Olsalazine versus sulphasalazine for relapse prevention in ulcerative colitis: a multicenter study.
OBJECTIVE
To compare the relapse-preventing effect and the frequency of adverse events of olsalazine and sulphasalazine in sulphasalazine-tolerant patients with ulcerative colitis.


METHODS
Patients in remission, with at least two episodes of active disease during the last 5 yr, were randomized to 2 g of sulphasalazine or 1 g of olsalazine daily and were followed for 6-18 months. Relapse rates in the two groups were compared using frequency and life-table analysis. Sixty-nine patients with proctitis, 140 with left-sided colitis, and 113 with subtotal or total colitis were evaluated.


RESULTS
In the intention-to-treat analysis, the failure rate (relapses plus withdrawals) was 54.7% in the olsalazine and 47.2% in the sulphasalazine group. In the per-protocol analysis excluding withdrawals, 44.7% relapsed in the olsalazine and 39.3% in the sulphasalazine group. Remission curves did not differ significantly, although at all time intervals the frequency of remission was slightly higher in the sulphasalazine group (p = 0.19 in the intention-to-treat analysis and p = 0.42 in the per-protocol analysis estimated by the log-rank test). Twelve patients (of whom five had diarrhea) in the olsalazine group versus eight patients in the sulphasalazine group discontinued the study because of side effects.


CONCLUSIONS
The relapse-preventing effect of olsalazine and sulphasalazine in sulphasalazine-tolerant patients did not differ. Furthermore, the tolerability of olsalazine, particularly concerning diarrhea, appears to be better than previously reported.
Nilsson
A
A
Department of Medicine, Umeã Hospitals, Sweden.
Danielsson
A
A
Löfberg
R
R
Benno
P
P
Bergman
L
L
Fausa
O
O
Florholmen
J
J
Karvonen
A L
AL
Kildebo
S
S
Kollberg
B
B
D000328:Adult; D000636:Aminosalicylic Acids / Q000009:adverse effects / Q000627:therapeutic use*; D003093:Colitis, Ulcerative / Q000188:drug therapy* / Q000517:prevention & control; D003967:Diarrhea / Q000139:chemically induced; D004311:Double-Blind Method; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D015993:Life Tables; D008297:Male; D009664:Norway / Q000453:epidemiology; D012008:Recurrence; D012460:Sulfasalazine / Q000009:adverse effects / Q000627:therapeutic use*; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D016896:Treatment Outcome
D000636:Aminosalicylic Acids; D012460:Sulfasalazine; C032587:olsalazine