Inflammatory Arthritis - RA

Disease Process RA

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RA Essentials

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RA Disease Process leading to RA begins in the synovium the soft, membrane(synovial lining or intimal layer)that surrounds a joint and creates a protective sac. This sac is filled with lubricating liquid,the synovial fluid.
 
In addition to cushioning joints,this fluid supplies nutrients and oxygen to cartridge,a slippery tissue that coats the end of bones.
 
Cartridge is composed primarily of type II collagen, (and proteoglycans) the structural protein in the body, which forms a mesh to give support and flexibility to joints.
 
In RA,its integrity,resilence and water content are all impaired. This appears to be due to elaboration of proteolytic enzymes (collagenase, stromelysin) both by synovial lining cells and by chondrocytes themselves. Polymorphonuclear leukocytes in the synovial fluid may also contribute to this degradative process.
 
Bone; Composed primarily of type 1 collagen,invading synovium causes erosions of contiguous bone via release of prostaglandins and proteases by synovial cells and possibly,by osteoclasts.
 
Synovial Cavity; Normally only a "potential" space with 1-2 ml of highly viscous (due to hyaluronic acid) fluid with few cells. In RA,large collections of fluid ("effusions") occur which are,in effect,filtrates of plasma (and,therefore, exudative-i.e.,high protein content).
 
The synovial fluid is highly inflammatory. However,unlike the rheumatoid synovial tissue that is infiltrated with lymphocytes and macrophages but not neutrphils,the predominent cell in the synovial fluid is the neutrophil.
 
Subintimal area of the synovium; This is where the synovial blood vessels are located,this area normally has very few cells.
 
In RA however,the subintimal area is heavily infilterated with inflammatory cells,including T and B lymphocytes,macrophages and mast cells. The intense cellular infiltrate is accompanied by new blood vessel growth (angiogenenesis).
 
In RA,an abnormal immune system produces destructive molecules that causes continuing inflammation of the synovium. Collegen is gradually destroyed, narrowing the joint space and  eventually damaging bone.
 
If the disease develops into a form called progressive RA,destruction to the cartridge accelerates fluid and immune system cells accumulate in the synovium to produce a pannus,a growth compound of thickened synovial tissue.
 
The pannus can be thought of as a tumor-like tissue(although mitotic figures are rare and,of course,metastasis does not occur) produces more enzyme that destroy nearby cartridge, aggravating  the area and attracting more inflammmatory white cells, thereby escalating the process
 
This inflammatory process not only affects cartridge and bones but can also harm organs in other parts of the body--it is part of the immune system.
 
The immune system is a natural defense against invaders such as bacteria, viruses,and even cancer. The cells of the immune system recognize and respond to invaders or by attacking invaders directly. Although the immune system is normally activated by a foreign agent,it can be activated to attack normal cells.
 
In RA,for unknown reasons,the immune system becomes activated and causes marked inflammation of the synovial memberane-the thin synovial membrane becomes inflamed and filled with cells called lymphocytes, macrophages, polymorphs,and fibroblasts (cytokines)--pannus. This process does not occur in O.A.
 
The normally thin synovial membrane which normally is only 1-3 cell layer thick. In RA,this lining is greatly hypertropied (8-10 cell layer thick). Primary cell populations in this layer are fibroblasts (primitave white blood cells) and macrophages.
 
This layer can be felt by a arthritis specialist who are trained to feel this manifestation. It becomes squishy like "bread-dough".
 
As RA progresses,these abnormal cells begin to invade and destroy the cartilage and bone within the joint. The surrounding muscles, ligaments, and tendons that support and stabilize the joint become weak,and unable to work normally. All of these effects lead to the pain and deformities often seen in RA.
 
The inflammation is called synovitis,and it results in the warmth, redness, swelling, and pain that are typical symptoms of RA. During the inflammation process,the cells of the synovium grow and divide abnormally,making the normally thin synovium thick and resulting in a joint that is swollen and puffy to the touch.
 
Normal synovium lines,and is anchored to,both sides of the joint. The hypertrophied rheumatoid synovium begins its invasion of bone at these sites of attachment and this is seen radiographically as erosion, the height of cartilage is progressively and symmetrically reduced, consistent with a degradative process from exposure to synovial fluid (neutrophil mediated) or within cartilage (chondrocyte mediated).
 
Swelling is caused by thickening of the synovial membrane and sometimes by increased fluid or debris within the joint. Increased blood flow to the inflamed joint results in heat and redness.
 
Stiffness, commonly called "morning stiffness", occurs in almost all inflamed joints after a period of rest or disuse. This is particularily common in RA.
 
Morning stiffness can last from a few hours to all day long. To regain normal mobility inflamed joints must be loosened up by applying heat or doing exercise.
 
Many of the drugs used to to fight RA have anti-bacterial and/or anti-immune activity.Although we do not know the cause of RA,joint damage  is caused by inflammation in the synovial membrane.
 
RA is the most significant treatable cause of disability in the Western world. If left untreated,RA may lead to serious damage and disability.
 
Fortunately there is a window of opportunity for preventing disability in RA, If the disease is treated early,it can be controlled in most people.
 
Effective treatment depends on early recognition,a knowledgeable doctor,and proper treatment. Early treatment can make a lot of difference in the world,but treatment no matter when,will make a difference.
 
RA does not affect everyone in the same way. Just as different people have different personalities. Some will have mild-moderate and some severe form of the disease.
 
Historically RA was classified in terms of how it interfered in terms of how it interfered with normal everyday functioning.
 
Normal function-Mildly limited function-Moderately limited function-Severely limited function (disabled). and by bone damage caused by the disease that shows up on a x-ray film: Normal bone-Some bone damage-Moderate bone damage-Extensive bone damage. This classification shows how much damage the inflammation associated with RA has already done, but it does not help to show how severe or how fast your RA will progress.
 
The course of RA could be better classified by type: Mild-Moderate-Severe and by its duration (how long it has been present):
 
Early (less than 2 years)--the best time for treatment.--Progressive-The majority of patients at this stage have intermittent or steady progression of the disease and need continuing treatment. Controlled- when the symptoms of the disease have subsided or have been successfully treated.
 
When determining the type of a patient's RA.the following should be considered:The severity. Is the arthritis mild,moderate or severe? Is it charachterized more by "stiffening" than by "swelling"?
 
The features other than those that affect the joints,or extra-articular features.(EAFs): Extra-articular features are more often present in moderate and severe disease. They are usually absent,in the mild type. The level of rheumatoid factor,an antibody found in the blood that has known effect in the immune system,is partially related to the severity of RA.
 
Patients with moderate or severe disease activity usually have much higher levels of the R.F. than people with the mild form.
 
However,20% of people with RA,never develop a rheumatoid factor. The HLA -DR4 gene may be important in predicting the type,the severity, and the future course of RA(mild type usually,do not have it).
 
Laboratory tests such as C-reactive protein (CRP),which measures inflammation,and the bone density test may also increase the accuracy of predicting the course of RA--but the tests are not used everday in clinical practise.
 
In most patients,the type or temperament of RA diagnosed at the onset persists for the entire course of the disease.
 
However,in some patients,the course does change. This usually happens early in the disease,before the full features of either moderate or severe RA have developed, making them difficult to distinguish from the mild form of the disease.
 
 Unfortunately,the disease most often "comes in quitely and goes out with a roar". The opposite is rarely true. It is uncommon for moderate or severe disease to become mild without treatment.
 
Rheumatoid arthritis is an inflammatory disease as opposed to non inflammatory osteoarthritis. RA causes joints to swell,they become stiff,they become very sore.
 
To have a inflammatory respose is quite normal. If we cut ourselves,have surgery,there will be some redness, some swelling about the areas, an that's quite a normal part of the healing response.
 
But in people who have rheumatoid arthritis, something has gone awry and that inflammatory response starts for unknown reasons,and it continues,it doesn't go away.
 
It stays day in and day out. And then instead of that inflammatory response helping to heal,this actually can cause harm in the body.
 
Scientists have learned a lot about the inflammation in rheumatoid arthrits in the last several years.
 
They don't know what triggers it to begin it,but they have learned a lot about what happens.
 
They have learned a lot about the cells that are involved,a lot of immune cells;cells called T-cells,macrophages,B-cells,and they have learned a lot about their function and see that they are in many cases overactive and actually responding as they would initially in an acute inflammatory response,where there has been some injury to the body and then they see that they just keep going.
 
They have learned a lot about,how the inflammatory cells talk to each other and interact with each other,and about certain triggers that may activate them.
 
They have learned in the inflammatory response a lot about the cascade of events that happens,and they know a lot about the players in that cascade, cytokines or proteins.
 
They have learned a lot about what causes damages to the joints as far as what they have learned about enzymes,proteins that can help to cause some destruction. And these are often released in response to inflammation.
 
Scientists still,don't exactly know what triggered the inflammatory response.
 
We have learned that rheumatoid arthritis is not just a benign process that causes the joints to hurt.
 
 We know,now,that RA is a disease that causes a fair amount of damage to joints,and it can start causing that damage within the first couple of years.
 
We know that there are certain patients who may respond better to very aggressive treatment early on.
 
We have learned a lot about markers and the individual patient to help us profile patients,as to who is going to have more severe disease,or who is going to have a more slow,not as damaging or disabling course.
 
What you are starting to see with some of our newer therapies is that knowledge learned is starting to translate into earlier treatment of disease,more aggressive treatment of the disease early on in the course.
 
We are starting to see therapies that reflect our knowledge about inflammation and the various players and how we can interact in a different way with those players in the immune and inflammatory response than that we have in the past,and hopefully get a better outcome.
 
The newest category of medications that are currently used are drugs that inhibit cytokinesis. Cytokines are the proteins that cells use to signal from one to another.
 
Now,scientists have a better understanding of those signals,so they can understand which ones they want to turn off to try to shut the process down.
 
One of the most important seems to be is a cytokine called TNF-tumour necrosis factor, and they are beginning to (find) drugs now that can block the signallying, that blocks the TNF from getting from one cell to another where it's supposed to be going.
 
Enbrel or etanercept is a viable receptor for TNF--essentially it soaks up excess TNF in the joints between the cells,prevents it from getting to the cells that it's trying to reach and in the process slows down or shuts down the inflammatory process in the cells.
 
The outcome of that is reduced inflammation,reduced pain,and hopefully reduced damage to the joints in the long run. Remicade(infliximab) uses another method of blocking TNF(produces antibodies against TNF).
 
There is another cytokine called interleukin-1,which works in a similar fashion in the inflammatory process. Kineret or anakinra is the drug recently approved by the FDA to target interleukin-1. Kineret may be more suited as a additive to another drug used in therapy,such as MTX.
 
In Remicade's case scientists were able to engineer a TNF antibody through genetric engineering. An agent that cling onto TNF.
 
They have taken TNF inject into animals (mouse) to make a antibody against it,purify,humanize and infuse it into the body. Remicade will bind to TNF irreversibly. Once bound,it permanently disables TNF. It is given as a intravenous infusion,or IV every 8 weeks.
 
Enbrel also binds to TNF but it binds to it reversibly.TNF will bind and unbind,or disassociate from Enbrel. Remicade resides in the blood longer than Enbrel Also Remicade binds to TNF only.Enbrel is administered by an injection under the skin,and is given twice a week(subcutaneous injection).
 
Remicade is referred to as a monoclonal antibody. Enbrel utilizes the receptor for TNF to block ("sop-up" excessive TNF) its biologic activity.The objective for both drugs is to inhibit TNF.
 
The antimalarial agent hydroxychloroquine and cloroquine have been used since the 1950s to treat inflammatory disorders,including systemic lupus and rheumatoid arthritis.
 
Soon after their introduction for chronic use, concerns rose about their ocular safety. The first report formally linking chloroquine to retinopathy appeared in The Lancet in 1959 and has been followed by many others describing choloroquine-associated toxic effects on the eye. Reversible deposition of chloroquine salts in the cornea is common,but the most serious ocular effect is irreversible retinopathy charachterized by a "bulls-eye" maculopathy with paracentral or centre visual-field scotomata.
 
Early detection by opthalmological examination is critical because cessation of treatment generally arrest progression of the retinopathy. On the basis of these points therapeutic regimens emphasising low daily doses and regular ophthalmoligical monitoring have been suggested for both chloroquine and hydroxychloroquine (HCQ).
 
However,confusion about the risks of HCQ has resulted from the failure by early researcher- investigators to distinguish between HCQ and chloroquine when reporting ocular toxicity,and this has led to the longstanding perception that both agents require equally vigilant opthalmological follow-up . Although the association of chloroquine with retinophathy is now widely accepted,it is increasingly evident that HCQ is substantially less toxic.
 
It is clear that the risk of retinopathy among patients receiving appropiate doses of HCQ is vanishingly low, especially during the first 6-7 years of therapy,and it may equal that of untreated patients. On the basis of existing knowledge, one recommendation should be that HCQ dose,do not exceed 6.5 mg/kg lean body mass. Ophthalmological monitoring need not be started until the patience's tolerance of the drug is established and a long therapeutic course is likely.
 
The drug ;is relatively safe but is not recommended for moderate-severe therapy regimen in RA patients in that group because of the possible,lack of efficacy for those patients. It may be more suitable when the disease course is unknown or questionable, to ensure some form of DMARD therapy until a more established prognosis has occurred.
 
Whether HCQ provides joint protection is unclear,some experts claim it does,others differ. Clinical trials up to now have not clarified the point in question.
 
Sulfasalazine has been used more in Europe. Although its mechanism of action is unknown, studies have shown it controls RA.
 
Sulfasalizine begins working after 4 to 6 weeks of therapy,faster than gold or HCQ. It is also well tolerated;the most frequent side effects are gastrointestinal pains, nausea, malaise, dizziness,and headaches.
 
However,allergic skin rashes and a decrease in all blood cells do occur. Most side effects occur during the first 3 months of treatment.
 
Sulfasalazine is usually taken as a daily dose of 2 to 3 grams. Ideally the dose is increased slowly; 500 mg daily during week 1; 1000 mg daily during week 2; 1500 mg during week 3;and 2 grams during week 4. Blood test should be scheduled monthly for the first 3 months; then every 3 months.
 
In some cases sulfasalizine has been combined successfully with methotrexate and hydroxychloroquine. Since sulfasalizine may interact with other drugs,review your medicine with the physician Sulfasalazine is a fast-acting,moderately effective,less toxic DMARD; its beneficial effects may decrease more rapidly then other DMARDs.
 
Unfortunately RA often gets treated in a uniform manner without consideration of the severity of RA. Each RA suffer is different. Individual differences must be considered when a treatment plan is devised.
 
Treatment with drugs singly or in combination, at full therapeutic doses is essential for the best efficacy. Full doses have the best chance of controlling RA in the majority of patients
 
Combinations of the three drug types, NSAIDs, DMARDs,and steriods,often work better than a drug used singly,especially with the moderate and severe types of RA. Aggressive treatments works best.
 
If one treatment program fails,another should be implemented promply. Each patient have a slightly different response to inflammation, probably due to our unique genetric makeup,and this may make us less likely to react to various drug groups.
 
Initial failure with one group tells the doctor little,the experience may affect the patient negatively,stop trying, or feel discouraged, exactly when an alternative plan should be tried.
 
It is not sufficient to know how the drugs are used generally in all patients,but to use them specifically in particular cases.
 
This is where communication with the physician comes in play. Effective and informative conversation will assist the MD in determining the course of treatment to pursue.
 
Recent studies in patients with early RA have shown that combining lower doses of several DMARDs may be better than using one DMARD at high dose.
 
 Currently evidence suggests that MTX  combined with HCQ and/or sulfasalizine may be effective for people who do not respond to one drug alone. On-going research is been done to help determine the best combination.
 
Combination therapy is used more in the moderate-severe typ of RA. Biologics are ideal,but the high cost is the limiting factor.
 
Mild RA usually starts with NSAIDs or mild DMARDs such as HCQ. Moderates always start wit DMARDs or even combination DMARDs. Severe RA should always start with DMARDs or a combination.

Most patients with the mild disease will always have the mild form of the disease,and only rarely will they suffer joint damage. In many mild RA patients is sporadic characterized by flare-ups and subsequent remissions. In mild disease,the main aim of therapy is to stop the inflammation with the milder,safer drugs,like the NSAIDs,and when required (i.e. during a flare up),a DMARD.
 
In the past,most patients with moderate disease eventually developed damage to joints and tissue DMARDs,which can bring about remission have significantly changed the outcome in most RA patients. Moderate RA,can now usually be controlled,thus limiting the damage.
 
Severe RA is the type that has given the reputation as a "crippler". The severe type is usually diagnosed at  onset,but not always. Severe-moderate may regress to another type,but mild normally stays mild.
 
A patient with the more aggresive disease will require more medical attention and assistence from the health support team. If DMARDs in combination do not work,the next step is the newer biologic drugs.Confusion on which drugs to use can be damaging to the patient.
 
Significant differences between the treatment approach to mild, moderate and severe disease must be considered. NSAIDs,DMARDs and steriods must be harmonized appropriately.
 
The patient and the physician must make informed choices as to what is the best treatment in an individual case.
 
Lack of focus,delay in getting treatment, and slow or inappropriate treatment will seriously undermine the process to get the disease under control. A disease under control means minimal pain and RA fatigue.
 
Since the disease can be extremely aggressive, the treatment should be early and aggressive. The outdated practise of waiting for disease progress then adding DMARDs is gone.
 
It misses the opportunity of disease control.Holding off till damage or deformity appears is nonsense.
 
Predisone is a two-edged sword in that,as well as being effective in controlling inflammation, it can cause significant side effects over time.
 
If needed,it should be used for the shortest time as possible and the lowest dose for efficacy,with protection from the possible, resulting effects of osteoporosis.
 
Protection from ulcers is vital in the case of older NSAIDs. Patients usually assume that if they have no symptoms they are fine,but this is not true. The first sign may be bleeding.
 
Use a stomach protectant such as cytotech for older conventional NSAIDs. The newer Cox-2 are designed for stomach protection.
 
Do not accept arthritis as a diagnosis, since there are over 100 different types of arthritis with various symptoms,outcomes and different therapies.As one rhuematoligist said "if it talks like a duck,its a duck".
 
Persistence,despite ongoing disease is essential to limiting the damage and possible disability of RA when it is not controlled. Unfortunately the terms used to characterize RA are confusing. Terms such as early, late, chronic prolonged,active,intercurrent, or end-stage are only some of these.
 
These terms may do not suggest treatment can help. Some patients may consider it hopeless, but RA can be controlled.
 
The term "progressive",however, means that further treatment is necessary and persistence in treatment is beneficial,and essential.
 
Often,extra-articular effects appear later on in the course of the disease when the disease is still,not under control.Once the disease is controlled EAFs will not appear.
 
A specialist- rheumatoligist said at the large medical centre in which he works,wheel chair RA patients are rare. He also said in the past it was not the case.

The progress of rheumatoid arthritis is unpredictable,but effective treatment does help slow the deterioration. In a minority of cases there is total remission.
 
One third of all patient have the mild form of RA and in this group are patients who do not have the erosive,on-going type of disease seen in others. Treatment and effects are totally different,up to a point.
 
The prgnosis is more then likely poorer if rheumatoid factor (RF) is present from the beginning;if there are rheumatoid nodules;and/or if the patient is over 60 when the disease first appears. However,the type of onset (sudden,gradual,gout-like or non-joint) is not an indicator of how the disease will progress.
 
Early studies done in England had a gloomy outlook for the future of RA patients,but many factors contributed to the earlier datas,which should not occur today.
 
 In the old days,doctors waited to see the effects before aggresive therapy was instituted. Now doctors are more aggressive at onset. The high reported mortality rate had nothing to do with the rheumatoid disease.
 
Two recent studies point to a more optimistic outlook One from Finland, reported on 103 patients who had the disease for an average of 18 years. 1) 2.3 pwecent had completely normal function 2) only 6 out of 103 could be considered very seriously disabled 3) 20 % had total joint replacement of knees or hips
 
Another Canadian study looked at a group of 128 RA patients over a somewhat shorter period-6.5 years on average.
 
1) 42 % of patients had experienced RA continueously.
 
2) 40 % had arthritis that came and went.
 
3) 18 % had experienced only one attack.
 
Despite the fact that 80 % still had some ongoing difficulty,a third had no joint swelling; a quarter had no evidence of damage showing up on X-rays; and almost a third were functioning normally.
 
As we get more educated about the disease-things don't look that bad as some early reports indicated. In the reported deaths in the first English study, many deaths were not even caused by RA-yet they were included in the report as due to RA. 
 
The reported deaths in the old study did not investigate the reason for the rather high mortality report -yet the deaths were recorded !
 
Further investigation revealed the study was done on a group mainly composed of elderly patients,who had the more severe type of disease and who had other disease complications.
 
England has a high standard for medicine,but like anything else in the world,this highly publicized report had severe flaws

TNF-alpha And Cytokines:
 
Cytokines are a group of proteins that regulate the immune system's activity. In general cytokines can either stimulate or stifle the immune response.
 
Two important cytokines,Tumour Necrosis Factor (TNF)-alpha and Interleukin-1 (IL-1),help orchestrate the active phases of RA.
 
These cytokines are found in excess in the joints of  RA patients. Research aimed at inhibiting the activity of these cytokines has resulted in a number of new drugs for RA treatment.
 
TNF-alpha plays a central role in initiating events that lead to inflammation and destruction of joints. It stimulates the production of molecules necessary to attract white blood cells to joint spaces. It also stimulates the release of other enzymes with the ability to breakdown components of the joint (like collagen, cartilage,and bone).
 
Inhibiting the ability of TNF-alpha to initiate these events could dampen the destructive processes in RA. Many TNF-alpha inhibitors are in development. Recently,the FDA approved two TNF-alpha inhibitors. These inhibitors block TNF activity by blocking production of TNF or by preventing TNF from binding to its receptor.
 
Interleukin-1 (IL-1),activates several inflammatory cells and stimulates those cells to release other pro-inflammatory substances. Several IL-1 inhibitors designed to block Il-1's pro-inflammatory effects have shown promise in animal studies. Recently,the FDA aprroved Kineret.
 
These inhibitors block IL-1 activity by one of three main mechanisms: by preventing Il-1 from binding to its receptor,by blocking production of IL-1 or by blocking intracellular signaling once IL-1 has bound to its receptor.
 
(Scientists say inflammatory cells "talk-to-each-other",or signal-each-other in the inflammatory orchestration.)
 
A Cost Effectiveness Analysis of Treatment Options for Methotrexate-Naive Rheumatoid Arthritis: New treatment options for patients with MTX-naive RA have become available. Given wide variability in efficacy and cost among different treatment options,researchers sought to determine their relative cost effectiveness to help guide policy in different cost sonstrained settings.
 
Investigators performed a cost effectiveness analysis comparing 5 monotherapy options for patients with MTX-naive RA:
 
1) Etanercept.
 
2) Leflunomide.
 
3) MTX (up to 15 mg/weekly),4) sulfasalzine (SSZ).
 
5) No second line agent. A decision analysis model was used with a time horizon of 6 months.
 
They employed 2 measures of effectiveness based on published clinical trial data: American College of Rheumatology (ACR) 20 % response proportion (ACR 20) and a weighed average of proprtions achieving ACR 70,ACR 50 and ACR 20 (ACR 70 weighted response,ACR 70WR).
 
Incremental cost effectiveness ratios were calculated as additional cost per patient achieving either outcome,compared with the next most expensive option.
 
In both base case analyses employing ACR 20 and ACR 70WR as effectiveness measures;
 
MTX and SSZ both cost less were more effective (i.e. cost saving) than no second line agent.
 
Leflunomide cost more and was efficacious than SSZ (dominated) in analyses using either outcome.
 
The most efficacious option,etanercept,cost US $41,900 per ACR 20 and $40,800 per ACR 70WR compared with SSZ and MTX respectively. When researchers included only direct cost in analyses,the least expensive non-dominated option was SSZ with incremental cost effectiveness ratios of US $900 per ACR 20 and $1500 per ACR 70WR compared with no second line agent.
 
Overall, relative cost effectiveness between MTX and SSZ was sensitive to variation in relevant variables in sensitivity analyses. Otherwise,the investigator's  extensive sensitivity analyses did not substantially affect the base case results.
 
MTX is cost effective (cost saving vs the no second line agent option) for MTX-naive RA in achieving ACR 20 or ACR 70WR over a 6 month period.
 
 Based on available data,the relative cost effectiveness between SSZ and MTX cannot be determined with reasonable certainty and SSz therapy appear be as cost effective as MTX (cost saving) in achieving ACR outcomes over a 6 month period.
 
The most efficacious option,etanercept,incurs much higher incremental costs per ACR 20 or ACR 70WR than other options analyzed. Whether etanercept compared with MTX is cost effective depends on whether > $40,000 per ACR 20 or ACR 70WR over a six month period is considered acceptable.