Biologics

Biologics are a new class of medications that has been developed within the past 10-20 years and has been revolutionary in treating many disease including rheumatoid arthritis, crohn’s disease and various cancers. They are essentially proteins that are developed in the lab that are used to serve a purpose in the body.

The first biologics are sometime we have all heard about – insulin. Before the advent of biologically derived insulin, most insulin was produced by purifying from animals including cows. This was an inefficient process and since the insulin from animals were somewhat different than human, many people suffered various side effected. Now that its use is common, we often forget the marked advantages of humanized insulin.

Most of the current biologics are used as “antagonists’. With our better understanding of our immune system, the medications are created to selectively block a pathway in our immune system with the hope of reducing the overactive immune response ( i.e. psoriasis) with the goal of having fewer side effects. However as with all therapies in psoriasis, these medications do not work for everyone and each has a certain failure rate.

Alefacept (Amevive) – this is the first biologic developed in the treatment of psoriasis. It works by blocking CD2 – a receptor that is found on many immune cells especially memory T-cells. Unlike other biologics, it is given in the muscle at 12 week intervals instead of a continuous treatment as other medications. After 12 weeks, you are assessed by your doctor to see how you are doing and whether you need more treatment. IT is not the most effective of the biologic treatments. However for those who do respond, some can stay clear for months without any treatment. IT does decrease one of your immune cells called CD4 and will need to be monitored by your doctor. The main concern of this medication is immunosupression resulting in infections.

Efalizumab (Raptiva) was the second medication developed for psoriasis. It has since been withdrawn from the market due to concerns of a neurological condition called progressive mult6icoal leukoencephalopathy. It is no longer available

TNF Inhibitors: The next three medications are a class of drugs called TNF inhibitors. This is one the few medications that treats both psoriasis and psoriatic arthritis by blocking a proinflammatory molecule called as TNF (tumor necrosis factor). The main concerned of this medication include infections (all types including TB), congestive heart failure, lymphoma and multiple sclerosis and should be discussed with your doctor.

Etanercept (Enbrel) is the third medications developed for psoriasis and currently the most commonly used biological for psoriasis. For those who live in my home town, it was developed in Seattle (a little hometown pride). Doctor Bernard Goffe and Philip Mease were one of the first to use it in psoriasis patients resulting in a dramatic change in psoriatic therapy. It is given at home by you, just under the skin at 50 mg twice a week. After three months, the dose is changes to once a week. Many people do get an injection site reaction – redness in the areas of the injection. This is usually temporary

Adalimumab (Humira) is the fifth drug that was developed to treat psoriasis. Like Enbrel, it works to block TNF and thus also works to treat psoriasis and psoriatic arthritis. It is also given at home under the skin. However after an initial series of two shots and one shot a week after, the medication is given every two weeks. Injection site reactions can also occur and is temporary
Infliximab (Remicade). This is the forth drug developed for psoriasis. Unlike the other TNF inhibitors, Infliximab is given by IV through the veins and thus must be given in the doctor’s office. The infusions are performed more initially at weeks 0, 2, 6 but then every 8 weeks after that. The infusion can take between 3 to 5 hours. Since it is given intravenously, infusion reactions can occur.

Ustekinumab (Stelera) was just recently approved for the treatment of psoriasis. This medication blocks another molecule called IL12/23. What is most attractive of this medication is its dosing schedule. It is given under the skin at the start, one month later and then every 3 months. Once the medications starts working, it may only require 4 shots a years to keep someone clear. Currently you will be required to get the medications at your doctor’s office. The main concern of this medication is immunosuppression resulting in infections.