***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: At present, eligible first line trials for this meta-analysis were available for bevacizumab (5 trials including 3101 patients) and vatalanib (1 trial which included 1168 patients). The overall HR´s for PFS (0.61, 95% CI 0.45 - 0.83) and OS (0.81, 95% 0.73 - 0.90) for the comparison of first-line chemotherapy, with or without bevacizumab, confirms significant benefits in favour of the patients treated with bevacizumab. However, the effect on PFS shows significant heterogeneity. For second-line chemotherapy, with or without bevacizumab, a benefit in both PFS (HR 0.61, 95% CI 0.51 - 0.73) and OS (HR 0.75, 95% CI 0.63-0.89) was demonstrated in a single, randomized trial. While differences in treatment-related deaths and 60-day mortality were not significant, higher incidences in grade III/IV hypertension, arterial thrombembolic events and gastrointestinal perforations were observed in the patients treated with bevacizumab. For valatanib, currently available data showed a non-significant benefit in PFS and OS. The addition of bevacizumab to chemotherapy of metastatic colorectal cancer prolongs both PFS and OS in first-and second-line therapy.
Output:

Data from 5 randomized trials, which included a total of 3101 patients and evaluated the effect of bevacizumab, are currently available. Furthermore, data from one study, which included a total of 1168 patients and evaluated the effect of valatinib is published. The addition of bevacizumab to chemotherapy prolongs both progression-free survival from about 7.1 to 9.7 months when used as primary treatment and overall survival from about 17.7 to 20.5 months after prior use of chemotherapy (so called "second-line therapy") for metastatic colorectal cancer. However, the magnitude of the effect on progression-free survival is variable and probably depends on the type of chemotherapy to which it is associated. Vatalanib has no significant effect on progression-free and overall survival. Adverse effects of bevacizumab include increased frequencies of high blood pressure, arterial thromboembolic events and bowel perforations.