Current status of thiopurine analogues in the treatment in Crohn's disease

Table 1 Current status of thiopurine analogues in the treatment in Crohn’s disease: Take home messages

In Crohn’s disease treatment paradigms have been evolving in the last decades, with biological therapy becoming available

The efficacy of immunosuppressive therapy with purine analogues is well established in controlled trials (induction-maintenance, steroid-sparing agents, postoperative setting)

New data indicate that earlier use of immunosuppressants alone may be more effective in maintaining remission, reducing further corticosteroid exposure, and decreasing the risk of hospitalization and surgery

Adverse events during thiopurine therapy are frequent and lead to cessation of therapy in 9%-25% of patients

Despite intensive research, there is still controversy in the literature regarding the clinical relevance of thiopurine S-methyltransferase (TPMT) testing. Based on recent data, the determination of TPMT activity may be helpful in identifying high-risk patients for developing major complications, especially myelosuppression. In contrast, the negative predictive value is rather low, and it is not beneficial in ruling out the possibility of a side effect. Similarly, there is no established rationale to use TPMT activity for adjusting the dose of azathioprine to enhance therapeutic efficacy. For general practice, regular, frequent monitoring of clinical symptoms and laboratory check-ups continue to be recommended

Combination therapy with infliximab-azathioprine may have an added benefit in inducing steroid-free remission and mucosal healing compared to either infliximab or azathioprine alone, in azathioprine-naïve patients with early onset of disease

At present, the risks and benefits of combination therapy should be assessed on a per-case basis and should be discussed with the patient in the everyday clinical practice