Investigators announced the findings from phase 3 studies, which found that cisplatin plus an antifolate — either pemetrexed or raltitrexed — increase survival in patients with mesothelioma nearly 3-fold.
The latest findings from a number of trials were announced at the European Respiratory Society 2008 Annual Congress by Thierry Berghmans, MD, from the department of intensive care and thoracic oncology at Institut Jules Bordet, in Brussels, Belgium.
Two of the largest randomized trials involved nearly 500 patients with mesothelioma. In the first, 250 patients got either a combination of cisplatin plus raltitrexed or cisplatin alone. In the other, 243 patients with mesothelioma got pemetrexed plus cisplatin or cisplatin monotherapy.
Cisplatin was considered the best treatment option before the advent of the antifolate agents, Dr. Berghmans commented.
Progression-free survival was 5.7 months in the cisplatin-plus-pemetrexed group and 3.9 months in the cisplatin-monotherapy group. Median survival time was 12.1 months with combination therapy and 9.3 months with monotherapy. Overall risk reduction was 41.3% with pemetrexed plus cisplatin and 18.7% with cisplatin alone.
In the second trial presented at a press conference by Dr. Berghmans, first-line treatment with raltitrexed plus cisplatin was associated with a progression-free survival of 5.3 months, compared with 4 months for treatment with cisplatin alone. One-year survival was 46.2% with and 39.6% without raltitrexed.
Disease control occurred in 59.3% of patients in the pemetrexed and cisplatin group, compared with 19.2% in the cisplatin-monotherapy group.
“Cisplatin plus pemetrexed is the best treatment we’ve got for mesothelioma,” Dr. Berghmans asserted. “There is a positive response with a shrinking of tumor size.”
Surgery plus cryostatics plus radiotherapy is currently under investigation as another option, and it has shown promise in the first few patients, all of whom are younger patients with less-advanced disease.
“A decade ago, mesothelioma was considered a hopeless disease, with a mean survival time of 6 months. That is no longer the case,” Dr. Hillerdal said during closing remarks.
Dr. Berghmans’ studies were funded in part by Lilly Oncology, Ltd, which manufactures pemetrexed under the brand name Alimta. Dr. Hillerdal has disclosed no relevant financial relationships.
European Respiratory Society (ERS) 2008 Annual Congress: Poster P2636, Symposium. Presented October 7, 2008.
