What Is Therapeutic Plasma Exchange (TPE)?

Therapeutic plasma exchange (TPE), also known as plasmapheresis and apheresis, is a procedure in which the plasma in your blood is removed and replaced with another fluid, similar to what happens in kidney dialysis. It's sometimes used as a therapy in several types of neurological diseases, including multiple sclerosis (MS). TPE is a fairly painless procedure and serious side effects are rare.

Therapeutic plasma exchange is recommended by the American Society for Apheresis (ASFA) as a second-line treatment for MS when you're having an acute relapse that's not responding to the go-to therapy of corticosteroids (like Solu-Medrol). It's also sometimes used for people who are unable to receive high doses of corticosteroids.

TPE is not currently recommended by the ASFA to treat primary or secondary progressive multiple sclerosis, as there isn't enough evidence that it's effective for this purpose. However, the organization's guidelines do acknowledge that more research may show it to be a beneficial long-term therapy for chronic progressive MS.

On March 24, the FDA announced an investigational treatment for the new coronavirus, COVID-19, using therapeutic plasma exchange. Working under the assumption that people who have recovered from COVID-19 now have antibodies to the SARS-Cov-2 virus in their blood, researchers are interested in using those antibodies as a treatment for those who are sick. 

In clinical trials, antibody-rich plasma will be collected from blood samples of recovered COVID-19 patients and transferred to critically ill COVID-19 patients. Mount Sinai Health System in New York City will be the first in the U.S. to experiment with therapeutic plasma exchange for this purpose.

The FDA is allowing any healthcare provider treating serious cases of COVID-19 to use single-patient emergency Investigational New Drug Applications (eINDs) to request plasma for their patients. 

During TPE, a machine removes your blood and then separates the plasma, the liquid portion of blood, from your red and white blood cells. The plasma is then discarded and replaced with a different type of fluid, usually donor plasma and/or albumin solution, before being returned along with the cells back to your body.

Scientists believe that removing these antibodies during a relapse could limit the duration of the relapse and the damage caused by inflammation. However, once these antibodies are sequestered or deposited in the lesions that occur with MS, plasma exchange can no longer remove them and it will probably not have any treatment benefit.

This is why early treatment results in better outcomes.

The treatment guidelines from the ASFA, which include extensive literature reviews, report that five to seven TPE treatments benefit approximately 50 percent of patients with an MS relapse that doesn't respond to steroid treatment. The researchers also found that the earlier patients were treated, ideally within 14 to 20 days of their symptoms first appearing, the better their outcome was.

One 2017 study looked at 37 patients who were treated with TPE because their MS relapses had been unresponsive to corticosteroids. The researchers wanted to see if the TPE treatment helped these patients again become responsive to corticosteroids, so during the first relapse the patients had post-TPE, they were all treated with steroids once again.

With the steroid treatment, 10 of the patients showed marked improvement, 24 showed moderate improvement, and there was no effect in three. The researchers concluded that corticosteroids might still be the first-line therapy in subsequent relapses after TPE.

Another 2016 study looked at TPE for 36 patients with either secondary progressive or active primary progressive MS that hadn't responded well or at all to steroid treatment for relapse. They were all treated with five courses of TPE within a span of two weeks, followed by one TPE treatment per month for the next year.

Half of the patients (18) had a significant improvement in their Expanded Disability Status Scale (EDSS) a year after TPE, while 16 remained stable, and two deteriorated further. Prior to TPE, 16 patients with active primary progressive MS had reported a total of 16 relapses the year before. A year after TPE, the total number of relapses decreased to two.

The study also found that the improvement rate was greater in patients with active primary progressive MS (71 percent) than in those with secondary progressive MS (43 percent). These results indicate that TPE may indeed be a beneficial second-line option for some patients with progressive MS who don't respond to steroids.

During TPE, needles are placed in both of your arms, or sometimes into another location, like your neck, if the veins in your arm can't be accessed. Blood is then drawn out of your body through the needle in one arm, where it goes through a tube into a blood cell separator, a centrifuge that isolates the plasma from the red and white blood cells.

The cellular components are combined with the donor plasma and/or albumin solution and a short-acting anticoagulant, usually citrate, is added to prevent clotting. The replacement fluid is then delivered to you through the needle in your other arm.

All of these steps happen automatically and continuously through IV-type needles/catheters. In some cases, this is done through one needle and the separation and remixing are done in small batches. Regardless, the whole procedure takes between two and four hours to complete.

Side effects and complications depend on a number of factors such as your general health, the number of TPE procedures you have, and the type of replacement fluid that's used.

Side effects of TPE are more common when donor plasma is used as the replacement fluid.

Serious complications from TPE are not very common. The most dramatic of these is anaphylaxis, which is usually caused by a severe allergic reaction to the plasma replacement fluid. This is one of the reasons why plasma exchange is done within a monitored setting.

Infections from TPE are a potential risk, but also rare, thanks to new technology and sterile replacement fluid.

Blood clots are another rare serious complication, so your doctor may prescribe a blood thinner called an anticoagulant before your procedure to reduce this risk. Examples include Coumadin (warfarin), Pradaxa (dabigatran), Xarelto (rivaroxaban), Eliquis (apixaban), and Savaysa (edoxaban).

Other potential risks of TPE include:

• Bleeding
• Irregular heart rhythm
• Shortness of breath
• Abdominal cramps
• Tingling in the limbs
• Seizures

Very rarely, TPE can lead to death, but this occurs in only 0.03 percent to 0.05 percent of cases. The majority of deaths result from respiratory or cardiac complications.

Prices vary for TPE depending on where you live, where you have it done, and whether or not your insurance covers the procedure, but are somewhere in the ballpark of $1200 per procedure when albumin is the replacement fluid that's used.

If your doctor deems it necessary for you to have TPE, your insurance will likely cover it, though you may need pre-approval or a letter from your doctor. Contact your insurance provider for more information.

TPE is generally a safe and well-tolerated procedure, so it may be a good approach if you're having a relapse that's not responding to corticosteroids. More research needs to be done on the effects of TPE on progressive MS and as a long-term treatment for MS. Be sure to talk to your doctor about any concerns or questions you may have regarding all of your treatment options and whether TPE might be an appropriate choice for you. You can use our Doctor Discussion Guide below to help you start that conversation.