Weekly alternating therapy with irinotecan plus cisplatin and etoposide plus cisplatin in the treatment of patients with extensive small cell lung carcinoma

BACKGROUND

Irinotecan has significant activity in small-cell lung cancer (SCLC). The authors' previous phase 1 study of alternating weekly therapy with irinotecan/cisplatin (IP), etoposide/cisplatin (EP), and granulocyte-colony-stimulating factor (G-CSF) support was well tolerated and active in patients with SCLC. A phase 2 trial was conducted to estimate the efficacy of this regimen in previously untreated patients with extensive SCLC.

METHODS

A total of 33 patients were treated between June 2002 and July 2007. Patients received 12 weeks of therapy with cisplatin (20 mg/m(2)) on Day 1 and irinotecan (100 mg/m(2)) on Day 1 and G-CSF on Days 2 to 5 (Weeks 1, 3, 5, 7, 9, and 11) followed by cisplatin (20 mg/m(2)) on Day 1 and etoposide (60 mg/m(2)) on Days 1 to 3 with G-CSF on Days 4 to 7 (Weeks 2, 4, 6, 8, 10, and 12). The primary endpoint was 1-year survival rate.

RESULTS

Grade 4 neutropenia (toxicities were determined using the National Cancer Institute Common Toxicity Criteria [version 2.0]) was noted in 5 (1.5%) of 343 courses with neutropenic fever in only 5 (1%) of 343 courses. One patient died of neutropenic sepsis. Nonhematologic toxicities grade >or=2 were observed in 15 (4%) of 343 courses and were limited to fatigue, hyponatremia, and diarrhea. The overall objective response rate was 89% in 28 assessable patients (no complete responses and 25 partial responses). The median progression-free and overall survivals were 6.0 months and 10.9 months, respectively. The 1-year survival rate was 33%.

CONCLUSIONS

Weekly therapy with IP alternating with EP and G-CSF support was well tolerated in patients with extensive SCLC, but did not demonstrate improved progression-free or overall survival when compared with historical controls at the study institution.

Phase II study of pemetrexed in combination with carboplatin in the first-line treatment of advanced nonsmall cell lung cancer

BACKGROUND

The primary objectives of this study were to determine the efficacy and tolerability of a pemetrexed-carboplatin combination as first-line therapy in patients with advanced nonsmall cell lung cancer.

METHODS

Eligibility criteria included Zubrod performance status of 0 or 1, Stage IIIB (malignant effusion) or IV disease, and no prior chemotherapy. Treatment was pemetrexed 500 mg/m2 given intravenously and carboplatin area under the serum concentration-time curve = 6 given intravenously on Day 1 every 3 weeks for six cycles; patients could receive additional cycles at the discretion of the treating physician and patient. All patients received folic acid, vitamin B12, and dexamethasone prophylaxis.

RESULTS

Fifty patients (31 men and 19 women) were treated. The median age was 62 years. Ninety-six percent of patients had Stage IV disease, and 88% had a performance status of 1. The median number of cycles was 6; 15 patients received 8 or more cycles. There was Grade 3/4 neutropenia in 11 (22%) and 2 (4%) patients, respectively; Grade 3/4 thrombocytopenia in 1 (2%) and 0 patients, respectively. Three patients (6%) experienced Grade 3 nonhematologic side effects (diarrhea, neutropenic pneumonia, and fatigue). No patients had sensory neuropathy or alopecia >Grade 1. The partial response rate was 24%, median time to progression 5.4 months, 1-year survival 56.0%, and median survival 13.5 months.

CONCLUSIONS

This is an active, very well-tolerated regimen. Trials focused on how to integrate this doublet with novel agents are warranted.

Phase I Study of Weekly Alternating Therapy with Irinotecan/Cisplatin and Etoposide/Cisplatin for Patients with Small-Cell Lung Cancer

The combination of IP (irinotecan/cisplatin) has been shown to confer a survival benefit compared with EP (etoposide/cisplatin) in patients with extensive-stage small-cell lung cancer (SCLC). Based on this and potential synergy from sequential inhibition of topoisomerases I and II, we conducted a phase I study to assess the feasibility of weekly therapy alternating IP and EP. The doses of EP were fixed (etoposide 60 mg/m2 on days 1-3 and cisplatin 20 mg/m2 on day 1). The dose of irinotecan was escalated in serial cohorts at 3 dose levels: 80, 90, and 100 mg/m2 on day 1. Granulocyte colony-stimulating factor was given on days 2-5 and days 4-7 after IP and EP, respectively. Patients with limited-stage SCLC received chemoradiation during weeks 4-6 with etoposide 120 mg/m2 on days 1-3, cisplatin 60 mg/m2 on day 1, and thoracic radiation 1.5 Gy twice daily in 30 fractions. Patients received 12 weeks of therapy. To evaluate dose escalation in subsequent cohorts, dose-limiting toxicity (DLT) was initially assessed during weeks 1-3 of treatment. Characteristics of the 18 patients accrued are as follows: performance status 0/1, n = 9; female sex, n = 9; extended-stage SCLC, n = 16; and median age, 53 years. Four patients treated at irinotecan dose level 1 (80 mg/m2), 6 patients at dose level 2 (90 mg/m2), and 6 patients at dose level 3 (100 mg/m2) did not experience DLT in weeks 1-4 and completed therapy without major incident. The only 2 patients to experience DLT during weeks 1-4 were treated at dose level 2. Both were hospitalized during week 4 and subsequently died. However, patients had already been accrued at dose level 3 and tolerated therapy well. Therefore, the trial design was modified to assess DLT during weeks 1-4, and additional patients were cautiously added to the dose level 2 and 3 cohorts. Analysis of summary toxicity data resulted in a recommendation that dose level 3 be used in phase II based on the probability of DLT of 16% (95% CI, 3%-29%). Responses in 16 evaluable patients include complete response in 1 patient, partial response in 14 patients, and minor response in 1 patient. With the exception of the 2 deaths, the therapy was well tolerated and active. Phase II evaluation of the regimen in patients with extensive-stage SCLC is ongoing.

Dose-dense therapy with a novel irinotecan regimen for small-cell lung cancer

Irinotecan (CPT-11, Camptosar) has significant activity in small-cell lung cancer. In addition, preclinical models have demonstrated synergy between irinotecan and two standard front-line drugs for small-cell lung cancer: cisplatin and etoposide; phase III data also show significant survival benefit for irinotecan/cisplatin compared to standard treatment. These data suggest a potential clinical advantage to combining etoposide, cisplatin, and irinotecan as first-line therapy for small-cell lung cancer. The purpose of this phase I study was to establish if alternating weekly therapy with irinotecan/cisplatin and etoposide/cisplatin was tolerated and to determine the maximum tolerated dose of these agents in patients with small-cell lung cancer. Patients generally tolerated the weekly alternating chemotherapy with irinotecan/cisplatin and etoposide/cisplatin well, and this combination possessed significant antitumor activity in small-cell lung cancer.