Ateam of European researchers recently reported
that the addition of oxaliplatin to the standard
regimen for advanced colorectal cancer of fluorouracil (5-FU) and leucovorin
doubled the response to therapy and significantly prolonged progression-free
survival, compared to leucovorin and 5-FU alone.
The standard regimen produces significant responses in 14% to
33% of patients. However, the average survival time of patients with metastatic
colorectal cancer is less than 1 year, and fewer than 5% live 5 years beyond
diagnosis. Oxaliplatin is the first drug in its class to show significant
activity in the treatment of advanced colorectal cancer. When used by itself,
oxaliplatin produces responses in 10% to 24% of patients with metastatic
colorectal cancer; however, researchers speculate that this agent may be more
effective in combination with other therapies.
Phase III International Trial Conducted
In order to evaluate oxaliplatin as first-line treatment in
advanced colorectal cancer, an international phase III clinical trial was
conducted in 420 patients aged 18 to 75 years at 35 institutions in nine
countries. Patients were treated with either the standard regimen of
5-FU/leucovorin or oxaliplatin combined with 5-FU/leucovorin.
The results of this trial, published in the August 2000 Journal
of Clinical Oncology, demonstrated that adding oxaliplatin to a regimen of 5-FU
and leucovorin doubled the number of patients with partial or complete responses
and prolonged the average time to disease progression by 3 months, compared to
treatment with 5-FU and leucovorin alone. Patients treated with oxaliplatin
survived an average of 9 months without progression, compared to only 6.2 months
for patients treated with 5-FU and leucovorin.
This trial demonstrated one of the longest progression-free
survival times of any multicenter trial evaluating treatment of metastatic
colorectal cancer. Over half of the patients treated with oxaliplatin survived
more than 14.7 months, compared to 12.1 months for patients treated with 5-FU
and leucovorin alone.