In August TiGenix became the first company ever to report positive phase III data in an allogeneic stem cell therapy, delivering statistically significant results for Cx601 in the treatment of complex perianal fistulas caused by Crohn’s disease.
The full results will be presented at the European Crohn’s and Colitis Organisation meeting in Amsterdam next March, preparing the ground as Tigenix submits the file to the EMA in the first quarter of 2016, with approval and launch expected in the second half of 2017.
Adding to this notable first, TiGenix has an FDA Special Protocol Assessment (SPA), outlining exactly what data are needed to get US approval too – and putting the company on course to change the current treatment paradigm.
Around 11% percent of Crohn’s patients suffer fistulas, of which 70 – 80 percent are classified as complex. The lesions are usually recurrent and have a severe impact on quality of life.
In the randomised, double-blind, placebo-controlled phase III trial, a single injection of Cx601, which consists of adipose-derived stem cells, was statistically superior to placebo at week 24 in patients who had failed on previous therapies. The fistulas of almost half of the 103 patients who received Cx601 were in remission six months post-treatment.
The statistically significant result was all the more notable given that the 205 patients who took part in the study continued to receive standard of care. Given this, there was a high placebo response rate, of 35.6 percent. Even so, the p value was below 0.025, pointing to the statiscally superior therapeutic effect that Cx601 provides.
“The positive results, together with the FDA’s phase III SPA designation, means we can move ahead with making Cx601 available to the more than 100,000 patients who suffer from this serious condition,” Mr Bravo says.
The current care pathway starts with antibiotics, progressing to immunosuppression with steroid drugs, then anti-TNF alpha antibodies, and finally surgery. Remission rates are low and there is a high rate of relapse with each level of treatment. This highlights the potential contribution that Cx601 – effective after a single treatment – stands to make to both improving care and reducing treatment costs.
Importantly in an allogeneic treatment, there were no serious safety concerns in the phase III trial. Adverse reactions were evenly distributed between Cx601 and the control arm.
Mr Bravo hopes for a smoother path to commercialisation with Cx601, as an allogeneic product, than with the company’s other breakthrough advanced therapy, Chondrocelect, for repairing damaged knee cartilage.
The cartilage product was the first autologous cell therapy to be allowed on the market under the EMA’s Advanced Therapy Medicinal Products regulation, getting approval in 2009. However, difficulties with agreeing reimbursement and existence of cheaper copies in some important European markets have hampered market development.
As an allogeneic product, Cx601 presents fewer complications in terms of manufacturing and logistics than Chondrocelect. “We are bearing previous experience with Chondrocelect in mind as preparations for marketing Cx601 progress,” Mr Bravo says.
“We do have to convince the payers, but given the significant medical need for patients suffering from this severe condition and the positive results of our phase III clinical trial we are confident that we will have broad approval and reimbursement for Cx601”.