Drugmaker Roche Holding AG said on Thursday its Xeloda oral chemotherapy was as effective as standard drugs in treating advanced stomach cancer, supporting analysts’ views of higher sales potential. Roche said data from a Phase III study due to be presented at an American Society of Clinical Oncology meeting (ASCO) showed that Xeloda, when added to another chemotherapy called cisplatin, was at least as effective as the intravenous chemotherapy drug, 5-fluorouracil.