Many anti-cancer chemotherapy agents have the unpleasant side effect of causing nausea or vomiting, and cisplatin therapy is perhaps one of the worst. Nausea from cisplatin follows a distinct pattern of both acute and delayed nausea; the acute phase refers to nausea experienced in the first 24 hours after treatment; and, the delayed phase refers to nausea experienced in days two through five after treatment.

Researchers from Merck Research Laboratories in Rahway, N.J., and from various cancer and medical institutions in Mexico and South America, studied whether MK-869 would be useful in preventing either acute or delayed nausea.

They evaluated 351 cancer patients who had not previously received cisplatin therapy and compared the effectiveness of MK-869 with that of a commonly used anti-nausea drug called granisetron. All patients received an additional anti-nausea drug called dexamethasone.

To evaluate the effectiveness of MK-869, the researchers divided the patients into four groups who received granisetron alone, MK-869 and granisetron, or two different schedules of MK-869 alone.

According to the researchers, "once daily oral administration of MK-869 was effective in reducing delayed emesis (vomiting) and nausea after high-dose cisplatin." Among patients who received MK-869, granisetron, and dexamethasone, 63% made it through the delayed phase without vomiting. In contrast, only 29% of the patients who did not get MK-869 made it through the delayed phase.

With regard to the acute phase, they found that the combination of granisetron and dexamethasone was more effective in reducing acute emesis than MK-869 plus dexamethasone, but a combination of all three drugs was most effective. When MK-869 was used with granisetron and dexamethasone, 80% of the patients made it through the acute phase without vomiting.

"We are still studying the specific issues that will provide optimal guidance to the use of this drug in patients," says Kevin Horgan MD, PhD, a research scientist with Merck involved in developing the drug, "but the development of this drug is an important fundamental scientific and medical advance," he adds.

"We are continuing to study MK-869 clinically for the prevention of chemotherapy-induced nausea and vomiting," Horgan says; "however, we are not in a position at this point to be able to define a time when it might be available to patients," he says.

Terri Ades, RN, American Cancer Society’s (ACS) director of health content, notes that "the importance of this study is that it shows the potential development of another effective anti-nausea medicine to help control the nausea and vomiting associated with chemotherapy."

"Twenty years ago, we had one or two anti-nausea medicines to use; then about 10 years ago, the number of effective anti-nausea medicines began to increase as we realized that too many patients’ nausea and vomiting were not being relieved," Ades says. "Thanks to clinical studies such as this one, we have been able to find new and effective medicines with either minimal side effects or ones that could be accepted by the patient as well as new combinations of existing medicines," she says.

"In order to improve the quality of patients’ lives, we must continue to find newer medicines and new combinations of medicines," Ades says. "Hopefully, MK-869 will be one that can be added to our growing list of effective anti-nausea medicines."