A phase II study of concurrent pemetrexed/cisplatin/radiation (RT) for unresectable stage IIIA/b non-small cell lung cancer (NSCLC).

7087 Background: Concurrent chemoRT is standard of care for most patients with unresectable stage III A/B NSCLC but no standard chemotherapy regimen/schedule has been established. In a previous phase I study (Brade et. al, ASCO 2008), we reported that pemetrexed was the first 3rd generation deliverable at full dose concurrently with full dose RT and cisplatin. This combination was further in this study. Methods: Starting April/07 to Aug/09, patients with unresectable stage IIIA/B NSCLC were entered on a single arm phase II trial at 5 Canadian centers. Eligibility: 1.3 l; adequate organ function. Staging PET scans were not routinely available. Patients received pemetrexed 500 mg/m2 day 1, cisplatin 20 mg/m2 days 1-5 q21 days × 2 concurrent with RT (61-66 Gy in 6-6.5 weeks) followed by pemetrexed/cisplatin alone × 2 q21 days (pemetrexed 500 mg/m2 day 1, cisplatin 75 mg/m2 day 1). Results: 39 patients were accrued. Demographics: median age: 63 years range 37-80; stage IIIA/B: 15/24; Histology: adenocarcinoma (21), squamous (10), mixed (1), large cell (1), NSCLC (6); median radiation dose: 65 Gy range 14.4-66. Four cycles of chemotherapy were delivered in 29/39 pts (3, 2 and 1 cycle in 3, 6 and 1 patient, respectively). Twenty of 39 patients experienced grade 3/4 toxicity deemed probably/definitely related to study therapy; 10 had grade 3/4 hematologic toxicity, primarily neutropenia; grade 3/4: 8/2 patients. Grade 3 non-hematologic toxicity was observed in 14 patients: nausea/vomiting 4; esophagitis 2; electrolyte alterations 5; fatigue/syncope 4. Grade 4 hypotension/syncope was seen in 1 patient. Grade 3 pneumonitis was observed in 1 patient, grade 2 pneumonitis in 4 patients. Median overall/progression-free survivals were 19.7/11.8 months, respectively. One year overall/progression-free survivals were 80%/47%, respectively. Conclusions: Full dose pemetrexed/cisplatin with full dose concurrent RT is relatively well tolerated and active in stage III/B NSCLC. These data provide support for an ongoing phase III registration trial (PROCLAIM) evaluating a similar regimen. Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Lilly Lilly