Spanish researchers led by Dr. Emilio Alba have been studying the effects of pegylated liposomal doxorubicin in a group of 155 women who had already been treated with chemotherapy.
At the 33rd Congress of the European Society for Medical Oncology (ESMO) in Stockholm, they present long-term follow-up data showing that 81% of patients prescribed the drug were alive after one year, compared to 66% of those who did not receive the treatment.
The aim of the therapy was to delay progression of disease while inflicting as few side-effects as possible, said Dr. Alba.
"Despite major advances in adjuvant therapy, the number of patients with metastatic breast cancer who are expected to relapse is substantial," he said. "In this setting the treatment is not curative, but it is important to explore all the available alternatives."
"In the case of chemotherapy, toxicity is the main drawback. Almost all studies carried out up to now associate maintenance therapy with a longer time-to-progression, and sometimes more overall survival. However, dealing with toxicity forces us to balance benefits and risks."
"The main finding of this trial was the low toxicity profile of pegylated liposomal doxorubicin at a dose of 40mg/m2. This dose presented no gastrointestinal toxicity, no grade IV alopecia, and grade IV adverse effects such as mucositis or hand-and-foot syndrome (HFS) were lower than 5%. The treatment also presented no cardiotoxicity. The subjective tolerance was very good."
Women treated with the drug saw a mean increase in time-to-progression of 3.4 months, the researchers found, which is similar to that of new targeted drugs such as trastuzumab or lapanitib. "While a month would probably fall short, a recent survey indicated 51% of oncologists would consider a time-to-progression increase of 3 months as successful," Dr. Alba said.
"Maintenance therapy is a good option for almost everybody, if we can design effective treatments associated with a good toxicity profile. I think this goal is achieved in the case of pegylated liposomal doxorubicin," he said.