Actelion Pharma recently announced that it will accelerate the launch of clinical trials involving its lead drug candidate ponesimod, an oral, selective sphingosine-1-phosphate (S1P1). This decision came after a group of scientists working on different phases of clinical trials for the therapy observed mostly positive effects of ponesimod in terms of efficacy, efficiency and safety in comparison to other therapies.
Ponesimod acts by reducing the amount of infiltration lymphocytes in the bloodstream and lymph nodes. This is beneficial in the case of autoimmune disorders like multiple sclerosis (a neurological, autoimmune disorder, most prevalent in young adults, when a series of immunological pathways are activated and the body attacks its own central nervous system, causing degeneration of neurons), graft vs. host disease (following any stem cell transplant, where the body’s immune system ‘revolts’ against what seem to them as ‘pathogens’ and activates a cascade of immunological pathways) and systemic lupus erythematosus (a complex autoimmune disorder with unknown causes, mostly affecting women between ages 15 to 40, affecting the body’s innate and adaptive immune systems, and leading to the production of autoantibodies).
According to a recent press release by the company (dated 16th April, 2015), the clinical trials included initiation of a phase III clinical trial, OPTIMUM, for which patient enrollment soon begin. OPTIMUM is a multicenter, randomized, double-blind, parallel-group, active-controlled superiority study, comparing the efficacy of ponesimod against teriflunomide in controlling relapses in patients with multiple sclerosis.
Guy Braunstein, M.D. and Head of Global Clinical Development commented on this, stating, “The ongoing extension of the Phase II study, has provided a substantial amount of long-term efficacy and safety data with ponesimod in patients with multiple sclerosis, including some who have been treated for more than 5 years. In addition, we have identified a gradual up-titration dosing regimen that could mitigate the known first-dose effects of this class of drug. This regimen has been tested in a dedicated trial and the results will be presented in June this year.”
Adding on the efficiency of ponesimod, he said, “Ponesimod brings a number of unique properties, which include selectivity for the S1P1 receptor, rapid onset of action, a clear dose-response, and rapid reversibility upon discontinuation, an important option for physicians in case restoration of the immune system is required. We are convinced that — following regulatory approval – all these features and the data collected can make ponesimod an important oral therapeutic option.”
Another study on the verge of being executed is a phase II trial testing the effect of ponesimod in patients with graft vs. host disease on a dose-escalation basis. This will test the tolerance, pharmacokinetics and safety of the drug on patients who have responded inadequately to first and second line treatments.
A similar phase II trial testing the biological outcome of a dose-escalating study for patients with systemic lupus erythematosus.
Considering the complexity of autoimmune disorders, one can hope that these studies help in providing a cure for disease such as MS.
Jean-Paul Clozel, M.D. and CEO, Actelion, commented “Our efforts in the field of immunology have reached the necessary maturity to warrant fully-fledged clinical investigation. We have a thorough understanding of what selective S1P1 receptor modulators can bring to the clinic and have matched our compounds with the appropriate indication. We have carried out extensive groundwork and benefited from Health Authority input to design the optimal clinical program, which balances clinical risk, investment, medical need and commercial opportunity.”