Other names: alemtuzumab, Campath

Lemtrada is a disease modifying drug (DMD) for active relapsing remitting MS and very active relapsing remitting MS.

You take Lemtrada as an intravenous infusion (drip) in two treatment courses, twelve months apart. It reduces the number of relapses by about two thirds (70%), compared to taking placebo.

Common side effects include infusion-related reactions which are generally mild and short-lived and increased risk of infections following a treatment course.

Less common but potentially very serious side effects may also occur including thyroid disorders, kidney problems and blood clotting problems.

What is Lemtrada used for in MS?

Lemtrada is a disease modifying drug for active relapsing remitting MS and for very active relapsing remitting MS.  You have fewer relapses than you might have had without treatment.

Lemtrada is a highly effective (category 2.0) DMD; in clinical trials people taking Lemtrada had about 50% fewer relapses than people taking Rebif.  In clinical trials, people taking Lemtrada had fewer, smaller or no new areas of active MS (lesions).  Lemtrada may also slow down the build-up of disability associated with MS.

Who can take Lemtrada?

Lemtrada can be prescribed for adults with active relapsing remitting MS

Lemtrada has been approved for use on the NHS since 2014.  It can only be prescribed by a neurologist.

Conception and pregnancy

Pregnancy is not recommended during treatment with Lemtrada.  If you plan to start a family discuss your specific circumstances with your MS team.

Women of child-bearing age must use effective contraception during and for four months after a treatment course. 

If you become pregnant after treatment with Lemtrada and experience a thyroid disorder during pregnancy, extra caution is needed as thyroid disorders could be harmful to the baby.

How do I take Lemtrada?

You take Lemtrada as two treatment courses of intravenous (iv) infusions.

  • the first course consists of iv infusions on five consecutive days
  • the second course is taken 12 months later and consists of iv infusions on three consecutive days

In general you will be admitted as a hospital inpatient for the duration of each treatment course.

Most of the people who took Lemtrada in large clinical studies did not require additional treatment courses.  On-going studies are monitoring the requirement for retreatment in subsequent years.

What side effects could I get with Lemtrada?

Common side effects include:

  • infusion-related reactions such as headache, rashes, fever and nausea.

Most people treated with Lemtrada are affected by these reactions but they are generally mild to moderate and short-lived. To minimise infusion-related reactions, additional medications are given before infusions

  • infections including coughs, colds, chest infections and herpes virus infections (such as cold sores or shingles)

Lemtrada suppresses the immune system for some time after a treatment course so people will be more vulnerable to infections such as colds and viruses. To reduce the risk of herpes infections, an antiviral medication should be taken starting from the first day of infusion and continued for at least one month.

Three serious side effects have been reported from clinical trials

  • overactive or underactive thyroid gland leading to thyroid disorders
  • idiopathic thrombocytopenic purpura (ITP), a serious disorder which prevents blood from clotting
  • kidney problems

These side effects are potentially serious but are treatable if caught early enough. People taking Lemtrada will be informed of the early signs and symptoms of these side effects.

Common side effects (affecting more than 1 person in 100)

  • overactive or underactive thyroid
  • infusion associated reactions including headaches, rashes, fever and nausea
  • infections - respiratory and urinary
  • decrease in white blood cells (lymphopenia)
  • changes in blood pressure, heart rate
  • rash
  • musculoskeletal pain

Less common side effects (affecting less than 1 person in 100)

  • idiopathic thrombocytopenic purpura (ITP) a blood clotting disorder
  • kidney problems
  • thyroid disorders
  • increased levels of liver enzymes

A full list of side effects is included in the manufacturer's Patient Information Leaflet.

Assessment before treatment

Before starting Lemtrada, you should have blood and urine tests to measure blood cell counts and to check the function of the thyroid gland and kidneys.  You should also be tested for immunity against the virus that causes chickenpox and offered vaccination if you have not previously been exposed to the virus.

Assessment during treatment

Because of the serious nature of the potential side effects, it is vital that you have monthly blood and urine tests for four years after your last treatment course to monitor blood cell counts and to check the function of the thyroid gland and kidneys.  Depending on local practice, tests may be carried out at a local GP surgery or it may be necessary to attend a hospital clinic.

How does Lemtrada work?

Lemtrada works by binding to and killing immune cells (lymphocytes or white blood cells) which are involved when the immune system attacks myelin. It is thought that the cells which grow back after treatment do not cause damage to nerves.

Lemtrada research

What are the results so far?

Evidence for the effectiveness of Lemtrada has come from two large studies.

  • CARE-MS I - Lemtrada compared to Rebif in people who had not been treated with a DMD

This two year study compared Lemtrada and Rebif in 581 people in the first few years after diagnosis with relapsing remitting MS who had not been treated with a DMD.  Lemtrada reduced relapses by 55% compared to Rebif. There was no significant difference in disease progression between the two groups.

  • CARE-MS II - Lemtrada compared to Rebif

This two year study compared Lemtrada and Rebif in 667 people who had had at least one relapse while taking a DMD.  Lemtrada reduced relapses by 49% compared to Rebif.  The risk of disease progression was also reduced by 42% compared to Rebif, with 20% of the Rebif group showing an increase in disability compared to 13% of the Lemtrada group.

What further research is planned?

  • CAM-THY - Prevention of autoimmunity after Lemtrada treatment

Lemtrada works by binding to and killing T-cells (lymphocytes). 1 in 5 people develop an autoimmune disease after treatment; as their immune system grows back, it begins to attack other parts of their body, most commonly the thyroid gland. This trial will attempt to reduce the risk of autoimmune disease after treatment with Lemtrada by combining it with a second drug which alters the way in which the immune system grows back. Palifermin works by boosting the function of the thymus, a gland in the neck which makes new immune cells.
Estimated completion date October 2017.
Further details of this study.


  • National Institute for Health and Care Excellence (NICE). Alemtuzumab for treating relapsing-remitting multiple sclerosis [TA312]. NICE Technology Appraisal Guidance 312. Full guideline
  • Scottish Medicines Consortium (SMC). Advice: alemtuzumab (Lemtrada). Full guideline
  • Cohen JA, et al. Alemtuzumab versus interferon beta 1a as first-line treatment for patients with relapsing-remitting multiple sclerosis: a randomised controlled phase 3 trial. Lancet 2012;380:1819-28. Summary
  • Coles AJ, et al. Alemtuzumab for patients with relapsing multiple sclerosis after disease-modifying therapy: a randomised controlled phase 3 trial. Lancet 2012;380:1829-39. Summary

Last updated: 30 September 2015
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