Phase II selection design trial of concurrent chemotherapy and cetuximab versus chemotherapy followed by cetuximab in advanced-stage non-small-cell lung cancer: Southwest Oncology Group study S0342

Abstract

Purpose: Randomized clinical trials failed to show a survival benefit for epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors plus concurrent chemotherapy in patients with metastatic non-small-cell lung cancer (NSCLC), with preclinical data suggesting potential negative interactions. In contrast, pilot trials of the EGFR-targeted antibody, cetuximab, plus chemotherapy suggested enhanced antitumor activity. This randomized phase II trial was designed to select a cetuximab plus chemotherapy regimen for phase III evaluation.

Patients and methods: Treatment-naive patients with advanced-stage NSCLC were randomly assigned to receive paclitaxel (225 mg/m(2)) and carboplatin (area under the curve, 6) every 3 weeks plus concurrent cetuximab (400 mg/m(2) loading dose followed by 250 mg/m(2) weekly) for four cycles followed by maintenance cetuximab or sequential paclitaxel-carboplatin for four cycles followed by cetuximab.

Results: Of 242 patients enrolled, 224 were eligible and assessable for response (106 and 118 patients in the concurrent and sequential arms, respectively). With a median follow-up time of 32 months, the median overall survival was 10.9 months (95% CI, 9.2 to 13.0 months) for patients receiving concurrent therapy and 10.7 months (95% CI, 8.5 to 12.8 months) for patients receiving sequential therapy (P = .57); 1-year survival rates were 45% (95% CI, 36% to 54%) and 44% (95% CI, 35% to 53%), respectively. Response rates and progression-free survival times were similar in both arms, as was grade 3 rash, whereas sensory neuropathy was higher in the concurrent arm (15% v 5% in the sequential arm; P = .036).

Conclusion: Although both regimens met the efficacy criterion for continued evaluation, the concurrent regimen of paclitaxel/carboplatin plus cetuximab was chosen.

Fig 1.

CONSORT diagram. wk, week; q 21 d, every 21 days; AUC, area under the curve; ITT, intent to treat; AE, adverse event; Tx, treatment.

Fig 2.

Kaplan-Meier curves for overall survival in patients with advanced non–small-cell lung cancer (NSCLC) treated (A) with concurrent chemotherapy plus cetuximab and (B) sequentially with chemotherapy followed by cetuximab.

Fig 3.

Progression-free survival in patients with advanced non–small-cell lung cancer (NSCLC) treated (A) with concurrent chemotherapy plus cetuximab and (B) sequentially with chemotherapy followed by cetuximab.

Fig 4.

Progression-free survival by wild-type versus mutant KRAS (A) in tissue alone and (B) in plasma or tissue and overall survival by wild-type versus mutant KRAS (C) in tissue alone and (D) in plasma or tissue in patients with advanced non–small-cell lung cancer treated with concurrent chemotherapy plus cetuximab versus chemotherapy followed by cetuximab.