Copaxone (glatiramer acetate) is a disease-modifying therapy marketed by Teva Pharmaceuticals and approved by the U.S. Food and Drug Administration (FDA) for the treatment of relapsing-remitting multiple sclerosis (RRMS). The medicine has been shown to reduce the number of relapses in multiple sclerosis (MS) patients. 

How Copaxone works

MS is a progressive neurodegenerative disorder in which the immune system mistakenly targets the myelin protein. Myelin is the main component of the protective sheath that insulates nerve fibers. This triggers inflammation and causes damage to the brain and spinal cord, leading to a wide range of symptoms.

Copaxone is a small synthetic protein, made to mimic a fragment of myelin. It consists of four amino acids, the building blocks of proteins, that are found in myelin.

The exact mechanism of how Copaxone reduces the frequency of relapses in RRMS is not known, but it is thought that the medicine modifies the immune response against myelin. For example, Copaxone may act to increase the immune system’s tolerance to myelin through repeated exposure, in a similar way to a vaccine.

Another mechanism could be that Copaxone may alter which immune cells are active; it may be able to induce a type of immune cells called suppressor T-cells that secrete anti-inflammatory proteins and prevent damage. Copaxone may also act to prevent the activation of T-cells that target and attack myelin.

While Copaxone can reduce the rate of relapses and slow the progression of MS, it cannot reverse or cure the disease.

Copaxone in clinical trials

Copaxone has been studied in several clinical trials.

The key clinical trial that led to Copaxone’s approval for marketing was a study called the Copolymer 1 Multiple Sclerosis Study, carried out in the 1990s. The randomized, double-blind, placebo-controlled Phase 3 trial enrolled 251 patients with RRMS who received either Copaxone or a placebo daily for two years.

The initial results, published in the journal Neurology, demonstrated that patients receiving Copaxone had a 29 percent reduction in their relapse rate compared to those who received placebo. Patients also were assessed in terms of their change on the expanded disability status scale, after two years of treatment compared to the start of the trial. On average, patients taking Copaxone had an improved score after two years, while the score of patients in the placebo group had worsened. The treatment was well-tolerated, with the most common side effect being a reaction at the injection site.

Following the end of the trial, patients were given the chance to continue treatment in an optional extension study. The results of this extension study showed that after one to 11 months of follow-up treatment, the benefits of Copaxone were maintained, and no long-term complications were observed.

A total of 208 patients of the original 251 opted to participate in this open-label extension study in which all of them received Copaxone. A final report of the trial and the extension, which spanned a total of about six years, was published in the journal Multiple Sclerosis. Copaxone continued to provide a sustained reduction in relapse rate and slowed worsening disability.

More recently, the effectiveness of Copaxone given at a higher dose, three times weekly instead of daily, was assessed in a randomized placebo-controlled Phase 3 trial (NCT01067521) called GALA. A total of 1,404 participants with RRMS were recruited worldwide to receive Copaxone or a placebo for one year. This also was followed by an open label extension study.

The results, published in the Annals of Neurology, confirmed that Copaxone reduced the number of relapses compared to placebo, by about 34 percent. The patients also were assessed by magnetic resonance imaging (MRI) to check for lesions, or areas of damage, in the brain. Copaxone was associated with a significant reduction in the number of lesions compared to the placebo.

Other information

Copaxone is administered as an injection under the skin. Common side effects include reactions at the injection site (such as itching, swelling, redness, pain, or bruising), anxiety, chest pain, shortness of breath, palpitations (pounding or irregular heartbeat), flushing, hives, and swollen lymph nodes. 

The FDA originally approved the therapy to treat RRMS in 1996, and in March 2009 expanded this to include clinically isolated syndrome. In 2014, the FDA approved the higher-dose of Copaxone taken three times a week as a prescription, following the results of the GALA trial.

Generic versions of Copaxone also are now available.


Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.


  1. Lorraine L says:

    I was a participant in a double blind, placebo controlled study undertaken at Albert Einstein Hospital in Bronx, NY from 1980-1985. Why aren’t the results of that study mentioned?
    After FDA approval, I was able to get the drug with funding through NORD. I always felt it made a big difference in frequency and severity of relapses. The side effects were minor in comparison to the benefits. Once the funding ended, the cost of Copaxone made it an impossibility for me to continue using it. Sadly, even the relatively new generic to too costly for the average person who does not have a prescription insurance plan.

  2. Michelle says:

    On February 15th 2016 after my 7th Copaxone injection I went into a full anaphylaxis reaction & literally almost died. Thankfully my son was home to call 911, had he not been I wouldn’t be here. I didn’t see that reaction listed anywhere on the side effect list. Did I miss it or is it in fact not listed?

    • Kristin says:

      You had an allergic reaction. This is a side effect of ANY medication. It can happen the first time you take a med, or the 10th.

  3. Eileen says:

    I’ve been taking Copaxone for about a week, on my fourth injection, I had a low grade fever, chills, muscle aches and vomiting. Is there a way to minimize this? My fifth shot is tonight and I’ve been eating very bland food today.

    • Thecia mccoy says:

      Hello, I am about to take my 4th shot tomorrow and I have been experiencing the same symptoms. Did they ever go away or get better for you?

      • Joao PGC says:

        Hey thecia, how you doing? i started treatment december 21. I had not have many side effects yet. I have Pain after injecting, and once (8th time) it gave me dizziness, which affected me for half an hour and stopped. I am also having headache but i am not sure if it is related to the medicine.
        Hope you are good!

  4. Pambh says:

    I am having site reactions on my tummy. Big hard lumps under the skin that are round and stick around for days and days. One bruised and the lump was black. Is there a way to prevent this?

  5. Andrew says:

    I am using Copaxone for close to 5 years now. Works very well for me. No condition worsening, etc. Then 40mg version came out, and I started injections 3 time a week. Works great as well. Only issue was – site rotation, because before it was one site (hand, butt, etc) per day. Now you have to rotate the days and sites every week. Good thing at the end – I found a few apps to help me with those issues 🙂
    The best so far – Injection Tracker & Reminder for iOS. So if you are in my boat with Copaxone 40mg – that might be a good one for you .

  6. Vicki says:

    I have a question. I was diagnosed with RRMS in 2001. I was started on Avonex injections that were stopped after 6 years due to not being effective. Then, I was placed on Tecfidera for 7 years. Now, my neurologist wants to place me on Copaxone. Is this a normal medical plan?

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