Despite evidence that oral cladribine is effective in relapsing-remitting MS the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) has issued a negative opinion regarding the marketing authorization for Cladribine Tablets. The CHMP have concerns about the long-term safety of Cladribine.
In my opinion, long-term safety data can only be obtained from post-marketing surveillance studies and the extension study of the pivotal clinical trial. Unfortunately, there are probably not enough patients in the latter study to answer this question. It is a good thing that the drug is licensed in Russia and Australia.