Efficacy

Mavenclad (Cladribine) for Multiple Sclerosis

Mavenclad (cladribine) is an oral medication approved for the treatment of relapsing forms of multiple sclerosis (MS), including relapsing-remitting disease and active secondary progressive disease in adults. The efficacy of Mavenclad was demonstrated in clinical trials, such as the CLARITY study, which showed that cladribine significantly reduced the annualized relapse rate (ARR) in patients with relapsing MS compared to placebo. Additionally, the medication was found to reduce the risk of disability progression and the number of lesions detected by MRI scans, indicating its effectiveness in slowing down the physical and neurological impacts of the disease.

The mechanism by which Mavenclad exerts its therapeutic effects in MS is not fully understood, but it is known to induce a reduction in certain white blood cells, particularly lymphocytes, which are thought to be involved in the pathological process of MS. By targeting these cells, Mavenclad helps to modulate the immune response and reduce the frequency and severity of relapse episodes. However, due to its immunosuppressive action, the use of Mavenclad is generally reserved for patients who have had an inadequate response to, or are unable to tolerate, an alternate drug indicated for the treatment of MS.

Tysabri (Natalizumab) for Multiple Sclerosis

Tysabri (natalizumab), given as an intravenous infusion, is another medication approved for the treatment of relapsing forms of multiple sclerosis. Its efficacy has been established in several clinical trials, including the AFFIRM and SENTINEL studies. These trials have shown that natalizumab significantly reduces the ARR and the progression of disability in individuals with relapsing-remitting MS. Additionally, MRI findings from these studies have demonstrated that natalizumab can lead to a decrease in the number and volume of active brain lesions, which are characteristic of MS.

Natalizumab works by blocking the movement of potentially damaging immune cells from the bloodstream, across the blood-brain barrier, into the brain and spinal cord. This mechanism is believed to reduce the inflammation and damage that leads to the neurological symptoms of MS. While Tysabri is highly effective, it is associated with an increased risk of progressive multifocal leukoencephalopathy (PML), a rare but serious brain infection. Therefore, it is typically used for patients who have not responded adequately to other treatments for MS or for whom other treatments are contraindicated.