Polyglutamate Paclitaxel Compared With Docetaxel in Treating Patients With Progressive Non-Small Cell Lung Cancer

DISEASE CHARACTERISTICS: * Histologically confirmed non-small cell lung cancer (NSCLC) * Documented clinical or radiologic disease progression on or after initial systemic therapy * Must have received 1 prior platinum-based systemic therapy for NSCLC * Measurable or nonmeasurable disease * No evidence of small cell carcinoma, carcinoid, or mixed small cell/non-small cell histology * Brain metastases allowed provided patient received prior standard antitumor therapy for CNS metastases (e.g., whole brain radiotherapy, stereotactic radioablation, or surgery) and the following conditions are met: * No prior systemic chemotherapy as a radiosensitizer combined with radiotherapy * Obtained stable neurologic function at least 2 weeks before study entry * Off steroid therapy or on a tapering regimen * Recovered from prior therapy PATIENT CHARACTERISTICS: Age * 18 and over Performance status * ECOG 0-2 Life expectancy * Al least 16 weeks Hematopoietic * Absolute neutrophil count at least 1,500/mm\^3 * Platelet count at least 100,000/mm\^3 Hepatic * Bilirubin no greater than upper limit of normal (ULN) * Alkaline phosphatase no greater than 2.5 times ULN * AST or ALT no greater than 1.5 times ULN Renal * Creatinine no greater than 1.5 times ULN Cardiovascular * No unstable angina * No myocardial infarction within the past 6 months * No evidence of cardiac conduction abnormalities (e.g., bundle branch block or heart block) unless cardiac status stable for the past 6 months Other * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No evidence of unstable neurological symptoms in the past 4 weeks (2 weeks for neurological symptoms due to brain metastases) * No intolerance to excipients of polyglutamate paclitaxel (e.g., poly-L-glutamic acid, poloxamer 188, dibasic sodium phosphate, or monobasic sodium hydroxide) * No other unstable medical conditions * No clinically significant active infection * No neuropathy greater than grade 1 * No other concurrent primary malignancy except carcinoma in situ or nonmelanoma skin cancer * No circumstance that would preclude study completion or follow-up PRIOR CONCURRENT THERAPY: Biologic therapy * Not specified Chemotherapy * See Disease Characteristics * No prior polyglutamate paclitaxel * No prior docetaxel Endocrine therapy * See Disease Characteristics Radiotherapy * See Disease Characteristics * No concurrent radiotherapy Surgery * See Disease Characteristics * Recovered from prior major surgery Other * Recovered from prior therapy * More than 2 weeks since prior treatment for NSCLC * More than 4 weeks since prior investigational drugs * No other concurrent investigational drugs * No other concurrent systemic antitumor therapy * No concurrent amifostine * Concurrent bisphosphonates allowed