Phase II study of doxorubicin and bevacizumab for patients with metastatic soft-tissue sarcomas

To evaluate the antitumor activity and tolerability of bevacizumab and doxorubicin in patients with metastatic soft-tissue sarcoma (STS).

Patients may have had up to one nonanthracycline line of therapy. Seventeen patients with metastatic STS were treated with doxorubicin at 75 mg/m2 intravenous (IV) push followed by bevacizumab 15 mg/kg IV every 3 weeks. Dexrazoxane was started for total doxorubicin dose exceeding 300 mg/m2.

A total of 85 cycles of doxorubicin/bevacizumab were administered, median four cycles (range, one to 11), with three patients receiving one to four cycles of bevacizumab maintenance after reaching 600 mg/m2 doxorubicin. All 17 patients were assessable for response. Two partial responses (12%, 95% CI = 1% to 36%) were observed, lasting seven and 12 cycles of therapy. Eleven patients (65%) had stable disease for four cycles or more. Six patients developed cardiac toxicity grade 2 or greater, with four patients grade 2 (cumulative doxorubicin 75, 150, 300, 300 mg/m2, respectively), one grade 3 (total doxorubicin 591 mg/m2), and one grade 4 (total doxorubicin 420 mg/m2). One patient with extensive lung disease died of recurrent bilateral pneumothoraces, possibly treatment-related.

The 12% response rate for these patients was no greater than that observed for single-agent doxorubicin. However, the 65% of patients with stable disease lasting four cycles or longer suggests further study is warranted in STSs. The observed cardiac toxicity, despite close monitoring and standard use of dexrazoxane, obliges a change in the dose and/or schedule in future studies of this combination.