Azathioprine or methotrexate in the treatment of patients with steroid-dependent or steroid-resistant ulcerative colitis: results of an open-label study on efficacy and tolerability in inducing and maintaining remission.

BACKGROUND

The role of azathioprine and methotrexate in inducing and maintaining remission in patients with ulcerative colitis is still controversial.

AIM

To evaluate the efficacy and tolerability of these two drugs in a series of patients with steroid-dependent or steroid-resistant active ulcerative colitis.

METHODS

Forty-two patients were treated with a daily dose of azathioprine (2 mg/kg) and, if intolerant or not responding, with methotrexate (12.5 mg/week intramuscularly), and their efficacy was established by clinical, endoscopic and histological examinations at 6 months. Patients achieving clinical remission continued with treatment and were followed up.

RESULTS

Of the 42 patients on azathioprine, 10 experienced early side-effects requiring withdrawal from treatment, 22 (69%) achieved complete remission, six (19%) achieved improvement and four (12%) obtained no substantial benefit. Methotrexate, administered to eight patients intolerant to and two patients resistant to azathioprine, induced complete remission in six patients (60%) and improvement in four (40%). During follow-up, a larger number of patients on azathioprine relapsed in comparison with patients on methotrexate [16/28 (57%) vs. 2/10 (20%), respectively; P < 0.05]. Only minor side-effects were observed on both treatments.

CONCLUSIONS

Azathioprine is effective in patients with steroid-dependent or steroid-resistant ulcerative colitis. Methotrexate seems to be a good alternative in patients intolerant to or not responding to azathioprine.