Phase II study of pegylated liposomal doxorubicin HCl (Caelyx) in combination with cyclophosphamide and vincristine as second-line treatment of patients with small cell lung cancer

BACKGROUND: Despite chemotherapy and radiotherapy for small cell lung cancer (SCLC), most patients die within 2 years. Response rates for second-line chemotherapy are 15-25%, with a median survival of 5 months. Caelyx, a pegylated liposomal formulation of doxorubicin, may be better tolerated and has activity in SCLC. PATIENTS AND METHODS: Thirty-two patients were enrolled in a phase II study of intravenous Caelyx (35 mg/m2), cyclophosphamide (750 mg/m2) and vincristine (1.2 mg/m2) every 21 days as second-line therapy in SCLC for up to six cycles. RESULTS: Thirty patients were evaluable for response, with a response rate of 10%. Another two had an unconfirmed response. Stable disease (SD) for >or=2 cycles was seen in an additional 53%. Grade 3 or 4 non-hematologic toxicity was seen in 17 (55%) patients (26 [22%] cycles) and included fatigue, mucositis, plantar-palmar erythrodysesthesia, rash and neuropathy. Twelve patients required transfusions. All patients on study have now expired, with a median survival of 28 weeks (7 months). For patients with SD or partial response, median time to progression was 15 weeks. CONCLUSION: The combination of Caelyx, cyclophosphamide and vincristine, despite cyclophosphamide and Caelyx dose reductions, has modest activity in relapsed SCLC with acceptable toxicity.