A new once-a-day morphine formulation appears to provide better control of cancer pain than an earlier twice-daily version of the agent, according to Canadian researchers.

Dr. Neil A. Hagen of the Tom Baker Cancer Center in Alberta, Calgary and colleagues note in the Journal of Pain and Symptom Management that twice-daily morphine offers several advantages over shorter-acting formulations. These include better compliance, more convenience and less fluctuation in drug levels in the blood.

The researchers undertook the current study to determine if a once-a-day formulation called MS Contin XL provided even greater benefits than the twice-a-day formulation.

The study involved 25 patients with chronic cancer pain who were randomly selected to receive either agent during different phases of the study.

Although the overall ability of the drugs to control pain was similar, MS Contin XL blocked the rise in pain scores seen during the day with the twice-daily formulation. Moreover, MS Contin XL was associated with less nausea.

When surveyed, 68 percent of patients said they preferred MS Contin XL over the twice-daily formulation for pain control.

The investigators conclude that the once-daily morphine capsules “provide a valuable therapeutic alternative for this group of patients.”

The research was supported by a grant from Purdue Pharma, the maker of MS Contin XL.

SOURCE: Journal of Pain and Symptom Management, January 1, 2005.