Maintenance bevacizumab beyond first-line paclitaxel plus bevacizumab in patients with Her2-negative hormone receptor-positive metastatic breast cancer: efficacy in combination with hormonal therapy.
BACKGROUND
Data on efficacy of bevacizumab (B) beyond first-line taxane -including regimen (BT) as first-line treatment are lacking. Although preclinical results that anti-angiogenic agents combined with hormonal therapy (HT) could be active, no clinical data exist about combination of maintenance Bevacizumab (mBev) with HT.


METHODS
Thirty-five patients who experienced a response after first-line BT, were given mBev at the dose of 15 mg/kg every 3 weeks. Among 30 pts with hormonal receptor-positive metastatic breast cancer (MBC), 20 (66.6%) received HT with mBev (mHTBev). Objective of the study was the outcome and safety of mBev and in two groups of patients receiving HT or not.


RESULTS
Complete response and partial response was achieved/maintained in 4 (11.4%) and 13 (37.1%) patients, respectively (overall response rate: 48.5%). Clinical benefit was obtained on 23 patients (65.7%). Median of mBev PFS and clinical benefit were 6.8 months (95% CI: 0.8-12.7) and 17.1 months (95% CI :12.2-21.9), respectively. Median PFS of patients who received mHTBev was longer than mBev without HT (13 months and 4.1 months, respectively, p = 0.05). The most common severe toxicities were proteinuria (11.4%) and hypertension (8.5%). No additional toxicity was observed with HTBev.


CONCLUSIONS
Maintenance bevacizumab with or without anti-hormonal therapy in patients with hormone receptor positive breast cancer is tolerable and associated with long-term clinical outcome; these results encourage the strategy of prolonging bevacizumab until progression in combination with anti-hormonal agents.
Division of Medical Oncology A, Regina Elena National Cancer Institute, Via Elio Chianesi 53, Rome, Italy. alessandra.fabi@virgilio.it
Alessandra
A
Fabi
Michelangelo
M
Russillo
Gianluigi
G
Ferretti
Giulio
G
Metro
Cecilia
C
Nisticò
Paola
P
Papaldo
Ferdinando
F
De Vita
Giuliana
G
D'Auria
Antonello
A
Vidiri
Diana
D
Giannarelli
Francesco
F
Cognetti
D000328:Adult; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D000068258:Bevacizumab; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000401:mortality; D005260:Female; D006801:Humans; D060046:Maintenance Chemotherapy; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage; D011446:Prospective Studies; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D016896:Treatment Outcome
D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D018931:Antineoplastic Agents, Hormonal; D000068258:Bevacizumab; D017239:Paclitaxel; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone