outpatient regimen. This regimen seems to be comparably active to regimens given once in every three weeks.

Phase I trial of the novel taxane BMS-184476 administered in combination with carboplatin every 21 days

The aim of the study was to determine the maximum-tolerated dose and dose-limiting toxicities for BMS-184476, in combination with carboplatin, in patients with advanced solid tumours and to describe any preliminary antitumour activity associated with this regimen. Patients received combination therapy with BMS-184476 given intravenously over 1 h followed by carboplatin administered over 30 min on day 1 of a 21-day cycle. In all, 28 patients received 146 cycles of BMS-184476 and carboplatin. Patients were enrolled at four dose levels: BMS-184476 (mg m(-2))/carboplatin (mg min ml(-1)): 40/5, 50/5, 50/6 and 60/6. Dose-limiting toxicity at 60/6 was neutropenia. Among 27 evaluable patients, 11 demonstrated stable disease for a median of 8.5 cycles. In 22 patients, the pharmacokinetics of BMS-184476 appeared independent of dose of BMS-184476. The mean+/-s.e.m. values for clearance (Cl), volume of distribution at steady state and apparent terminal half-life of BMS-184476 in the four dose groups during cycle 1 were 192+/-25 ml min m(-2), 377+/-69 l m(-2) and 33.7+/-5.9 h, respectively. An increase in the dose of carboplatin from 5 to 6 mg min ml(-1) may have decreased Cl of BMS-184476. BMS-184476 in combination with carboplatin was well tolerated at a dose of 50/6 and shows evidence of antitumour activity in a pretreated population.

A randomized cross-over trial to determine the effect of Cremophor EL on the pharmacodynamics and pharmacokinetics of carboplatin chemotherapy

PURPOSE

Paclitaxel, when combined with carboplatin, exhibits a platelet-sparing effect. Paclitaxel is formulated in Cremophor EL (CrEL), which has been shown in preclinical models to reduce haematological toxicity from radiotherapy and chemotherapy. We sought to determine the effect of a 3-h infusion of 20 ml/m2 (equivalent to 175 mg/m2 paclitaxel) CrEL on myelosuppression following carboplatin chemotherapy, and the effect of CrEL on carboplatin pharmacokinetics.

METHODS

A total of 16 patients with locally advanced or metastatic cancer were randomized to receive either CrEL or saline over 3 h prior to carboplatin (area under the curve, AUC, 5-7). Each patient was subsequently crossed over to the other treatment. Blood samples were collected at selected time-points for estimation of platinum AUC and 24-h platinum levels. Full blood counts were obtained three times per week.

RESULTS

Of the 16 patients randomized, 15 were evaluable. Myelosuppression was measured by percentage fall at nadir and nadir levels. No significant differences were obtained when comparing CrEL and saline with respect to the above end-points after adjusting for multiple testing. There was no evidence to indicate that CrEL altered the pharmacokinetics of carboplatin.

CONCLUSION

CrEL at this dose and schedule does not appear to be a major contributory factor to the platelet-sparing effect of paclitaxel when combined with carboplatin, nor does it alter the pharmacokinetics of carboplatin.

Front-line paclitaxel–vinorelbine versus paclitaxel–carboplatin in patients with advanced non-small-cell lung cancer: a randomized phase III trial

PURPOSE

This randomized phase III trial of advanced or metastatic non-small-cell lung cancer (NSCLC) was designed to compare a standard treatment such as carboplatin (CRP)-paclitaxel (PCT) with a new combination, vinorelbine (VRL)-PCT-two agents acting in microtubules.

PATIENTS AND METHODS

Three hundred and sixty patients (stage IIIa, IIIb and IV) were included and evaluated for response rate, survival and toxicity. Arm A patients were treated with the control combination of CRP 6 AUC and PCT 175 mg/m(2) repeated every 3 weeks for six cycles, and arm B with the investigational combination of VRL 25 mg/m(2) and PCT 135 mg/m(2) repeated every 2 weeks for nine cycles. The patients were well balanced with respect to gender, disease stage and performance status. Arm A received 849 cycles (mean 4.59 per patient) and arm B 951 cycles (mean 5.39 per patient).

RESULTS

Complete and partial response rates were 45.95% and 42.86% for arms A and B, respectively. Median survival was 11 and 10 months, 1-year survival 42.7% and 37.85% and 2-year survival 10.12% and 19% for arms A and B, respectively. Toxicity was similar in all patients, except for neutropenia, which was significantly greater in arm B.

CONCLUSIONS

PCT combined with VRL produces similar (non-significant) response rates, survival and toxicity (except for neutropenia, as noted above) to standard CRP-PCT treatment in untreated advanced-stage NSCLC.

Toxicity patterns of cytotoxic drugs

Toxicity is a major concern for anticancer drugs. These compounds present a narrow therapeutic index, with a small difference between the dose required for an antitumor effect and that responsible for unacceptable toxicity. Their recommended doses are determined according to the toxicity endpoint. Moreover, toxicity is observed earlier than the therapeutic effect, so, toxic effects represent a major endpoint for pharmacodynamic studies of cytotoxic drugs. Knowledge of toxicity patterns and main factors of toxicity of anticancer drugs is required before modeling data of these studies. Hematological toxicities represent the main toxicity of the cytotoxic. However, non-hematological toxicities have become more important than hematological toxicities as pharmacodynamic endpoints in some circumstances such as high-dose chemotherapy associated with bone marrow transplantation. This paper will describe the main toxicity of the cytotoxic drugs, and its factors of both inter- and intra-patient variability. The toxicity pattern of topotecan will be examined as an example. Knowledge of the toxicity pattern of a drug constitutes a prerequirement before modeling its pharmacodynamics.