A combination of Platinol and either of two antimetabolites delivers the same punch against mesothelioma, according to a study.
The research, published in the Journal of Chemotherapy, compared a combination of Platinol (cisplatin) and Alimta (pemetrexed) with a combination of Platinol and Tomudex (raltitrexed). It was titled “Antimetabolites in the treatment of advanced pleural mesothelioma: a network meta-analysis of randomized clinical trials.”
When doctors are unable to operate on patients with metastatic pleural mesothelioma, the patients usually receive chemotherapy that includes Platinol and either Alimta or Tomudex. Bristol-Myers Squibb makes Platinol, Eli Lilly and Company makes Alimta, and Hospira makes Tomudex.
Antimetabolites are drugs that counteract the growth of cancer cells. Alimta and Tomudex are similar to folic acid in that they interfere with processes that allow cells to survive and grow.
No studies have indicated that either Alimta or Tomudex has an advantage when combined with Platinol. Doctors appear to have a slight bias toward Alimta, which may be the result of better marketing.
Researchers at the City Hospital in Remini, Italy, wanted to see if one of the two combinations was superior. They used a new approach — network meta-analysis of randomized clinical trials — to do an indirect comparison of the Platinol-Alimta and Platinol-Tomudex regimens.
The two clinical trials they used in their study had looked at whether a combination of either Platinol-Alimta or Platinol-Tomudex was more effective against mesothelioma than Platinol alone.
Both trial studies were published in the Journal of Clinical Oncology. One was titled “Phase III study of pemetrexed in combination with cisplatin versus cisplatin alone in patients with malignant pleural mesothelioma.” The other was “Randomized phase III study of cisplatin with or without raltitrexed in patients with malignant pleural mesothelioma: an intergroup study of the European Organization for Research and Treatment, of Cancer Lung Cancer Group and the National Cancer Institute of Canada.”
The Italian researchers determined the effectiveness of the two combo regimens by looking at the clinical trial patients’ overall survival rates at 10, 15, and 20 months. They also checked patients’ response rates and the therapies’ safety.
There was no statistically significant difference between the Platinol-Alimta and Platinol-Tomudex combos on patients’ survival or response rates, the meta-analysis showed.
Interestingly, there was a significant difference in side effects, with patients treated with the Platinol-Alimta combo having more. Those taking that combo were even at higher risk of developing severe or life-threatening side effects, the analysis showed. This was particularly true of hematological — or blood-related — side effects.
The researchers considered the regimens’ safety to be similar, however. Although there was a statistical difference in the side effects, they had an almost negligible impact from a treatment point of view, the team said.
Recent clinical trials have shown that a triple combo involving Platinol, either of the antimetabolites and Avastin (bevacizumab) could be a promising way to treat mesothelioma. The team said they look forward to the combination’s approval.