How does it work?

Campath (alemtuzumab) is a drug which is effective at killing lymphocytes, which are a subset of the white cells in the blood that makes up the immune system. It is currently licensed for the treatment of leukemia. 

How is it administered?

An infusion into the blood stream once a year 

To what type of MS is it targeted?

Relapsing remitting MS 

Most recent trial results

The phase II clinical trial of alemtuzumab involved 334 people with early active relapsing remitting MS split into three groups comparing two doses of alemtuzumab against a control group taking beta interferon.

The results of the trial show alemtuzumab is much more effective than beta interferon. It is able to reduce relapse rate by at least 74 per cent compared to those taking beta interferon and, more importantly, the chance of accumulating disability over three years was reduced by at least 70 per cent compared to people taking beta interferon. Unfortunately, alemtuzumab is not effective at reducing disability progression for people with secondary progressive MS.
 

Current situation

Genzyme is currently running two large phase III trials in the UK and at other sites across the world. One compares campath with beta interferon in people who have previously not been treated for their MS, called the CARE MS I trial (ClinicalTrials.gov Identifier: NCT00530348)

The other is for people with MS who are receiving another therapy, but whose MS remains active called the CARE-MS 2 trial. The results are not expected before 2011 (ClinicalTrials.gov Identifier: NCT00548405). 

Side effects

The phase II trial was voluntarily suspended by FDA Sept 2004 after three cases of immune thrombocytopenic purpura (ITP) were reported. By this time most people had received two cycles of therapy. IPT is a disorder characterized by low numbers of platelets (cell fragments involved in the formation of blood clots) and corresponding increased risk of uncontrolled bleeding. Is potentially serious, but can be detected and monitored through blood tests and is usually treatable. 3 per cent (6 people) in the study have developed IPT to date.

Additionally, 16 per cent of people in the study developed thyroid-related side effects. The thyroid is a gland which controls how quickly the body burns energy, makes proteins and how sensitive the body should be to hormones. Tablets can be used to control these side effects. Other side effects include headache, rash, fever, depression, as well as temporary worsening of MS symptoms.