Predictive biomarkers for response to EGFR-directed monoclonal antibodies for advanced squamous cell lung cancer.

Background: Upregulated expression and aberrant activation of the epidermal growth-factor receptor (EGFR) are found in lung cancer, making EGFR a relevant target for non-small-cell lung cancer (NSCLC). Treatment with anti-EGFR monoclonal antibodies (mAbs) is associated with modest improvement in overall survival in patients with squamous cell lung cancer (SqCLC) who have a significant unmet need for effective treatment options. While there is evidence that using EGFR gene copy number, EGFR mutation, and EGFR protein expression as biomarkers can help select patients who respond to treatment, it is important to consider biomarkers for response in patients treated with combination therapies that include EGFR mAbs. Design: Randomized trials of EGFR-directed mAbs cetuximab and necitumumab in combination with chemotherapy, immunotherapy, or antiangiogenic therapy in patients with advanced NSCLC, including SqCLC, were searched in the literature. Results of associations of potential biomarkers and outcomes were summarized. Results: Data from phase III clinical trials indicate that patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein (H-score of ≥200) and/or gene copy numbers of EGFR (e.g. ≥40% cells with ≥4 EGFR copies as detected by fluorescence in situ hybridization; gene amplification in ≥10% of analyzed cells) derive greater therapeutic benefits from EGFR-directed mAbs. Biomarker data are limited for EGFR mAbs used in combination with immunotherapy and are absent when used in combination with antiangiogenic agents. Conclusions: Therapy with EGFR-directed mAbs in combination with chemotherapy is associated with greater clinical benefits in patients with NSCLC, including SqCLC, whose tumors express high levels of EGFR protein and/or have increased EGFR gene copy number. These data support validating the role of these as biomarkers to identify those patients who derive the greatest clinical benefit from EGFR mAb therapy. However, data on biomarkers for EGFR-directed mAbs combined with immunotherapy or antiangiogenic agents remain limited.

Identifying the target NSCLC patient for maintenance therapy: an analysis from a placebo-controlled, phase III trial of maintenance pemetrexed (H3E-MC-JMEN).

BACKGROUND: This was a post hoc analysis of patients with non-squamous histology from a phase III maintenance pemetrexed study in advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The six symptom items' [average symptom burden index (ASBI)] mean at baseline was calculated using the lung cancer symptom scale (LCSS). Low and high symptom burden (LSB, ASBI < 25; HSB, ASBI ≥ 25) and performance status (PS: 0, 1) subgroups were analyzed for treatment effect on progression-free survival (PFS) and overall survival (OS) using the Cox proportional hazard models adjusted for demographic/clinical factors. RESULTS: Significantly longer PFS and OS for pemetrexed versus placebo occurred in LSB patients [PFS: median 5.1 versus 2.4 months, hazard ratio (HR) 0.49, P < 0.0001; OS: median 17.5 versus 11.0 months, HR 0.63, P = 0.0012] and PS 0 patients (PFS: median 5.5 versus 1.7 months, HR 0.36, P < 0.0001; OS: median 17.7 versus 10.3 months, HR 0.54, P = 0.0019). Significantly longer PFS, but not OS, occurred in HSB patients (median 3.7 versus 2.8 months, HR 0.50, P = 0.0033) and PS 1 patients (median 4.4 versus 2.8 months, HR 0.60, P = 0.0002). CONCLUSIONS: ASBI and PS are associated with survival for non-squamous NSCLC patients, suggesting that maintenance pemetrexed is useful for LSB or PS 0 patients following induction.

Phase III trial of gemcitabine plus docetaxel versus capecitabine plus docetaxel with planned crossover to the alternate single agent in metastatic breast cancer.

BACKGROUND: Safety and efficacy of gemcitabine plus docetaxel (GD) and capecitabine plus docetaxel (CD) were compared in patients with metastatic breast cancer, where the alternate crossover monotherapy (GD→C or CD→G) was predetermined. PATIENTS AND METHODS: Patients were randomly assigned to 3-week cycles of either gemcitabine 1000 mg/m(2) on days 1 and 8 plus docetaxel 75 mg/m(2) on day 1 or capecitabine 1000 mg/m(2) twice daily on days 1-14 plus docetaxel 75 mg/m(2) day 1. Upon progression, patients received crossover monotherapy. Primary end point was time to progression (TtP). Secondary end points evaluated overall response rate (ORR), overall survival (OS), and adverse events (AEs). RESULTS: Despite over-accrual of 475 patients, the trial matured with only 324 of 385 planned TtP events due to patient discontinuations. Human epidermal growth factor receptor 2 status was not captured in this study. More CD patients (28%) discontinued due to AEs than GD patients (18.0%, P = 0.009). TtP [hazard ratio (HR) = 1.101, 95% confidence interval (CI) 0.885-1.370, P = 0.387] and OS (HR = 1.031, 95% CI 0.830-1.280, P = 0.785) were not significantly different comparing GD and CD. ORR was not statistically different (P = 0.239) comparing GD (72 of 207, 34.8%) and CD (78 of 191, 40.8%). TtP, OS, and ORR were not significantly different comparing crossover groups. GD caused greater fatigue, hepatotoxicity, neutropenia, and thrombocytopenia but not febrile neutropenia; CD caused more hand-foot syndrome, gastrointestinal toxicity, and mucositis. CONCLUSIONS: GD and CD produced similar efficacy and toxicity profiles consistent with prior clinical experience.

A randomized, phase III multicenter trial of gemcitabine in combination with carboplatin or paclitaxel versus paclitaxel plus carboplatin in patients with advanced or metastatic non-small-cell lung cancer.

BACKGROUND: Paclitaxel-carboplatin is used as the standard regimen for patients with advanced or metastatic non-small-cell lung cancer (NSCLC). This trial was designed to compare gemcitabine + carboplatin or gemcitabine + paclitaxel to the standard regimen. PATIENTS AND METHODS: A total of 1135 chemonaive patients with stage IIIB or IV NSCLC were randomly allocated to receive gemcitabine 1000 mg/m(2) on days 1 and 8 plus carboplatin area under the concentration-time curve (AUC) 5.5 on day 1 (GC), gemcitabine 1000 mg/m(2) on days 1 and 8 plus paclitaxel 200 mg/m(2) on day 1 (GP), or paclitaxel 225 mg/m(2) plus carboplatin AUC 6.0 on day 1 (PC). Stratification was based on disease stage, baseline weight loss, and presence or absence of brain metastases. Cycles were repeated every 21 days for up to six cycles or disease progression. RESULTS: Median survival (months) with GC was 7.9 compared with 8.5 for GP and 8.7 for PC. Response rates (RRs) were as follows: GC, 25.3%; GP, 32.1%; and PC, 29.8%. The GC arm was associated with a greater incidence of grade 3 or 4 hematologic events but a lower rate of neurotoxicity and alopecia when compared with GP and PC. CONCLUSIONS: Non-platinum and non-paclitaxel gemcitabine-containing doublets demonstrate similar overall survival and RR compared with the standard PC regimen. However, the treatment arms had distinct toxicity profiles.

Gemcitabine and pemetrexed administered in rapid sequence as front-line chemotherapy for advanced non-small-cell lung cancer: a phase II clinical trial.

BACKGROUND: Previous studies of the gemcitabine-pemetrexed combination in patients with late-stage non-small-cell lung cancer (NSCLC) utilized a 90-min delay between gemcitabine and pemetrexed administration. This phase II study evaluated activity when these agents were administered in rapid succession. MATERIALS AND METHODS: Chemonaive patients with late-stage NSCLC received gemcitabine 1250 mg/m(2) on days 1 and 8, with pemetrexed 500 mg/m(2) immediately following day 8 gemcitabine every 21 days for six cycles, folic acid, B(12), and steroid prophylaxis. RESULTS: Fifty-four enrolled patients (53 treated) completed a median of four cycles. Median dose intensity was 84% (gemcitabine) and 83% (pemetrexed); 68% of patients required dose adjustments. Response was as follows: complete response, 0; partial response, 7 (13%); stable disease, 29 (54%); progressive disease, 9 (17%); and unknown/unavailable, 9 (17%). Median progression-free and overall survival was 4.6 and 12.4 months, respectively. Common grade 3 or 4 toxic effects were as follows: neutropenia (40%); fatigue and dyspnea (21% each); pneumonia (17%); febrile neutropenia and thrombocytopenia (11% each); and anemia (6%). CONCLUSIONS: The gemcitabine-pemetrexed combination is minimally active in late-stage NSCLC, with a high incidence of grade 3 or 4 toxic effects requiring frequent dose adjustments. A gemcitabine dose <1250 mg/m(2) warrants consideration for future trials exploring this doublet. Administering day 8 pemetrexed immediately after gemcitabine does not appear to negatively impact therapeutic index.

Evaluation of carboplatin pharmacokinetics in the absence and presence of paclitaxel.

In a clinical trial of paclitaxel (Taxol) and carboplatin in combination, the severity of thrombocytopenia was less than would be expected with an equivalent dose of carboplatin alone. To determine whether a pharmacokinetic interaction was responsible for this observation, the effect of pretreatment with Taxol on the pharmacokinetics of carboplatin was examined in 11 patients. Each patient was randomized to one of two treatment groups that determined the order of drug treatments. The treatments were carboplatin as a 30-min infusion alone or immediately following 175 mg/m2 Taxol administered as a 3-h i.v. infusion. The treatments were separated by 1 week. The carboplatin dose was chosen to produce a target area under the concentration-time curve (AUC) of 3.75 mg-min/ml according to a previously published formula (A. H. Calvert et al., J. Clin Oncol., 7: 1748-1756, 1989). The mean administered dose of carboplatin was 338 mg. Serial blood samples were collected over 24 h and analyzed for total and free platinum, and, in some patients, Taxol. The pharmacokinetics of carboplatin (i.e., total clearance and volume of distribution at steady state), was not significantly affected by pretreatment with Taxol. Total clearances of carboplatin were 67.2 +/- 28.8 ml/min and 64.6 +/- 27.9 ml/min in the absence and presence of Taxol, respectively (P = 0.56). The AUC of free carboplatin (3.45 mg-min/ml) obtained in the absence of Taxol was not significantly different from that measured in the presence of Taxol (3.27 mg-min/ml). The AUC of carboplatin in both the absence and presence of Taxol agreed with the projected target AUC of 3.75 mg-min/ml. In conclusion, the application of an individualized dosing strategy is valid for the calculation of the carboplatin dose in this combination. The pharmacokinetics of carboplatin is not altered by pretreatment with Taxol at a standard dose, and a pharmacokinetic interaction is not responsible for the altered toxicity of the combination.

Phase I study of paclitaxel and estramustine: preliminary activity in hormone-refractory prostate cancer.

Estramustine phosphate is a unique antimitotic agent that binds to tubulin and microtubule-associated proteins. Preclinically, estramustine combined with other microtubule inhibitors, like vinblastine or paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), produced additive or greater antimitotic and cytotoxic effects. Clinically, the estramustine/vinblastine combination has significant activity in hormone-refractory prostate cancer. We have begun a phase I study of paclitaxel by 96-hour continuous infusion every 3 weeks combined with daily oral estramustine (600 mg/m2). Eighteen patients with refractory solid tumors have received paclitaxel doses ranging from 80 to 140 mg/m2. Grade 3 or 4 granulocytopenia occurred in one of seven and two of four patients treated at the 120- and 140-mg/m2 dose levels, respectively. The latter two patients experienced grade 3 mucositis and had mean plasma paclitaxel levels exceeding 0.1 mumol/L. Other toxicities, principally nausea and hepatic function abnormalities, have been mild. The apparent steady-state concentrations of paclitaxel 100 and 120 mg/m2 administered with estramustine are similar to those reported for single-agent paclitaxel administered as a 96-hour infusion at doses of 100 and 120 mg/m2. In contrast, at the 140 mg/m2 dose level, paclitaxel concentrations increased throughout the infusion, and steady state was not reached in three of the four patients treated. Objective responses have been observed in two of three patients with adenocarcinoma of the esophagus and in two patients with hormone-resistant prostate cancer and measurable soft tissue metastases. Two additional patients with prostate cancer have been treated with the estramustine/paclitaxel combination, one achieving a major response and the other stable disease. The recommended phase II dose for 96-hour infusional paclitaxel with daily oral estramustine is at least 120 mg/m2. Studies to determine the effect of estramustine on paclitaxel pharmacokinetics are continuing. The antitumor activity observed merits phase II studies of this combination in hormone-resistant prostate cancer and other malignancies.

Paclitaxel and docetaxel in prostate cancer.

Although their ultimate value in prostate cancer therapy remains to be defined in randomized trials, docetaxel and paclitaxel are active agents in HRPC. Combination therapies using either of these taxanes plus oral EMP show reproducible antitumor activity that appears to be greater and more durable than that of single-agent treatment. Although the optimal combination and schedule have not been determined, weekly paclitaxel and EMP and docetaxel given every 3 weeks or by weekly infusion with EMP are useful treatment options for patients with progressive HRPC. The gastrointestinal toxicity of EMP has been reduced by intermittent rather than continuous administration, and other toxicities may be reduced further by use of intravenous EMP. Although there has been progress, the median time to progression of 5 to 6 months for current taxane-based therapies suggests that they will not have major impact on overall survival for patients with HRPC. Greater benefit may be possible earlier in the course of prostate cancer, and the activity of the taxane-EMP combinations is sufficient to justify clinical trials of adjuvant or neoadjuvant chemotherapy for selected groups of patients with locally advanced and poor-prognosis tumors. Armed with many new molecularly targeted agents that may interact favorably with taxanes, it should be possible to build on current antimicrotubule regimens to improve activity in HRPC. Taxane-EMP combinations provide a platform on which to test additional agents that may enhance the apoptotic response or circumvent cellular stress adaptations that confer drug resistance. Further elucidation of signaling pathways that regulate microtubule dynamics and programmed cell death after exposure to microtubule inhibitors would provide a more rational guide for integrating specific inhibitors of signal transduction with current taxane-based therapies. Pharmacokinetic and pharmacodynamic studies will play a key role in the development of future taxane-based therapies for prostate cancer.

Phase II evaluation of menogaril in advanced prostate cancer: Eastern Cooperative Oncology Group EST P-A885.

Menogaril is a semisynthetic anthracycline that is less cardiotoxic than doxorubicin in a preclinical model. We conducted a phase II trial to determine the activity of menogaril in hormone-refractory prostate cancer. Between October 1985 and November 1987, 32 eligible patients were enrolled and were divided into good- and poor-risk categories, the latter being defined by prior radiotherapy to less than one third of the marrow-containing skeleton. Good-risk patients received a starting dose of 200 mg/m2 by 60-minute IV infusion, whereas the poor-risk patients received 160 mg/m2. Treatment was repeated every 3 weeks until disease progression. Menogaril caused leukopenia in 90% of patients, of whom 47% had grade III or IV toxicity. Thrombocytopenia was uncommon and mild, with only three patients (9%) experiencing grade II toxicity. Nonhematologic toxicity included mucositis (9%), and mild weight loss in 33% of patients. Nine patients (28%) had stable disease of 3 or more months' duration. There were no objective partial or complete responses. The median time to progression for the entire group was 10 weeks, and the median survival time for all patients was 24 weeks. Because of appreciable toxicity and limited antitumor activity, further study of menogaril cannot be recommended in hormone-refractory prostate cancer.

Recurrent cervical cancer treated with cisplatin and methotrexate.

A combination of cisplatin (80 mg/m2) and methotrexate (200 mg bolus and 400 mg as a 12-hour infusion) was given to 40 patients who developed local recurrence of cervical cancer after radiotherapy. A maximum of six courses was given at monthly intervals. Twenty-five of the forty (63%) evaluable patients responded, of which 4 (10%) responded completely. A symptomatic response, with reduction of pain, leg oedema, vaginal discharge and breathlessness was seen in 27 (68%) of patients. The median survival of all patients was 11 months. Toxicity was moderate; WHO grade 1 or greater was observed in 83% for nausea and vomiting, 67% for myelosuppression and 47% for mucositis. This combination chemotherapy is active in the treatment of recurrent cervical cancer and a modification of this regimen is currently being assessed as neo-adjuvant therapy in patients with Stage IIB-IVA cervical cancer.

Randomized phase II trial of gemcitabine plus weekly versus three-weekly paclitaxel in previously untreated advanced non-small-cell lung cancer.

INTRODUCTION: Gemcitabine and paclitaxel (Taxol) each provides an efficacious non-platinum option for the treatment of advanced non-small-cell lung cancer (NSCLC), but the optimal dosage and schedule of the two agents used in combination are not well defined. METHODS: Previously untreated patients with advanced NSCLC were randomized to receive gemcitabine-paclitaxel on a traditional three-weekly schedule (Arm A) or a novel weekly schedule (Arm B) as follows-Arm A (three-weekly): gemcitabine 1000 mg/m2 infused>30 min on days 1 and 8 and paclitaxel 200 mg/m2 infused>3 h on day 1 of a 21-day cycle or Arm B (weekly): gemcitabine 1000 mg/m2 infused>30 min and paclitaxel 100 mg/m2 infused>1 h, both administered on days 1 and 8 of a 21-day cycle. RESULTS: One hundred patients received at least one dose of treatment. The weekly schedule, Arm B, was more efficacious and less hematologically toxic than Arm A. Confirmed complete and partial response rates were 28.2% and 26.8%, respectively. Median survival was 10.3 months on Arm B and 7.9 months on Arm A (log-rank P=0.10); 1- and 2-year survival rates also favor Arm B: 42.0% versus 34.0% and 18.0% versus 6.0%. Progression-free survival was 5.8 versus 4.8 months, again favoring Arm B (log-rank P=0.06). There was a two-fold lower frequency of grade 3/4 hematologic events with Arm B as follows: neutropenia (16% versus 30%), thrombocytopenia (4% versus 8%), and anemia (2% versus 6%). One patient (2%) in each treatment group developed febrile neutropenia. CONCLUSION: In this trial, both schedules were efficacious and tolerable, although the weekly schedule resulted in improved survival and lower hematologic toxicity compared with a three-weekly schedule. The weekly schedule of gemcitabine-paclitaxel indicates an improved therapeutic index.