Afatinib beyond progression in patients with non-small-cell lung cancer following chemotherapy, erlotinib/gefitinib and afatinib: phase III randomized LUX-Lung 5 trial

BACKGROUND

Afatinib has demonstrated clinical benefit in patients with non-small-cell lung cancer progressing after treatment with erlotinib/gefitinib. This phase III trial prospectively assessed whether continued irreversible ErbB-family blockade with afatinib plus paclitaxel has superior outcomes versus switching to chemotherapy alone in patients acquiring resistance to erlotinib/gefitinib and afatinib monotherapy.

PATIENTS AND METHODS

Patients with relapsed/refractory disease following ≥1 line of chemotherapy, and whose tumors had progressed following initial disease control (≥12 weeks) with erlotinib/gefitinib and thereafter afatinib (50 mg/day), were randomized 2:1 to receive afatinib plus paclitaxel (40 mg/day; 80 mg/m(2)/week) or investigator's choice of single-agent chemotherapy. The primary end point was progression-free survival (PFS). Other end points included objective response rate (ORR), overall survival (OS), safety and patient-reported outcomes.

RESULTS

Two hundred and two patients with progressive disease following clinical benefit from afatinib were randomized to afatinib plus paclitaxel (n = 134) or single-agent chemotherapy (n = 68). PFS (median 5.6 versus 2.8 months, hazard ratio 0.60, P = 0.003) and ORR (32.1% versus 13.2%, P = 0.005) significantly improved with afatinib plus paclitaxel. There was no difference in OS. Global health status/quality of life was maintained with afatinib plus paclitaxel over the entire treatment period. The median treatment duration was 133 and 51 days with afatinib plus paclitaxel and single-agent chemotherapy, respectively; 48.5% of patients receiving afatinib plus paclitaxel and 30.0% of patients receiving single-agent chemotherapy experienced drug-related grade 3/4 adverse events. Treatment-related adverse events were consistent with those previously reported with each agent.

CONCLUSION

Afatinib plus paclitaxel improved PFS and ORR compared with single-agent chemotherapy in patients who acquired resistance to erlotinib/gefitinib and progressed on afatinib after initial benefit. LUX-Lung 5 is the first prospective trial to demonstrate the benefit of continued ErbB targeting post-progression, versus switching to single-agent chemotherapy.

TRIAL REGISTRATION NUMBER

NCT01085136 (clinicaltrials.gov).

PARAMOUNT: Phase III study of maintenance pemetrexed (pem) plus best supportive care (BSC) versus placebo plus BSC immediately following induction treatment with pem plus cisplatin for advanced nonsquamous non-small cell lung cancer (NSCLC)

CRA7510

Background: The PARAMOUNT trial investigated whether pem continuation maintenance therapy improves progression-free survival (PFS) after pem-cisplatin induction therapy in patients (pts) with advanced nonsquamous NSCLC. Methods: In this double-blind, placebo-controlled trial, 939 pts participated in the induction phase, specified as four cycles of induction pem (500 mg/m2) and cisplatin (75 mg/m2) on day 1 of a 21-day cycle. Pts who had not progressed during pem-cisplatin induction and had an Eastern Cooperative Oncology Group performance status (PS) of 0/1 (n=539; 57.4%) were randomized (2:1, stratified for disease stage, PS, and induction response) to maintenance pem (500 mg/m2 on day 1 of a 21-day cycle) plus BSC (n=359) or placebo plus BSC (n=180) until disease progression. All pts received vitamin B12, folic acid, and dexamethasone. The primary endpoint was PFS (target: HR=0.65, two-sided alpha=0.05; 90% power with minimum of 238 events). Results: Pt characteristics were balanced between arms: median age=61 years; 58% male; 95% Caucasian; 32% PS 0; 91% stage IV; 87% adenocarcinoma; and 45% induction complete/partial response. Pem continuation maintenance resulted in a 36% reduction in the risk of progression (HR=0.64, 95% CI: 0.51-0.81; P=0.00025). The median independently reviewed PFS (472 pts, 297 events), measured from randomization, was 3.9 months (95% CI: 3.0-4.2) on the pem arm, and 2.6 months (95% CI: 2.2-2.9) on the placebo arm. The disease control rate (% pts with response/stable disease) was 71.8% on the pem arm, and 59.6% on the placebo arm (P=0.009). The drug-related serious adverse event (AE) rate was 8.9% on the pem arm, and 9.2% of pts had grade 3/4 laboratory Common Toxicity Criteria AEs. On the placebo arm, the rates were 2.8% and 0.6%, respectively. Discontinuations due to AEs were 5.3% on the pem arm, 3.3% on the placebo arm. Conclusions: PARAMOUNT met its primary endpoint and showed that pem continuation maintenance following pem-cisplatin induction is an effective and well tolerated treatment for pts with advanced nonsquamous NSCLC.