The purpose of this study was to determine the objective response rate, median duration of response, time to disease progression, and survival time and to evaluate the safety of pegylated liposomal doxorubicin in previously treated patients with low-grade non-Hodgkin's lymphoma. Thirty-two patients with low-grade non-Hodgkin's lymphoma were treated and analyzed. Pegylated liposomal doxorubicin 30 mg/m2 was administered intravenously as a single dose on day 1 of each 3-week cycle. Patients had an Eastern Cooperative Oncology Group performance status of 0-1 and had stage II-IV disease. The median baseline left ventricular ejection fraction was 60%, and the median age was 68 years. In 29 evaluable patients, there were 3 (10%) complete responses, 6 (21%) partial responses, 11 (38%) patients with stable disease, and 9 (31%) with progressive disease. The median number of cycles was 4 (range, 1-22 cycles). The median duration of response (complete response plus partial response) was 11.0 months (range, 2.3-37.0 months). The estimated median time to progression was 5.6 months (range, 1.1-40.5 months) and the estimated median survival was 29.6 months (range, 3.9-41.6 months). Treatment-related toxicities grade = 3 included neutropenia (25%) and palmoplantar erythrodysesthesia (9%). Only 1 clinically significant cardiac toxicity was observed. There were 17 deaths; none were treatment related. Single-agent pegylated liposomal doxorubicin 30 mg/m2 every 3 weeks, is associated with antitumor activity in the treatment of low-grade non-Hodgkin's lymphoma, as shown by an objective response of 31%, and produced no significant cardiac or hematologic toxicity. Based on these results, pegylated liposomal doxorubicin should be further evaluated in combination with other agents in low-grade non-Hodgkin's lymphoma.