Relapsing Remitting Multiple Sclerosis
Multiple Sclerosis (MS) is a disease of the central nervous system that affects 2.3 million people world-wide. It is caused by an autoimmune reaction that damages nerve cells. This damage to the nerve cells interrupts signals and results in a wide range of symptoms that can affect movement, eyesight and cognition.
Around 85% of people who are diagnosed with MS have relapsing remitting MS (RRMS).
Treatment
There is no cure for MS, but some RRMS patients respond well to Disease Modifying Therapies.
Disease modifying therapies are drugs which can reduce how many relapses someone has and how serious they are. They can also slow down the damage caused by relapsing multiple sclerosis that builds up over time. The current most efficacious DMTs are called Alemtuzumab, Ocrelizumab, Cladribine and Ofatumumab.
Alemtuzumab
Alemtuzumab can be prescribed for very active relapsing remitting MS.
Alemtuzumab works by binding to and killing T and B cells, which are involved when the immune system attacks the covering around the nerves in your brain and spinal cord (myelin). This stops these cells from getting into your brain and spinal cord before they can damage the nerves there.
Most people only need to take the drug twice, in two courses spaced a year apart from each other. It's given through a drip (known as an infusion) in hospital.
The first course consists of IV infusions on 5 consecutive days
The second course is taken 12 months later and consists of IV infusions on 3 consecutive days
Ocrelizumab
Ocrelizumab can be prescribed for active relapsing remitting, very active relapsing remitting MS and early primary progressive MS.
Ocrelizumab has been designed to target a particular marker (CD20) on the surface of B cells, a type of white blood cell which is thought to be involved when the immune system attacks the myelin around nerve cells. The targeted B cells are destroyed.
Ocrelizumab is given through a drip, usually in a hospital clinic.
The first dose is given as two separate infusions, two weeks apart.
Further doses are given as one infusion every six months
Cladribine
Cladribine can be prescribed for highly active relapsing MS.
Cladribine acts by killing specific types of white blood cells (T and B cells) made by the immune system.
Cladribine is designed to prevent T and B cells from accessing the brain and spinal cord, so they cannot damage the nerves.
Cladribine is taken in the form of a tablet over two treatment weeks across two years. One treatment week at the beginning of the first month and one week at the beginning of the second month.
Each treatment week comprises 4 or 5 days in which a patient receives a single daily dose tablet (10mg or 20mg) depending on body weight.
Ofatumumab
Ofatumumab can be prescribed for active relapsing MS.
Ofatumumab acts by destroying B cells, the cells which damage nerves in MS. The drug minimises the amount of inflammation shown on MRI scans.
Ofatumumab is administered by injection (under the skin) with an initial dose at weeks 0, 1 and 2 followed by subsequent monthly doses starting at week 4.
Recently, Autologous Haematopoietic Stem Cell Therapy (aHSCT) has shown promise for treating a number of autoimmune diseases, including RRMS.
Haematopoietic stem cells are young cells that have the potential to become mature immune cells. These cells are collected from patients, by a process called mobilisation. The patients then undergo chemotherapy to wipe out their overactive immune cells (conditioning), before the stem cells are infused back into the bloodstream.
There is growing clinical evidence that aHSCT can treat RRMS more effectively than DMTs. However, as most data is registry based and previous trials did not directly compare aHSCT with the most efficacious DMTs, Alemtuzumab, Ocrelizumab, Cladribine and Ofatumumab, questions remain over the relative efficacy and safety of aHSCT over the UK standard of care for highly active RRMS. The StarMS trial aims to address these questions.