A phase II multi-institutional study of estra-1,3,5(10)-triene-3,17 beta-diol, 3-benzoate, 17[[4-[4-[bis(2-chloroethyl)amino]phenyl]-1- oxobutoxy]acetate] (KM2210), a novel antitumor agent, for advanced and recurrent breast carcinoma.
In order to evaluate the efficacy of Estra-1,3,5(10)-Triene-3,17 beta-Diol, 3-Benzoate, 17[[4-[4-[Bis(2-Chloroethyl) Amino]Phenyl]-1-Oxobutoxy] Acetate] (KM2210), a multi-institutional cooperative Phase II study was performed in patients with measurable advanced and recurrent breast cancer. Two hundred miligrams of KM2210, a conjugate of chlorambucil and 17 beta-estradiol, were administered orally daily for more than 4 weeks to each patient. According to the WHO criteria of response, 103 evaluable cases were assessed. Complete response was obtained in 9 cases, partial response in 19, no change in 39 and progressive disease was observed in 36. The overall response rate was 27.2% (28/103). The response rate was higher in patients without prior treatment than in those with prior treatment. However, KM2210 was also effective against breast cancers treated previously with tamoxifen, anthracyclines and their combinations, showing response rates of 25.5%, 22.0% and 29.6% respectively, suggesting that this agent is also effective on breast carcinomas which were insensitive to tamoxifen and anthracyclines. For efficacy classified in terms of metastatic lesions, the response rate was significantly higher in soft tissues than in other involved organs, and the response rate of bone metastasis was limited. Bone marrow suppression, including leukopenia and thrombocytopenia, was thought to be the dose-limiting toxicity of KM2210. Genital bleeding due to the released estrogen was observed as a characteristic side effect. KM2210 is considered to be useful for the treatment of advanced and recurrent breast cancer when administered at a dose level of 200 mg per day for more than 4 weeks.
Kubota
T
T
Department of Surgery, School of Medicine, Keio University, Tokyo, Japan.
Abe
O
O
Izuo
M
M
Watanabe
H
H
Enomoto
K
K
Ohsawa
N
N
Kuno
K
K
D000328:Adult; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy*; D002699:Chlorambucil / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004958:Estradiol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy*; D012074:Remission Induction
D000970:Antineoplastic Agents; D002699:Chlorambucil; D004958:Estradiol; C036613:bestrabucil