Recent advances in lung cancer: summary of presentations from the 45th annual meeting of the American Society of Clinical Oncology (2009)

Over the past decade, gradual progress has been made in improving the outcomes of patients with lung cancer. This review summarizes the findings from selected studies presented at the recently concluded 45th annual meeting of the American Society of Clinical Oncology. This report will focus only on findings that are of immediate relevance to clinical practice. The topics discussed here range from the long-term safety of adjuvant chemotherapy and a new systemic chemotherapy regimen for locally advanced non-small cell lung cancer to the emerging issue of maintenance chemotherapy and the use of biomarkers in the treatment of patients with metastatic non-small cell lung cancer.

Treatment rationale and study design for a phase III, double-blind, placebo-controlled study of maintenance pemetrexed plus best supportive care versus best supportive care immediately following induction treatment with pemetrexed plus cisplatin for advanced nonsquamous non-small cell lung cancer

BACKGROUND

To improve the efficacy of first-line therapy for advanced non-small cell lung cancer (NSCLC), additional maintenance chemotherapy may be given after initial induction chemotherapy in patients who did not progress during the initial treatment, rather than waiting for disease progression to administer second-line treatment. Maintenance therapy may consist of an agent that either was or was not present in the induction regimen. The antifolate pemetrexed is efficacious in combination with cisplatin for first-line treatment of advanced NSCLC and has shown efficacy as a maintenance agent in studies in which it was not included in the induction regimen. We designed a phase III study to determine if pemetrexed maintenance therapy improves progression-free survival (PFS) and overall survival (OS) after cisplatin/pemetrexed induction therapy in patients with advanced nonsquamous NSCLC. Furthermore, since evidence suggests expression levels of thymidylate synthase, the primary target of pemetrexed, may be associated with responsiveness to pemetrexed, translational research will address whether thymidylate synthase expression correlates with efficacy outcomes of pemetrexed.

METHODS/DESIGN

Approximately 900 patients will receive four cycles of induction chemotherapy consisting of pemetrexed (500 mg/m2) and cisplatin (75 mg/m2) on day 1 of a 21-day cycle. Patients with an Eastern Cooperative Oncology Group performance status of 0 or 1 who have not progressed during induction therapy will randomly receive (in a 2:1 ratio) one of two double-blind maintenance regimens: pemetrexed (500 mg/m2 on day 1 of a 21-day cycle) plus best supportive care (BSC) or placebo plus BSC. The primary objective is to compare PFS between treatment arms. Secondary objectives include a fully powered analysis of OS, objective tumor response rate, patient-reported outcomes, resource utilization, and toxicity. Tumor specimens for translational research will be obtained from consenting patients before induction treatment, with a second biopsy performed in eligible patients following the induction phase.

DISCUSSION

Although using a drug as maintenance therapy that was not used in the induction regimen exposes patients to an agent with a different mechanism of action, evidence suggests that continued use of an agent present in the induction regimen as maintenance therapy enables the identification of patients most likely to benefit from maintenance treatment.

TRIAL REGISTRATION

TRIAL REGISTRY

Clinicaltrials.gov

REGISTRATION NUMBER

NCT00789373 TRIAL ABBREVIATION: H3E-EW-S124.

Maintenance pemetrexed plus best supportive care versus placebo plus best supportive care for non-small-cell lung cancer: a randomised, double-blind, phase 3 study

BACKGROUND

Several studies have shown the efficacy, tolerability, and ease of administration of pemetrexed-an antifolate antineoplastic agent-in patients with advanced non-small-cell lung cancer. We assessed pemetrexed as maintenance therapy in patients with this disease.

METHODS

This randomised double-blind study was undertaken in 83 centres in 20 countries. 663 patients with stage IIIB or IV disease who had not progressed on four cycles of platinum-based chemotherapy were randomly assigned (2:1 ratio) to receive pemetrexed (500 mg/m(2), day 1) plus best supportive care (n=441) or placebo plus best supportive care (n=222) in 21-day cycles until disease progression. Treatment was randomised with the Simon and Pocock minimisation method. Patients and investigators were masked to treatment. All patients received vitamin B(12), folic acid, and dexamethasone. The primary endpoint of progression-free survival and the secondary endpoint of overall survival were analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00102804.

FINDINGS

All randomly assigned participants were analysed. Pemetrexed significantly improved progression-free survival (4.3 months [95% CI 4.1-4.7] vs 2.6 months [1.7-2.8]; hazard ratio [HR] 0.50, 95% CI 0.42-0.61, p<0.0001) and overall survival (13.4 months [11.9-15.9] vs 10.6 months [8.7-12.0]; HR 0.79, 0.65-0.95, p=0.012) compared with placebo. Treatment discontinuations due to drug-related toxic effects were higher in the pemetrexed group than in the placebo group (21 [5%] vs three [1%]). Drug-related grade three or higher toxic effects were higher with pemetrexed than with placebo (70 [16%] vs nine [4%]; p<0.0001), specifically fatigue (22 [5%] vs one [1%], p=0.001) and neutropenia (13 [3%] vs 0, p=0.006). No pemetrexed-related deaths occurred. Relatively fewer patients in the pemetrexed group than in the placebo group received systemic post-discontinuation therapy (227 [51%] vs 149 [67%]; p=0.0001).

INTERPRETATION

Maintenance therapy with pemetrexed is well tolerated and offers improved progression-free and overall survival compared with placebo in patients with advanced non-small-cell lung cancer.

FUNDING

Eli Lilly.

A randomized phase II trial assessing in advanced non-small cell lung cancer patients with stable disease after two courses of cisplatin-gemcitabine an early modification of chemotherapy doublet with paclitaxel-gemcitabine versus continuation of cisplatin-gemcitabine chemotherapy (GFPC 03-01 Study)

BACKGROUND

There is no consensus on the optimal treatment for patients with advanced non-small cell lung cancer and stable disease after cisplatin-based chemotherapy. The objective of the trial was to evaluate a switch to a different dual-agent chemotherapy.

METHODS

Patients with stage IV non-small cell lung cancer and stable disease after two cycles of cisplatin (P) and gemcitabine (G) (P day1 (d(1)): 75 mg/m(2), G: 1250 mg/m(2) d(1) and d(8) every 3 weeks) were randomized to receive either two further cycles of PG (arm A) or paclitaxel (100 mg/m(2) d(1), d(8), d(15)) plus gemcitabine (1250 mg/m(2) d(1) and d(8), every 4 weeks) (arm B).

RESULTS

Two-hundred-twenty-eight patients were enrolled between October 2003 and August 2006. After two cycles of PG, 98 patients (43%) had stable disease; 87 were randomized: 45 to arm A and 42 to arm B. The objective response rates were 15.6% (6.5-29.4) and 21.4% (10.3-36.8) in arms A and B. Overall survival after randomization was 9.6 months (7.0-13.8) in arm A and 9.3 months (7.4-13.3) in arm B. Adverse events were similar in the two arms for hematological and non hematological toxicities.

CONCLUSIONS

Sequential first-line chemotherapy in these patients is feasible with no difference in response rates. These results do not warrant a phase III trial.

From the podium to the patient: bringing the 2008 ASCO meeting to the clinic

Around 4,800 abstracts on preclinical and clinical research in different oncology areas were presented and discussed by oncology clinicians and scientists at the 44th American Society of Clinical Oncology meeting, the largest international forum in the field. As expected, the meeting provided valuable insights into future developments as well as enlightening clinicians regarding current controversies. This manuscript is an opinion-based review of the studies presented at the meeting, focusing on findings from randomized phase III trials and translational researches that, in the authors' opinion, are most likely to modify clinical practice or help scientists in designing future translational and clinical studies.