Alefacept is a protein that limits specific activities of the immune system that are involved in causing psoriasis. In October 2004 alefacept (Amevive®) became the first biologic approved for the treatment of psoriasis in Canada.
It is thought that at least 10% of people with moderately severe psoriasis do not respond adequately to their current therapy or have experienced side-effects that prevent the continuation of treatment with a specific drug. These individuals run out of safe therapeutic options and are often frustrated with the medicines that they are prescribed because they do not achieve lasting improvement. Alefacept may be considered to treat this psoriatic patient population who are also candidates for systemic therapy or phototherapy.
How the treatment works
- Alefacept inhibits the activities of certain white blood cells in the immune system that trigger psoriasis.
- It is given by a healthcare provider as an intramuscular (into the muscle) injection.
- Usually administered once a week for a 12 or 16 week period, then a minimum of 12 weeks off, and then, provided laboratory tests show normal white blood cell counts, retreatment can proceed with an additional 12-week course.
- Very good safety profile
- Not everyone will respond adequately to treatment, but for those that do, significant improvement can be maintained for over 22 weeks after discontinuing therapy. Studies have shown that the average time before retreatment is required is 10 months.
- A problem with some of the biological drugs is a rebound of the disease after stopping the medication. This was not observed with alefacept.
- Low response rate
- Improvement is slow to occur
- Alefacept may reduce white blood cell (WBC) count. If the level of these WBCs falls too low, treatment may need to be suspended temporarily or discontinued.
- Alefacept may increase the risk of developing cancer. Tell your doctor if you have cancer or a history of cancer.
- Alefacept reduces certain immune system activities. As such, a weakened immune system can increase the risk of developing a new infection or reactivating a latent (inactive) infection.
- Common side-effects: cough, sore throat, dizziness, nausea, myalgia (muscle pain), chills, itch, injection site reactions
- More serious side-effects: lymphopenia (low WBC count), cancer, serious infections, hypersensitivity, transaminase (elevation of liver enzymes), cardiovascular events.
Comments & Suggestions
- To derive the most benefit from treatment, you must not miss a scheduled injection visit.
How Biologic Agents Work
- Be patient, as improvement may take 3 months or longer to occur.
- A major challenge for you and your doctor will be to find the ideal treatment regimen, which will likely include phototherapy (such as narrow-band UVB) in order to extend the durability of the improvement achieved by alefacept.
- Blood tests and other medical evaluations during treatment are necessary to monitor progress and side-effects
- Including the use of emollients and topical anti-psoriatic medication for early application on any relapsed area of skin will also help.
- Contact your doctor immediately if you develop symptoms of an infection such as fever or chills, sore throat, coughing, or burning with urination.