4 Recommendations for research

4.1 The results of ADMIRE‑CD showed that most patients tend to relapse within the first year after achieving remission and healing of the fistula in both arms of the trial. Unfortunately, there are limited data between year 1 and year 2 for data on relapse, and no data on relapse are available for year 2 and beyond. The committee considered that the outcomes of the ADMIRE‑CD and the ongoing ADMIRE‑CD II trial did not capture fully the relapsing-remitting nature of Crohn's disease with perianal fistulas. The new evidence submitted after consultation did not clarify the uncertainties around the long-term benefits of darvadstrocel compared with placebo either, because the results from the literature were very different from the results of ADMIRE‑CD.

4.2 Further research is recommended to resolve the uncertainties about the long-term clinical effectiveness of darvadstrocel compared with standard care. In particular, estimates of long-term remission rates (minimum of 2 years' follow‑up) in Crohn's disease with perianal fistulas are needed.

4.3 The health-related quality-of-life evidence of patients with perianal fistulas is also lacking, therefore further research is recommended. Any research should measure the effect of treatment using preference-based measures (such as use of the EQ‑5D questionnaire).

  • National Institute for Health and Care Excellence (NICE)