Rheumatoid arthritis drugs in development

A cure for rheumatoid arthritis may not be on the immediate horizon. But you may be encouraged to know that some promising rheumatoid arthritis drugs are being developed.

While you manage the signs and symptoms of your rheumatoid arthritis, researchers continue their work to better understand what causes the inflammation and joint damage of the disease and what can be done to relieve the pain and discomfort. However, despite developments there's still no cure for rheumatoid arthritis.

However, researchers are discovering and testing new rheumatoid arthritis drugs. And promising developments in rheumatoid arthritis drugs may soon allow your arthritis to be treated earlier, more effectively and with fewer side effects. Research into new rheumatoid arthritis drugs is focusing on a number of areas.

Rheumatoid arthritis drugs that target your immune system

Researchers hope to create rheumatoid arthritis drugs that target specific parts of your immune system, such as those that might trigger joint damage and inflammation. For instance, a drug may be used to reduce the amount of a certain protein that's believed to cause inflammation. Or a drug could be employed to induce your body to make more of a protein that halts inflammation. These types of rheumatoid arthritis drugs are sometimes referred to as biological response modifiers.

Biological response modifiers already used in treating rheumatoid arthritis include rituximab (Rituxan), abatacept (Orencia) and the TNF-alpha inhibitors adalimumab (Humira), etanercept (Enbrel) and infliximab (Remicade). Other biological response modifiers being investigated include the following.

New TNF-alpha inhibitors
Researchers are continuing to study new agents that block tumor necrosis factor-alpha (TNF-alpha), a cell protein that causes inflammation. One newer TNF-alpha inhibitor under investigation is prepared with a chemical that allows the drug to last longer in your body, so injections may be needed less frequently. The drug, certolizumab, is also being studied in Crohn's disease, an inflammatory disorder that affects the intestinal tract. Early studies in rheumatoid arthritis have shown promise, though more study is needed.

Drugs that block protein signals that cause inflammation
Certain proteins act as signals, telling cells to cause inflammation. Reducing the number of these proteins or blocking the receptors that receive their signals might help control rheumatoid arthritis. Researchers are investigating a number of targets, including:

• Interleukin-6 (IL-6). This protein causes inflammation by working with TNF-alpha, though it isn't clear how. TNF-alpha inhibitors block some of the signals sent by IL-6, but not all. Researchers are studying new drugs that may completely block IL-6 from being able to transmit its signals. One investigational drug, tocilizumab, attaches to the receptors that accept signals from IL-6, so the messages can't get through. Early studies show promise, but side effects such as elevated cholesterol levels and increased risk of infection have been noted.
• Interleukin-15 (IL-15). This protein attaches to receptors on cells to activate inflammatory processes in the lining that surrounds your joints (synovium). People with rheumatoid arthritis have high levels of IL-15 in the synovium of affected joints and in their blood. Researchers are studying a drug that intercepts IL-15 in your body so that it can't reach the receptors. Though results are promising, more study is needed to determine whether this drug is safe.

Drugs that stop B cells from causing inflammation
B cells — a type of white blood cell — cause joint inflammation in people with rheumatoid arthritis, though it isn't clear how. Researchers hope reducing the number of B cells in your body may reduce inflammation. A recently approved drug, rituximab, intercepts B cells and stops them from completing their tasks. Several other approaches to stopping B cells are under investigation. One investigational drug, belimumab, blocks signals that drive B cells. Early studies have had mixed results.

Drugs that prevent inflammatory proteins
Several different proteins play a role in causing inflammation. Rather than block just one at a time, researchers hope that they can turn off the master switch that creates these inflammatory proteins. A number of drugs are being developed to target a chemical called p38 mitogen-activated protein (MAP), which helps create inflammatory proteins such as TNF-alpha and IL-6.

Drugs already approved for other conditions

Some drugs approved for other conditions have been found to control inflammation in the body, which leads researchers to think that these drugs may be useful for people with rheumatoid arthritis. Some drugs approved for other conditions that are being studied for rheumatoid arthritis include:

• Antibiotics. Some evidence shows that antibiotics such as minocycline and doxycycline, may slow bone loss and reduce inflammation in people with rheumatoid arthritis. Study results have been mixed.
• Tacrolimus (Prograf). Tacrolimus is an immunosuppressant that blocks the action of T cells — a type of white blood cell that plays a role in activating other cells in your immune system. Tacrolimus is already approved for people who've had liver or kidney transplants — it keeps their immune systems from attacking their new organs. Researchers hope tacrolimus can help people with rheumatoid arthritis by stopping T cells from causing inflammation.
• Cholesterol-lowering drugs. Commonly referred to as statins, these cholesterol-lowering drugs have been found to reduce some indicators of inflammation in laboratory studies. Studies of statin drugs in people with rheumatoid arthritis have shown some promise, but not as much benefit as standard treatments. More study is needed to determine whether statins could play a role in rheumatoid arthritis treatment.
• Drugs that stop bone loss. Researchers hope to slow bone destruction in people with rheumatoid arthritis by stopping cells that break down bone (osteoclasts). Drugs called bisphosphonates interfere with osteoclasts and slow bone loss in people with bone diseases such as osteoporosis. A powerful bisphosphonate called zoledronic acid (Zometa), which is used to treat people with certain bone marrow cancers and cancers that have spread to the bone, is being tested in people with rheumatoid arthritis.

Gene therapy

Specific genes in your body might direct cells to manufacture substances that help reduce inflammation or protect your joints. The goal of gene therapy is to increase the production of these protective substances. It might mean supplying your body with a healthy gene to replace a defective one. Or it might involve blocking the action of a harmful gene. Though researchers have identified some helpful genes, they have yet to figure out the best way to deliver the genes' protective benefits. Very small studies performed in people have shown some promise, but gene therapy is still many years from being used for arthritis treatment.

New drug development: Research and approval take years

It takes several years for drugs to move from a new idea, through research and development and, eventually, to approval. Some drugs that seem promising in small studies don't work out in larger clinical trials and may never receive approval. Talk to your doctor as new drugs come on the market. Together you can decide what's best for you.