Pemetrexed in patients (pts) with relapsed small cell lung cancer (SCLC): A phase II study from the Hoosier Oncology Group

Abstract

7063 Background: Patients with relapsed SCLC have a dismal prognosis. Pemetrexed is a well tolerated agent, which is active against non-small cell lung cancer. We postulated that Pemetrexed may also be active and well tolerated in pts with relapsed SCLC, for whom few effective options exist. Methods: Eligible pts had small cell or a poorly differentiated neuroendocrine cancer, received 1 or 2 prior chemotherapy regimens and had an ECOG PS 0–2. Pts received Pemetrexed 500 mg/m2 iv once every 3 weeks along with vitamin B12, folic acid, and dexamethasone for up to 6 cycles or progressive disease or intolerable side effects. Chemosensitive (S) pts (relapse > 90 days following 1st line chemo) and chemoresistant (R) pts (PD ≤ 90 days following 1st line chemo) were analyzed separately. The primary objective of this phase II study was to estimate the clinical benefit rate [partial response (PR) or stable disease (SD)] in the 2 populations. Pts were to be accrued in 2 stages. If 8 of 18 and 3 of 21 pts achieved a PR or SD in the S and R populations, respectively, accrual would have continued to a total of 46 (S arm) and 50 (R arm) pts in each arm. Results: From 1/05 to 9/05, 43 pts were enrolled. Criteria to proceed to stage II were not met for either arm. S arm (n = 20): M/F 12/8; median age 63 (range, 45–79), PS 0/1/2 7/8/5. R arm (n = 23): M/F 17/6; median age 65 (range, 42–79), PS 0/1/2 7/10/6. Select grade 3/4 toxicities (combined group): 4 pts with neutropenia; 2 pts each with anemia, AST/ALT, bilirubin elevation; 1 pt each with thrombocytopenia, febrile neutropenia, infection with neutropenia, and rash. S arm: 1 PR and 1 SD were confirmed. R arm: 1 PR and 1 SD were confirmed. Conclusions: Pemetrexed 500 mg/m2 has minimal single agent activity in pts with relapsed SCLC. [Table: see text]