Phase II study of gemcitabine (2',2'-difluorodeoxycytidine) given as a twice weekly schedule to previously untreated patients with non-small cell lung cancer

Phase I trial of radiotherapy concurrent with twice-weekly gemcitabine for head and neck cancer: translation from preclinical investigations aiming to improve the therapeutic ratio

BACKGROUND

Once-weekly gemcitabine concurrent with radiotherapy was highly effective in the treatment of head and neck cancer (HNC) but limited by high mucosal toxicity. Pre-clinical investigations suggested that delivering gemcitabine at substantially lower doses twice weekly during radiotherapy improved the therapeutic ratio. We sought to translated these preclinical findings to a phase I trial.

METHODS

Twenty-five patients with non-resectable HNC were scheduled to receive gemcitabine twice weekly during the last 2 weeks (total 5 infusions) of hyperfractionated radiotherapy delivering 1.2 Gy twice daily to total 76.8 Gy. Tumor biopsies to measure active intracellular (phosphorylated) gemcitabine were planned after the first drug delivery. Patients were assigned to escalating dose cohorts using the Continuous Reassessment Method.

RESULTS

Twenty-one patients evaluable for toxicity were divided into cohorts receiving twice weekly treatment with 10, 20, 33, or 50 mg/m(2) gemcitabine. Dose-limiting toxicity was grade 3-4 confluent mucositis/pharyngitis, and the maximally tolerated dose (MTD) was 20 mg/m(2). Median survival was 20 months, with no difference between cohorts receiving lower (10, 20 mg/m(2)) or higher (33, 50 mg/m(2)) gemcitabine doses. Tumor biopsies after the first drug delivery showed only a minority of tumor cells in the specimens.

CONCLUSION

These findings validate preclinical models that show that gemcitabine is radiation sensitizer at doses far below those used for systemic chemotherapy. However, the improvement in the therapeutic ratio predicted from the preclinical study did not translate into a substantial relative increase in the MTD of the drug in the clinical phase I trial.

Comparison of pharmacokinetics, efficacy and toxicity profile of gemcitabine using two different administration regimens in Chinese patients with non-small-cell lung cancer

OBJECTIVE

To conduct a randomized comparative trial of pharmacokinetics, efficacy and toxicity profile treatment with 1200 mg/m(2) gemcitabine using standard 30-min infusion or fixed dose rate (FDR) infusion [10 mg/(m(2) x min)] on days 1 and 8 plus carboplatin AUC (area under curve) 5 on day 1 in Chinese non-small-cell cancer patients. Twelve patients were enrolled in this study.

METHODS

Plasma gemcitabine concentrations were measured by ion-pair reversed phase high performance liquid chromatography. Antitumoral activity and toxicity of gemcitabine was assessed according to World Health Organization criteria.

RESULTS

The obtained mean parameters, such as T(1/2) (elimination half time), AUC, and CL (clearance), were consistent with those reported in literature. Qualified response rate in our study was 33.3% for standard arm and 50% for FDR arm. Additional 50% and 33.3% patients contracted stable disease (SD) in standard arm and FDR arm, respectively. The predominant toxicity was hematologic, and patients in the standard infusion arm experienced consistently more hematologic toxicity.

CONCLUSION

Pharmacokinetic and clinical data in this trial support the continued evaluation of the FDR infusion strategy with gemcitabine.

Pharmacokinetics of gemcitabine in Chinese patients with non-small-cell lung cancer

To determine the pharmacokinetics of gemcitabine (2',2'-difluorodeoxycytidine) in Chinese non-small-cell lung cancer (NSCLC) patients. Six study subjects were administered gemcitabine at a fixed dose rate of 10 mg/m(2) per min (1200 mg/m(2), two hours infusion), and carboplatin and plasma gemcitabine concentrations were measured by ion-pair reversed-phase high-performance liquid chromatography (HPLC). 3P97 Pharmaceutical Kinetics Software was used for the calculation of pharmacokinetic parameters. The obtained mean parameters, elimination half life (t(1/2)) (10.67+/-3.38 min), area under the curve (AUC) (7.55+/-1.53 (microg x h)/ml), and clearance (CL) (3940.05+/-672.08 ml/min), were consistent with those reported in literature. The hematologic toxicology result showed that the regimen was effective on and tolerated by the patients.

Gemcitabine twice weekly as a radiosensitiser for the treatment of brain metastases in patients with carcinoma: a phase I study

Conventional treatment for brain metastases (BM) is whole-brain radiotherapy (WBRT). Efficacy is poor. It might be increased by a potent radiosensitiser such as gemcitabine which is believed to cross the disrupted blood–brain barrier. Primary objective of this study was to determine the maximum tolerated dose (MTD) of twice weekly gemcitabine given concurrently with WBRT. Patients with BM from carcinoma were included. The dose of WBRT was 30 Gys (10 daily fractions). Gemcitabine was given 2–4 h prior to WBRT on days 1 and 8 for the first cohort of patients and then on days 1, 4, 8 and 11. Starting dose was 25 mg m⁻², escalated by 12.5 mg m⁻² increments. At least three patients were included per level. Dose limiting toxicity (DLT) was defined as grade 4 haematological or grade ⩾3 nonhaematological toxicity. A total of 25 patients were included; 74% had a PS 1 (ECOG). In all, 23 had non-small-cell lung cancer, six colorectal, four breast, two renal cell and one oesophageal carcinoma. A total of 92% had concurrent extracranial disease. Six had single BM, 13 had two or three BM and six multiple. Up to 50 mg m⁻² (level 4) no DLT was observed. At 62.5 mg m⁻², one out of six patients developed DLT (thrombocytopenia-bleeding). The next dose level (75 mg m⁻²) was abandoned after grade 4 bone marrow toxicity (fatal neutropenic sepsis) was seen in one out of two patients. So that the dose of 50 mg m⁻² will be taken forward for further study.

Gemcitabine pharmacokinetics and interaction with paclitaxel in patients with advanced non-small-cell lung cancer

PURPOSE

Gemcitabine administered at a fixed dose rate of 10 mg/m(2) per min has been reported to achieve plasma steady-state concentrations ranging from 10 to 20 microM in patients with acute leukemia. These concentrations have been shown to saturate the intracellular accumulation of the active triphosphate metabolite. We designed this pharmacokinetic study to assess the ability of a fixed dose rate of gemcitabine to achieve the desired steady-state concentration in the absence and presence of paclitaxel in patients with solid tumors.

PATIENTS AND METHODS

A group of 14 patients with advanced non-small-cell lung cancer received paclitaxel 110 mg/m(2) over 3 h on days 1 and 8 and gemcitabine 800 mg/m(2) over 80 min on days 1 and 8 every 21 days. Patients received gemcitabine alone on cycle (C) 1, day (D) 1. Pharmacokinetic samples were collected at 0, 15, 30, 45, 60 and 80 min during infusion and 0.25, 0.5, 1, 2, 4, 6, and 8 h after infusion on C1D1, C1D8, C2D1, C4D1 and C6D1.

RESULTS

Of 13 patients included in the pharmacokinetic analysis, 61% achieved the desired steady-state concentration (C(ss)) with gemcitabine alone (C1D1), whereas only 0 to 45% of patients achieved the desired C(ss) with paclitaxel and gemcitabine, depending on the treatment cycle. Paclitaxel significantly decreased systemic clearance (Cl(T); P=0.012) and volume of distribution (V(d); P=0.050) and significantly increased C(ss) ( P=0.009). Gemcitabine plasma pharmacokinetic parameters demonstrated great interpatient variability in the absence of paclitaxel (C(ss) 30%, Cl(T) 30%, V(d) 55%). Interpatient and intrapatient variability in gemcitabine pharmacokinetics were not observed when gemcitabine was administered in combination with paclitaxel (P>0.05).

CONCLUSIONS

Gemcitabine plasma pharmacokinetic parameters are significantly altered in the presence of paclitaxel.

A Bayesian re-assessment of two Phase II trials of gemcitabine in metastatic nasopharyngeal cancer

The Simon two-stage minimax design is a popular statistical design used in Phase II clinical trials. The analysis of the data arising from the design typically involves the use of frequentist statistics. This paper presents an alternative, Bayesian, approach to the design and analysis of Phase II clinical trials. In particular, we consider how a Bayesian approach could have affected the design, analysis and interpretation of two parallel Phase II trials of the National Cancer Centre Singapore, on the activity of gemcitabine in chemotherapy-naïve and in previously treated patients with metastatic nasopharyngeal carcinoma. We begin by explaining the Bayesian methodology and contrasting it with the frequentist approach. We then carry out a Bayesian analysis of the trial results. The conclusions drawn using the Bayesian approach were in general agreement with those obtained from the frequentist analysis. However they had the advantage of allowing for different and potentially more useful interpretations to be made regarding the trial results, as well as for the incorporation of external sources of information. In particular, using a Bayesian trial design, we were able to take into account the results of the parallel trial results when deciding whether to continue each trial beyond the interim stage.

Prospective phase II study of single-agent gemcitabine in untreated elderly patients with stage IIIB/IV non-small-cell lung cancer

The purpose of this study was to evaluate the efficacy and tolerability of single-agent gemcitabine in untreated elderly patients with stage IIIb/IV non-small-cell lung cancer (NSCLC). Since April 1997, 46 consecutive patients have been enrolled in this multicenter study. Gemcitabine 1,000 mg/m2 was administered as a 30-minute intravenous infusion on days 1, 8, and 15 every 28 days. Primary patient characteristics were: male/female 38/8; median age 73 years (range: 70-82 years); median Karnofsky performance status (PS) 90 (range: 70-100); stage IIIb 61% and stage IV 39%; histotype: epidermoid 48%, adenocarcinoma 43%, and large cell carcinoma 9%. No complete response was observed, but 10 (21.7%) patients achieved partial response (PR) (95% confidence limits: 11-36%), 27 (58.7%) had stable disease (SD), and 7 (15%) progressed early (at the first evaluation). The median duration of PR and SD was 8 months (range: 4-23+ months) and 4 months (range: 2-9 months), respectively. Subjective response evaluating PS and symptoms such as dyspnea, pain, and cough was evaluated in 40 patients; 11 (27.5%) improved, 15 (37.5%) remained stable, and 14 (35%) worsened. The median time to progression was 4 months, the median survival was 9 months, and 1-year survival was 44%. After a median follow-up of 10.5 months, 14 patients are still alive. There were no grade 4 toxicities. Grade 3 neutropenia and thrombocytopenia occurred in 19% and 2% of patients, respectively. Nonhematologic toxicities were mild. Grade I/II side effects of nausea/vomiting, transient fever, increase of hepatic transaminases, transient peripheral edema at lower extremity (not related to cardiac or renal disease or phlebothrombosis) were reported. This phase II study confirms the activity and favorable toxicity profile of single-agent gemcitabine in the treatment of elderly patients with advanced NSCLC.

Radiation therapy and concurrent fixed dose amifostine with escalating doses of twice-weekly gemcitabine in advanced pancreatic cancer

PURPOSE

To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of twice-weekly gemcitabine (TW-G) when administered in conjunction with fixed dose amifostine (A) during external radiotherapy (RT) in patients with advanced pancreatic cancer.

METHODS AND MATERIALS

Ten patients with previously untreated, locally advanced, or asymptomatic-metastatic pancreatic adenocarcinoma were enrolled in this study. RT was delivered by using the standard four-field technique (1.8 Gy daily fractions, 45 Gy followed by a boost of 5.4 Gy, in 5-1/2 weeks). The starting dose of TW-G was 60 mg/m(2) (i.v., 30-min infusion), which is equal to the upper limit of previously reported MTD of TW-G when given without A during RT. A was given just before the TW-G, at a fixed dose of 340 mg/m(2) (i.v., rapid infusion). TW-G doses were escalated by 30-mg/m(2) increments in successive cohorts of 3 to 6 additional patients until DLT was observed. Toxicities were graded using the Radiation Therapy Oncology Group and National Cancer Institute Common Toxicity Criteria, version 2.0.

RESULTS

In general, therapy was well tolerated in patients treated at the first two dose levels of 60 mg/m(2) and 90 mg/m(2). The DLT of TW-G given in conjunction with A during RT were neutropenia, thrombocytopenia, and nausea/vomiting at the dose level of 120 mg/m(2). Of the 10 patients eligible for a median follow-up of 10 months, 5 remain alive; 1 complete responder, 3 partial responders, and 1 with stable disease.

CONCLUSION

A dose of TW-G at a level of 90 mg/m(2) produced tolerable toxicity and it may possess significant activity when delivered in conjunction with 340 mg/m(2) dose of A during RT of the upper abdomen. Due to the higher MTD of TW-G seen in our study, we consider that the A supplementation may optimize the therapeutic index of TW-G-based chemoradiotherapy protocols in patients with pancreatic carcinoma.

A phase II trial testing gemcitabine as second-line chemotherapy for non small cell lung cancer. The European Lung Cancer Working Party. 101473.1044@compuserve.com

The purpose of the present trial was to determine the activity of gemcitabine as a second-line chemotherapy for non small cell lung cancer (NSCLC). To be eligible, patients had to have pathologically proven NSCLC that has failed to respond to a first-line chemotherapy with a cisplatin-containing regimen, a Karnofsky performance status greater than 50 and adequate renal, haematological and hepatic functions. After registration, patients were treated by gemcitabine given i.v. at a dose of 1 g/m(2) on days 1, 8, 15 every 4 weeks. Response was assessed after two courses of therapy. Eighty-two patients have been registered, five are ineligible and 65 are assessable for response. Four partial responses were observed (6%). No change was documented in 18 cases (28%). Tolerance was good. A few grade III leucopenia and grade III-IV thrombopenia were observed. We conclude that gemcitabine has a modest activity as second-line chemotherapy for NSCLC. It has the advantage to be well tolerated and may thus be one drug to be proposed to the patients who have disease progression after a first-line chemotherapy and who ask for further treatment.

Metastatic pattern in non-resectable non-small cell lung cancer

This study describes the metastatic pattern at autopsy in patients with non-resectable non-small cell lung cancer (NSCLC) and evaluates the impact of various pretreatment variables and treatment outcomes on the metastatic spread. In eight phase II chemotherapy trials from 1985 through 1993, 337 patients were treated and 51 autopsies were performed (autopsy rate 15%). The male/female ratio was 31/20, median age 56 years (range 36-71), response rate to chemotherapy 8%, and median survival 88 days (range 3-899). Histologic types included adenocarcinoma, 31 cases (60%), squamous cell carcinoma, 9 cases (18%), large cell carcinoma, 9 cases (18%), and unclassified NSCLC, 2 cases (4%). Patients who were autopsied had a shorter median survival than patients without autopsy (p = 0.002, log-rank test). Most commonly involved metastatic sites found at autopsy were mediastinal lymph nodes (84%), pleura (51%), liver (47%), bone (34%), brain (32%), pericardium (29%), adrenals (29%). The median number of involved organs was 5 (range 1-16), with a median of 3 intrathoracic sites (range 1-8) and 2 extrathoracic sites (range 0-11). Patients who initially had metastatic NSCLC also had significantly more metastatic sites at autopsy both extrathoracic (p = 0.004) and totally (p = 0.03) compared to patients with locally advanced disease. No other relation to pretreatment variables was found.

The role of single-agent gemcitabine in the treatment of non-small-cell lung cancer

Gemcitabine is a novel antimetabolite which has shown anti-tumor activity against a variety of tumors including non-small-cell lung cancer (NSCLC). Phase I clinical trials with gemcitabine revealed it was well tolerated and several phase II trials were conducted. This report will summarize the data from 15 phase I-II trials conducted in both untreated and treated patients with advanced lung cancer. Overall, single-agent gemcitabine was active with response rates in untreated patients ranging from 14%-33% and 0%-25% in previously treated patients. Grade 4 toxicities were infrequent with neutropenia reported in 2%-6% of patients and grade 4 thrombocytopenia was rate (1%). One randomized phase III trial comparing the efficacy and safety of gemcitabine to best supportive care confirmed the role of gemcitabine as an active agent for the treatment of NSCLC. Furthermore, gemcitabine was shown in several economic models to be cost-effective. In summary single agent gemcitabine is active, minimally toxic, and cost-effective as a treatment regimen for patients with advanced lung cancer. Studies combining gemcitabine with other active agents are underway and have reported promising results. As monotherapy, gemcitabine may make a valuable contribution to those patients with a poor performance status or comorbid diseases desiring treatment studies in this setting should also be considered.

A phase I study of gemcitabine/cisplatin/etoposide in the treatment of small-cell lung cancer

PURPOSE

To define the maximum tolerated dose and toxicity of combined cisplatin, etoposide, and gemcitabine in patients with small-cell lung cancer.

METHODS

We undertook a phase I study in patients with either extensive small-cell lung cancer with or without prior chemotherapy, or limited disease who had progressed or recurred despite prior treatment. Patients received cisplatin 75 mg/m2 i.v. day 1, etoposide 50-100 mg/m2 i.v. day 1 followed by oral administration of 50-100 mg/m2 days 2 5, and gemcitabine at either 800 or 1000 mg/m2 i.v. days 1 and 8, on a 3 weekly cycle.

RESULTS

We treated 20 patients, 14 at the 800 mg/m2 gemcitabine dose level, and six at the 1000 mg/m2 dose level. The protocol initially used an etoposide dose of 100 mg/m2 etoposide daily (i.v. day 1 and orally days 2-5), but the first two patients died of septic complications. With reduction of the etoposide dose to 50 mg/m2 daily x 5, the regimen was well tolerated. At this etoposide dose, neutropenia, mucositis, and gastrointestinal toxicity occurred in one patient at each of the two gemcitabine dose levels. In addition, one patient receiving gemcitabine at the 1000 mg/m2 level experienced a possible allergic reaction. The overall response rate was 54%. Patients on gemcitabine at the 800 mg/m2 level who had not received prior chemotherapy had the highest response rate, at 75%.

CONCLUSION

The recommended phase II doses for this regimen are cisplatin 75 mg/m2 i.v. day 1, etoposide 50 mg/m2 i.v. day 1 and orally days 2-5, and gemcitabine 800 mg/m2 i.v. days 1 and 8. Future trials should further examine the optimal relative doses and schedule of gemcitabine and etoposide.

Enhancement of radiation-induced regrowth delay by gemcitabine in a human tumor xenograft model

Gemcitabine, a cytidine nucleoside analogue, has schedule-dependent antitumor activity in vitro and in vivo. Gemcitabine also has dose- and time-dependent radiosensitization properties in vitro. Thus it may have therapeutic application in combination with radiation. The aims of this study were to investigate whether gemcitabine could enhance radiation-induced tumor regrowth delay in a human squamous carcinoma (FaDu) xenograft in nude mice and to examine the effect of gemcitabine on radiation-induced apoptosis in in vivo tumors. Radiation was given locally to the tumors twice daily in 2 Gy fractions over 2 weeks for 5 days/week. Significant regrowth delay enhancement was observed which was dependent on gemcitabine schedule. Effective schedules using maximum tolerated gemcitabine doses were twice weekly and once weekly, but not daily. Significant toxicity occurred with radiation plus twice weekly gemcitabine, but enhancement was seen using gemcitabine doses well below the maximum tolerated dose. Both gemcitabine and radiation led to apoptotic cell death, but this was not increased when both treatments were combined. These results indicate that gemcitabine may be of therapeutic value as a radiation enhancer in the treatment of human cancers. Preliminary studies suggest that increased apoptotic cell death is not a mechanism leading to this enhancement.

Gemcitabine. A review of its pharmacology and clinical potential in non-small cell lung cancer and pancreatic cancer

Gemcitabine [2'-deoxy-2',2'-difluorocytidine monohydrochloride (beta isomer); dFdC] is a novel deoxycytidine analogue which was originally investigated for its antiviral effects but has since been developed as an anticancer therapy. Gemcitabine monotherapy produced an objective tumour response in 18 to 26% of patients with advanced non-small cell lung cancer (NSCLC) and appears to have similar efficacy to cisplatin plus etoposide. Objective response rates ranging from 26 to 54% were recorded when gemcitabine was combined with cisplatin, and 1-year survival duration after such treatment ranged from 35 to 61%. Improvements in a range of NSCLC disease symptoms and/or in general performance status occurred in many patients who received gemcitabine, with or without cisplatin, in 3 clinical trials. Gemcitabine appears to be cost effective compared with best supportive care for NSCLC. In addition, direct costs associated with administration of gemcitabine monotherapy may be lower than those for some other NSCLC chemotherapy options, according to retrospective cost-minimisation analyses. The combination of gemcitabine plus cisplatin was associated with a lower cost per tumour response than cisplatin plus etoposide or cisplatin plus vinorelbine, according to a retrospective cost-effectiveness analysis. In a single comparative study in patients with advanced pancreatic cancer, gemcitabine was more effective than fluorouracil with respect to survival duration and general clinical status. It also showed modest antitumour and palliative efficacy in patients refractory to fluorouracil. Gemcitabine appears to be well tolerated, although further comparisons with other chemotherapy regimens are required. The available data indicate that gemcitabine monotherapy is better tolerated than cisplatin plus etoposide in patients with NSCLC. Data from noncomparative studies suggest that the combination of gemcitabine and cisplatin has an acceptable tolerabilty profile. In a single trial in patients with pancreatic cancer, fluorouracil was better tolerated than gemcitabine; however, gemcitabine was generally well tolerated overall in this study. Thus, gemcitabine (with or without cisplatin) may prove attractive to patients with advanced NSCLC, given their limited life expectancy and the toxicity associated with many other chemotherapy regimens. More detailed characterisation of its risk-benefit profile compared with those of current and developing regimens for NSCLC should be possible once results from several ongoing studies are available. Gemcitabine is a valuable new chemotherapy option for patients with advanced pancreatic cancer, a disease considered incurable at present. Its apparent survival and palliative benefits over fluorouracil require confirmation, but are encouraging, as the need to improve both the duration and quality of survival in these patients is well recognised.

Phase I study of gemcitabine using a once every 2 weeks schedule

Gemcitabine (2',2'-difluorodeoxycytidine) is a novel nucleoside analogue. As part of a series of studies to determine the maximum tolerated dose (MTD) of gemcitabine and the most appropriate schedule, a two-centre phase I study of gemcitabine was undertaken in patients with advanced refractory solid tumours using a once every 2 weeks schedule. Fifty-two patients were entered into the study at 14 different dose levels (40-5700 mg m-2). Weekly evaluations for toxicity were performed and the MTD for this once every 2 weeks schedule was 5700 mg m-2. The dose-limiting toxicity was myelosuppression, with neutropenia being most significant. Other toxicities were nausea, vomiting, fever and asthenia. One minor response was seen in a heavily pretreated breast cancer patient treated at 1200 mg m-2. Preclinical studies suggest that the efficacy of gemcitabine is more schedule than dose related, and it is concluded that this is not the most appropriate dosing schedule for gemcitabine. However, this study demonstrates the safety profile of gemcitabine, as doses over fourfold greater than that recommended for the weekly schedule of 1000 mg m-2 could be tolerated.

Evaluation of the optimal duration of chemotherapy in phase II trials for inoperable non-small-cell lung cancer (NSCLC)

PURPOSE

To determine the optimal duration of chemotherapy in phase II trials for patients with non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

The time from start of treatment until achievement of response according to WHO criteria was determined retrospectively in 8 phase II trials.

RESULTS

Response to chemotherapy consisting of 4 complete and 39 partial remissions was registered in 43 of 333 patients. The median time from treatment start to response was 54 days. On day 84 on-study, 35 of the responding patients (81%) had achieved the response. Forty-three responses (98%) had occurred by day 168 and only one patient (2%) accomplished a response after 168 days of treatment. The responses had a median duration of 151 days (range 28-1559 days).

CONCLUSIONS

The data indicate that patients with NSCLC included in phase II trials who have not yet achieved a response to chemotherapy after 168 days on study have a low likelihood (2%) of a subsequent response. Hence, treatment cessation at this point should be considered for non-responding patients. Continuation of treatment from day 84 to day 168 resulted in response in only 7 patients out of the total of 43 responses noted (16%). Thus, the toxic effects of the chemotherapy in addition to the inconvenience of hospital visits renders it questionable whether it is worthwhile to continue treatment in patients with inoperable non-small-cell lung cancer beyond day 84 in the absence of response.