All About Remicade (Infliximab)
What is Remicade?
Remicade is an entirely new type of drug for Crohn's disease... a real breakthrough. It is an antibody that blocks a substance called TNF. (TNF stands for "Tumor Necrosis Factor" - but this has nothing to do with tumors or cancer.) This newly discovered protein has been found in the blood of patients with active inflammation like Crohn's disease and Rheumatoid Arthritis. In Crohn's disease, it is felt that TNF plays an important role in causing inflammation and damage of the intestinal wall. In fact, evidence to date strongly suggests a central role for TNF in Crohn's disease. Overproduction of TNF may lead to a flare-up of Crohn's symptoms. Why this occurs is just some individuals is still a mystery.
A biological agent is a "designer molecule" made to hit a specific target. Remicade is a new biological agent that was made to target only TNF. It is co-produced in mice and the final product is about 75% human and 25% mouse antibody. Remicade helps control the symptoms of Crohn's disease by binding to TNF and neutralizing its action. Because Remicade blocks TNF in Crohn's patients, it is sometimes called an "anti-TNF antibody." Remicade was approved by the FDA in May 1998 for treatment of Crohn's disease. It was recently also approved to treat patients with Rheumatoid Arthritis whom also seem to have an excess amount of TNF in their joints.
Who should receive Remicade?
Remicade is currently reserved for patients with active signs and symptoms of Crohn's disease who fail to adequately control their disease with convential therapy - prednisone, Pentasa, Asacol, Imuran, etc.
How is Remicade administered?
Unlike most medications for Crohn's, Remicade is given as a solution by intravenous infusion (into a vein). This infusion may be given in your doctor's office, or at an infusion center, or in an outpatient setting your doctor selects. The actual infusion takes 2 hours. You should plan on spending about 3 hours, which includes preparation. During this time, the nurse will check on you at regular intervals. The infusion is not sedating and most patients are able to drive home. Current dosage recommendations are:
What are the benefits of Remicade?
- For moderately to severely active Crohn's disease without fistulas, a single infusion is recommended
- For Crohn's patients with fistulas, three infusions (an initial infusion, then one 2 weeks later and one 6 weeks later) are recommended
This is a new drug and there is much to learn - especially about the risks and benefits. Short term studies look promising. One recent study of 108 patients reported that 4 weeks after one dose, 82% of people who received the recommended dose had improvement in the signs and symptoms of their Crohn's disease, compared to only 16% of the people who received a placebo. Almost half experienced complete disappearance of their Crohn's symptoms at one month.
Healing of intestinal fistulas
Another indication for Remicade is to help close intestinal fisulas. Common in Crohn's disease, a fistula is simply an abnormal "tunnel" that makes a path between two body cavities - such as between intestine and vagina, intestine and bladder, or from the intestine and through skin. One way a fistula may form is from an abscess - a pocket of pus in the body. The abscess may be constantly filling with body fluids such as stool or urine, which prevents healing. Eventually the fistula breaks through to the skin, another body cavity, or an organ. Fistulas are more common in Crohn's Disease than in ulcerative colitis. Approximately 30% of people with Crohn's Disease develop fistulas.
Until Remicade, there really was no generally effective medical therapy to help close a fistula. Antibiotics work only sometimes and major surgery was often required. Recent information suggests that Remicade may be of benefit in this situation. One clinical study looked at the effects of Remicade on healing of fistulas in 94 patients with Crohn's disease. About 68% of patients receiving the recommended dose of Remicade had at least half of their fistulas close for at least 1 month, compared to 26% of people who received a placebo. About 55% of patients had all of their fistulas close for at least 1 month, compared to 13% of people who received a placebo.
Can you predict which patients will best respond to Remicade?
No. As you see above, not every patient responds to this medication. It would be helpful to predict in advance who will respond and who will not. There have been a number of attempts to determine which Crohn's patients will likely benefit. So far, initial studies have been unable to determine specific factors that would predict a beneficial response. The only way to find out is to try it.
What if I have a stricture in my small intestine?
Remicade probably won't help. The natural history of Crohn's disease is to form ulcers on the inner intestinal wall which heal and then return over and over. Each time an ulcer heals some scar tissue (fibrosis) is formed. This scar tissue can accumulate over time and cause a narrowing in the small intestine or colon. This is called a stricture. A significant percentage of individuals may develop intestinal obstruction, or "blockage of the bowels," from these strictures. Remicade works best in reducing active inflammation, but has little effect on scar tissue which may be permanent. Reports have demonstrated that individuals who have intestinal strictures are less likely to respond to Remicade.
How long does Remicade last
The bad news is that this beneficial effect seems temporary. While Remicade has been shown in medical studies to heal the lining of the intestine, a single dose has been shown to provide full benefit for only 8 to 12 weeks, on average. Still, about 20% of patients still show a positive effect at 44 weeks.
What are the side effects?
In medical studies, most people had no side effects related to Remicade. Remicade infusions are usually well tolerated. Immediate side effects occur in about 5% of patients and include headache, nausea, itching, stinging, dizziness, fatigue, and fever and did not last long. Only 2% of people had to stop the infusion because of side effects. The infusion-related reactions, if they occurred, were typically mild, requiring reduction of infusion rate, administration of acetaminophen, and/or Benedryl. Pretreatment with Tylenol and Benedryl may be of benefit. Serious infusion-related reactions are uncommon, but can occur. That is why it is best to have the infusion in a controlled safe environment.
Some patients develop antibodies to Remicade that may result, rarely, in the development of a lupus-like syndrome. Recent data show this to occur in less than 1% of patients. Symptoms included migratory joint pain, pleuritis, and rash. There were no kidney or central nervous system symptoms. These symptoms resolved by simply stopping treatment and a short couse of steroids.
Rarely serious side effects may occur. Since this treatment partially blocks your immune system, patients treated with Remicade may have an increased risk of infection. The infections most frequently reported were upper respiratory tract infections (including, sinusitis, pharyngitis, and bronchitis) and urinary tract infections. Rarely, serious infections have been reported in patients, some fatal. You should not take Remicade if you have an acute or chronic infection.
Can Remicade give me cancer?
In the short term, no. Despite some intitial concerns, recent studies show no statistically significant increased incidence of cancer in individuals who were treated with Remicade compared with controls in the Crohn's disease studies or in all studies. This is a new drug. Of course, long term safety studies are ongoing.
What does Remicade cost?
This novel medication is very expensive. Of course, there is no generic substitute. The usual dose is 5 mg per kilogram of weight adminstered over a two hour infusion. The average 70 kilogram person (154 pounds) would require 350 milligrams. The cost of this infusion would be about $2500. When given for proper indications, most insurance carriers will cover all or part of the cost. This varies by insurance company, so preauthorization is usually required.
What about my other medications?
Most patients remain on the medications they are already taking for Crohn's disease - but started to see improvement in signs and symptoms after their Remicade infusion. Each case is different and only your doctor can determine what is right for you. Remicade is easily incorporated into your treatment program. Specific studies on drug interactions with Remicade have not been conducted. Be sure to let your doctor know all the medications you take, not just the ones you take for Crohn's disease.
Remicade is a new and powerful drug that seems promising for many Crohn's sufferers. As of February 2001, over 150,000 individuals have received Remicade treatment. There have been many success stories. Of course, it's not possible to predict in advance how you will respond to treatment with Remicade or how long the benefit will last. Side effects are usually minor, but serious side effects can occur. Long term effects will not be understood for several decades. It's important to discuss all of your treatment options with your doctor before deciding on any course of treatment.