Ca Pain Patients Appear to Prefer 12-hr Sustained-Release Morphine

MONTREAL-In a small Canadian study of patients with cancer-relatedpain, nearly 75% said that 12-hour dosing with sustained-releasemorphine sulfate tablets (MS Contin) offers advantages over 8-hourdosing, and nearly all (94.5%) preferred 12-hour to 4-hour dosing,report Gérard G. Mignault, MD, and colleagues from theHôtel-Dieu de Mon-tréal and Purdue Frederick, Pickering,Ontario, manufacturer of MS Contin.

This double-blind, randomized, crossover trial enrolled 27 patientswith a diagnosis of cancer-related pain of moderate or severeintensity who were already stabilized on oral opioids. The 19eval-uable patients were crossed over from 12-hour dosing to 8-hourdosing (or vice versa) after 5 days of administration. Blindnesswas maintained by giving placebo tablets so that each patienttook medication four times a day. Supplemental oral morphine solutionwas available for episodes of breakthrough pain.

Pain intensity and pain relief were measured four times each dayusing a 10-cm visual analog scale; occurrence and severity ofcommon opioid side effects were measured on a scale of 0 (none)to 3 (severe).

The results showed no advantage for 8-hour dosing in terms ofpain intensity, pain relief, adverse event severity, and use ofrescue morphine (J Pain Symptom Manage 10:416-422, 1995). Theresearchers pointed out that a small number of differences weredetected (for pain relief and individual adverse events) on specificdays, but these were not consistent at any given assessment timeor overall.

The investigators note that their trial confirms results fromother studies indicating that less than 10% of patients are likelyto require MS Contin more frequently than every 12 hours. Theyrecommend that the 8-hour dosing schedule be used only if thepatient has reproducibly shown breakthrough pain at the end ofthe 12-hour dosing interval, despite appropriate dose titration,or if side effects reproducibly occur within the first few hoursof a 12-hour schedule.

Dr. Mignault's colleagues in the study were Jean Latreille, MD,Francis Viguié, PhD, Pierre Richer, MD, and Francois Lemire,BSc (Pharm), from the Hôtel-Dieu de Montreal, and ZoltanHarsanyi, MBA, and John H. Stewart, MSc, from Purdue Frederick.