ASCO--Two randomized trials have shown that an oral serotonin antagonist,
granisetron (Kytril) tablets, is equal in safety and efficacy to an intravenous
drug of the same class in preventing emesis in patients undergoing emetogenic
In the first study, of highly emetogenic chemotherapy, presented at
ASCO by Richard Gralla, MD, 1,054 patients received either two 1 mg granisetron
tablets 60 minutes before an initial course of cisplatin (Platinol) or
32 mg of IV ondansetron (Zofran) 30 minutes before cisplatin administration.
Placebos were given to allow for blindedness.
Total control rates (defined as no nausea or vomiting and no additional
medication) at 24 hours were comparable for both groups: 55% for oral granisetron
and 58% for IV ondansetron.
"It is clear that Kytril tablets offer control of nausea and vomiting
comparable to intravenous therapy," said Dr. Gralla, director, Oschner
Cancer Institute, New Orleans. He also noted that in this study, the cost
of the oral agent ($62) was lower than that of the IV drug ($129).
In the second trial, involving moderately emetogenic chemotherapy, the
same drug regimens were given to 1,085 patients prior to an initial course
of cyclophosphamide or carboplatin (Paraplatin). Again, total control rates
were similar, said Edith Perez, MD, associate professor of medicine, Mayo
Clinic Jacksonville (Florida), in her ASCO presentation.
At 24 hours, 59% of patients on the oral agent had achieved total control,
compared with 58% of those on IV ondansetron. At 48 hours, the figures
were 47% and 44%, respectively.
In the cisplatin study, the most common adverse events--headache, asthenia,
and constipation--were similar in both antiemetic groups. In the cyclophosphamide/carboplatin
trial, the incidence of these side effects was similar in both groups,
while IV ondansetron-treated patients had a significantly higher incidence
of dizziness and visual disturbances.