Potential MS Drug Cladribine Reported To Have No Impact on Cancer Incidence

A new study recently published in the journal Neurology: Neuroimmunology & Neuroinflammation revealed that the drug Cladribine does not increase the risk of cancer in patients with multiple sclerosis (MS) as previously thought. The study was led by researchers at Queen Mary University of London (QMUL) in the United Kingdom, and is entitled “No evidence for higher risk of cancer in patients with multiple sclerosis taking cladribine”.

MS is a chronic, progressive neurodegenerative autoimmune disorder that results from an attack on the central nervous system (brain, spinal cord and optical nerves) by the body’s own immune system, ultimately causing motor function impairment, irreversible neurological disability and paralysis. MS usually manifests in younger adults, and it can have a significant impact on the patient’s quality of life. It is estimated that more than 2.3 million people in the world suffer from the disease, including over 120,000 individuals in the United Kingdom, and upwards of 400,000 in the US.

Cladribine has been previously shown to be a highly effective therapy for patients with relapsing MS, resulting in a reduction of over 50% in relapse rate and no signs of disease activity in almost 50% of the patients analyzed (based on data from patients at the Barts Health NHS Trust in London, followed-up for two years). However, Cladribine failed to obtain market authorization due to the suspicion that it could cause cancer.

Now, researchers have compared clinical phase III trials data on cancer incidence among MS patients treated with Cladribine or other disease-modifying drugs currently licensed for MS. In total, data from 11 pivotal trials was analyzed, including 7 different MS drugs: Cladribine, natalizumab (Tysabri), dimethyl fumarate (Tecfidera), fingolimod (Gilenya), alemtuzumab (Lemtrada), glatiramer acetate (Copaxone) and teriflunomide (Aubagio).

Researchers found that relapsing MS patients under Cladribine treatment did not have an increased risk of cancer in comparison to patients under other MS treatments.

“Our research shows that clinical academics and drug makers should continue to develop Cladribine for people with relapsing MS as the risk of developing cancer is no greater than for other types of current medication,” said the study’s senior author Dr. Klaus Schmierer in a news release. “As well as being easier and cheaper to administer, Cladribine benefits female patients who want to get pregnant. Other drugs used to treat relapsing MS need to be stopped during pregnancy and that can expose women to increased risk of MS disease activity. That’s not the case with Cladribine, which has a long lasting effect.”

The authors concluded that Cladribine appears to be safer, more effective and easier to use when compared to other MS drugs. The team suggests that Cladribine should be again considered a potential MS therapy, and that further long-term follow-up studies should be conducted to determine the safety profile of the drug.