First-line, single-agent Herceptin(R) (trastuzumab) in metastatic breast cancer. a preliminary report.
Following confirmation of the appropriate dosage, safety and potential efficacy of Herceptin(R) (trastuzumab) in small-scale phase I and II trials involving patients with refractory disease, a large trial was conducted in 222 patients with breast cancer who had relapsed after one or two chemotherapy regimens for their metastatic disease. The results showed a positive and durable overall response rate (15% according to a response evaluation committee (REC) assessment) using trastuzumab monotherapy (initial dose 4 mg/kg intravenously (i.v.) followed by 2 mg/kg i.v. weekly). In another recently completed phase II trial, 113 patients were randomised to two dose levels (initial dose of 4 mg/kg i.v. dose followed by 2 mg/kg i.v. weekly, or initial dose of 8 mg/kg followed by 4 mg/kg i.v. weekly) of single-agent trastuzumab as first-line therapy for metastatic disease. The preliminary overall response rate was 23% based on investigator assessment, and tolerability was excellent as in previous trials; efficacy was similar in both dose groups, but the side-effects tended to be more frequent in the higher dose group. The preferred dosage is therefore the same as that currently recommended, i.e. an initial dose of 4 mg/kg i.v. followed by 2 mg/kg weekly i.v. until disease progression.
Vogel
C
C
University of Miami School of Medicine, Miami, FL, USA
Cobleigh
M A.
MA
Tripathy
D
D
Gutheil
J C.
JC
Harris
L N.
LN
Fehrenbacher
L
L
Slamon
D J.
DJ
Murphy
M
M
Novotny
W F.
WF
Burchmore
M
M
Shak
S
S
Stewart
S J.
SJ