JAK Inhibitors for Rheumatoid Arthritis

Reviewed by Brunilda Nazario, MD on October 08, 2020

If you have rheumatoid arthritis (RA), your doctor may suggest Janus kinase (JAK) inhibitors to help ease your joint pain and swelling. These drugs tamp down your overactive immune system -- the body's defense against germs -- to help prevent damage to your joints.

JAK inhibitors belong to a family of medicine called DMARDs (disease-modifying antirheumatic drugs). Thre JAK inhibitors, baricitinib (Olumiant),tofacitinib (Xeljanz), and upadacitinib (Rinvoq), are approved by the FDA to treat rheumatoid arthritis. More should appear in the next few years if they succeed in clinical trials.

How JAK Inhibitors Work

If you have RA, your body makes too many proteins called cytokines, which play a role in inflammation. Some cytokines attach to receptors on immune cells, like a key fitting into a lock. When that happens, messages are sent to the cell to make even more cytokines.

JAK inhibitors put a wrench in the process by blocking the messaging pathway. This calms down your immune system and helps ease your RA symptoms.

Who Benefits?

You may be among the many people with RA whose symptoms are well-controlled with an older drug, such as adalimumab (Humira) or methotrexate (Trexall). In that case, you may not need a JAK inhibitor.

But the older drugs don't always work for everyone. About 65% of people who take DMARDs, for example, get relief from symptoms. If you're not in this group, a JAK inhibitor might make a difference. In one study, about half of people with RA who didn't improve with biologic drugs had symptoms that were less severe after they took the JAK inhibitor tofacitinib for 3 months.

Another advantage of JAK inhibitors is that you can take them by mouth. You must inject biologics, such as adalimumab, into your skin, while doctors infuse others into the bloodstream. But you can take JAK inhibitors as a pill.

Side Effects

Because JAK inhibitors put the brakes on some immune system actions, they can leave you open to different kinds of infections. In clinical trials, a handful of people who took tofacitinib came down with tuberculosis (TB), a serious bacterial lung disease. You may also be more likely to get common viral diseases, such as herpes zoster (shingles), when you take JAK inhibitors. But the drugs have a short "half-life," which means that if you stop taking them, your body will soon get back its full ability to fight infection.


JAK inhibitors can sometimes give you anemia due to the way they affect a protein in your body that's needed to make red blood cells. They can lower white blood cells counts as well.

How Biologics Can Help Your RAThese meds help a lot of people with their RA joint pain by targeting their immune system.123

SPEAKER: Biologics represent

a class of medications in which

we can target particular parts

of the immune system.

Using biologic therapy,

we can try and tailor

the treatment towards getting

a particular person's

rheumatoid arthritis

under better control.

There's no one-size-fits-all

type of an answer for rheumatoid


The decision about whether

or not to use a biological agent

to control the disease is really

a personal one.

The physician and the patient

will end up talking together

to decide whether the disease

manifestations are

aggressive enough in which they

need to use a biologic agent

or whether

a different medication might be


In general, biologics are

safe medications,

and we use them for a lot

of different patients.

However, just

like any other medication,

they have the potential for side


In patients that may have

certain types of infections

or certain exposure

of infections in the past,

they might not


suitable for that particular


In addition,

particular biologics

may interact with other parts

of the immune system

or other medications

that people are taking, and so

in those cases,

the decision as to whether

or not to use a biologic

and if so, which one,

is really

a customized, personalized


In general, the biologics work

for a large portion

of the population, especially

those that may not have

responded well enough

to the more traditional


Most biologics take a few weeks

in order for them to take

maximal effect,

but that varies a little bit

depending on which biologic

we're talking about.

We really, for the longest time,

had very limited treatments

in order to help keep

rheumatoid arthritis

under control.

With these biologic agents,

we've been able to make patients

feel better,

have longer, healthier lives

and be able to be more active.

And so I think that this is

a really exciting development

for both rheumatologists

as well as the patients which we

deal with.

I think that it's really

important to talk

with your physician

if you don't have good disease

control using other medications

and decide whether a biologic

might be right for you.

Prateek Gandiga, MD./delivery/79/22/79224dc7-da12-4ceb-bc03-8cfc8ccaa619/vd-1369-ra-how-biologics-help_,1000k,4500k,750k,2500k,400k,.mp412/20/2017 13:22:00650350test tubes/webmd/consumer_assets/site_images/article_thumbnails/video/generic_aidshiv_3_video/650x350_generic_aidshiv_3_video.jpg091e9c5e818a8b5d

The drugs may bump up your cholesterol numbers, but you can get around this side effect by taking a statin drug, such as atorvastatin (Lipitor), at the same time.

Some doctors are also worried that you may have higher odds of cancer if you take JAK inhibitors, because the drugs block immune system processes that prevent tumors. You may also have a greater chance of getting blood clots when you use these drugs.
Because these medications are fairly new, doctors are keeping tabs on their long-term safety. Check with your doctor to make sure these drugs don't cause any harm when you take them along with other medicines.

WebMD Medical Reference



European Medical Journal: "JAK Inhibitors in the Treatment Algorithm of Rheumatoid Arthritis: A Review."

Annals of the Rheumatic Diseases: "Janus Kinase Inhibitors in Autoimmune Diseases."

Expert Opinion on Pharmacotherapy: "Chemical JAK Inhibitors for the Treatment of Rheumatoid Arthritis."

European Respiratory Journal: "Cytokines and the Lung."

Journal of Inflammation: "Tyrosine Kinases in Rheumatoid Arthritis."

The New England Journal of Medicine: "Placebo-Controlled Trial of Tofacitinib Monotherapy in Rheumatoid Arthritis."

Rheumatic Disease Clinics of North America: "Biologics in Early Rheumatoid Arthritis."

Drug Safety: "Thromboembolism with Janus Kinase (JAK) Inhibitors for Rheumatoid Arthritis: How Real is the Risk?"

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