Cladribine Tablets Showing Efficacy in Clinical Trials for Patients With Highly Active Multiple Sclerosis
At the recent CMSC meeting (Nashville, May 30-June 2, 2018)- data from clinical trials from the CLARITY trial of cladribine tablets (investigational in US, marketed as Mavenclad in Europe; EMD Serono, Rockland, MA) for treatment of patients with multiple sclerosis were presented.
After 2 years of treatment, there was no evidence of disease activity (NEDA) in 43.7% of the subset of patients with highly active MS who were treated with cladribine tablets compared to 8.7% of patients treated with highly active MS who were treated with placebo (P =.0001). As the definition of NEDA can vary and no one factor alone is a sufficient indicator of MS disease activity, NEDA was defined as having no relapses, no increase in disability as measured by the expanded disability status scale (EDSS) and no newly enhancing lesions on MRI.
These results are consistent with other results from the CLARITY trial in which there was also a robust response and achievement of NEDA in patients treated with cladribine tablets compared to those treated with placebo. In the overall study results, 1,326 patients who had MS for 8 to 9 years on average were treated with cladribine or placebo and there was a 57.6% reduction in the rate of relapse, and after 2 years 79.7% of patients treated with cladribine tablets were relapse-free.
Another benefit of cladribine tablets, important in light of the recent American Academy of Neurology guideline that states patients’ treatment preferences should be considered, is that the drug is administered orally for just 10 days per year over 2 years in a weight-based dose. If approved in the US, it’s likely the dose will be 3.5 mg per kg per day for 10 days in each of 2 years. This is a very different dosing and treatment regimen from other therapies on the market currently. Such a time-limited oral treatment regimen is expected to reduce the burden of treatment for many patients and have a beneficial impact on medication adherence.
Cladribine is an adenosine substitute discovered first treatment for blood cancers and now showing efficacy in studies for treatment of patients with MS. It is taken up selectively by the T and B lymphocytes that stops cell division and in so doing provides a sort of reset for the immune system. Through that reset the autoimmune attack on myelin may be reversed. While T and B lymphocyte populations are reduced, none are completely eliminated, and risk of infection has not increased, with the exception of a small increase in the numbers of patients having herpes zoster.
John Walsh, Vice President for Neurology and Immunology at EMD Serono stated “EMD Serono has more than 20 years of experience in the market, and we have treated more than 140,000 patients now and have a patient support service in the US with a broad range of financial assistance programs. With our recent work on the investigational compound cladribine tablets we hope to bring even more options to the MS community. We remain committed to MS both with Rebif and hopefully with cladribine on the horizon as well as other drugs in our pipeline. This has given a new presence and strong commitment to MS and that’s what we are most excited about right now.”