An intralesional injection of mesenchymal stem cells can significantly increase remission rates in patients with complex perianal fistulas associated with Crohn’s disease, an experimental study shows.
According to the authors of the Phase 3 randomised double-blind placebo controlled trial of 212 adults across 49 hospitals and seven countries in Europe and Israel their findings suggest that local treatment with Cx601 added on to established treatments for Crohn’s disease might open new therapeutic options for refractory perianal disease.
Professor Rupert Leong, Head of the Inflammatory Bowel Disease Service at Concord Hospital, said fistulising Crohn’s disease remained a difficult-to-manage phenotype associated with significant morbidity.
“A local stem cell based therapy is very attractive if patients are refractory to standard antibiotics and/or anti-TNF agents.
The alternative option includes surgical flaps, fistula closure devices and even diversion of faecal content via a stoma,” he told the limbic.
The study published in The Lancet found 50% of patients treated with the allogeneic adipose derived stem cells (Cx601) achieved the primary endpoint of combined remission within 24 weeks compared to 34% of patients receiving a placebo (difference 15·2%, 97·5% CI 0·2–30·3; p=0·024).
All patients continued to receive their background treatment.
Professor Leong said the research provided good preliminary data on a novel therapy and minimally invasive alternative to closure.
“The dose and the best regimen for the stem cells remains to be determined and further efficacy using higher doses might be possible. Durability of improvement also needs testing,” he said.
The allogeneic adipose-derived stem cells were well tolerated with mostly mild to moderate adverse effects including proctalgia and anal abscesses. Overall, 17% of the treated group reported adverse effects compared to 29% of controls.
The researchers said the technique could be performed in an outpatient setting by an experienced surgeon.
Writing in an accompanying editorial experts from the University of Pavia in Italy said the findings were an opportunity to “support the start of a new era in the treatment of fistulising Crohn’s disease through local injections of an industrial preparation of MSCs (Cx601) as first-line treatment, either alone or in combination with other therapeutic drugs.”
Professor Leong said the findings supported his own Phase 2 study of mesenchymal stem cells in the treatment of refractory luminal Crohn’s disease and other uncontrolled studies in perianal fistulising Crohn’s disease
He added that unlike haematogenous stem cells, mesenchymal stem cells lack HLA expression and therefore matching is not required.
“It will be interesting to see where, when and how these therapies will be applied through the PBAC and MASC system for approval and reimbursement,” he said.