Understanding Aubagio and Its Role in Multiple Sclerosis Treatment
Multiple sclerosis (MS) is a chronic neurological condition that affects nearly one million people in the United States [1.9.2]. The disease causes the immune system to mistakenly attack the protective sheath (myelin) that covers nerve fibers, leading to communication problems between the brain and the rest of the body. Aubagio, the brand name for the drug teriflunomide, is a disease-modifying therapy (DMT) prescribed to manage this condition [1.2.4].
Specifically, Aubagio is FDA-approved for treating relapsing forms of MS in adults, which include [1.2.1, 1.2.3]:
- Clinically Isolated Syndrome (CIS): The first episode of neurologic symptoms that lasts at least 24 hours.
- Relapsing-Remitting MS (RRMS): The most common form, characterized by clear relapses of new or increasing neurologic symptoms, followed by periods of partial or complete recovery.
- Active Secondary Progressive MS (SPMS): A stage where disability steadily worsens, but there are still occasional relapses or new MRI activity.
By taking this once-daily oral tablet, patients may experience a slower progression of the disabling effects of MS and a decrease in the number of relapses [1.2.1, 1.4.4]. Generic versions of Aubagio, under the name teriflunomide, became available in 2023 [1.11.1].
How Aubagio Works: The Mechanism of Action
While the exact way Aubagio works isn't fully understood, it is classified as a pyrimidine synthesis inhibitor [1.2.4, 1.3.4]. Its primary function involves blocking a specific mitochondrial enzyme called dihydroorotate dehydrogenase [1.3.1, 1.13.2].
Here's what that means for the body:
- Inhibiting Immune Cell Proliferation: Lymphocytes (T-cells and B-cells) are key players in the immune attack on myelin in MS. These cells divide rapidly and require large amounts of pyrimidines, which are essential building blocks for DNA and RNA [1.2.3, 1.3.1].
- Reducing Inflammation: By inhibiting pyrimidine synthesis, Aubagio limits the proliferation of these activated lymphocytes [1.3.3]. This action helps to calm the immune system and reduce the inflammation that damages nerves in the brain and spinal cord [1.2.4, 1.3.2].
Unlike some other treatments, Aubagio is a small-molecule drug made from chemicals in a lab, not a biologic derived from living sources [1.11.1]. It is considered an immunomodulatory agent with anti-inflammatory properties [1.3.2, 1.3.4].
Important Safety Information and Side Effects
Before starting Aubagio, healthcare providers will conduct several tests, including liver function tests, a complete blood count (CBC), a tuberculosis screening, and a blood pressure check [1.8.1]. This medication carries boxed warnings from the FDA, which are the most serious kind, for two major risks: severe liver injury (hepatotoxicity) and harm to an unborn baby (embryofetal toxicity) [1.6.2, 1.6.4].
Common side effects reported in clinical trials include [1.5.1, 1.5.4]:
- Headache
- Hair thinning or loss (alopecia)
- Diarrhea
- Nausea
- Increase in liver enzymes (ALT)
- Numbness or tingling in hands or feet (paresthesia)
Serious side effects can also occur and require immediate medical attention. These include signs of liver problems (jaundice, dark urine, abdominal pain), serious skin reactions like Stevens-Johnson syndrome, increased blood pressure, peripheral neuropathy, and an increased risk of infections [1.2.4, 1.5.2, 1.6.4]. Because Aubagio weakens the immune system, patients should not receive live vaccines while taking it [1.5.1].
Due to the risk of birth defects, Aubagio is contraindicated for pregnant women and women of reproductive potential not using effective contraception [1.6.3, 1.12.2]. The drug can remain in the body for up to two years after stopping treatment. A special "accelerated elimination procedure" using cholestyramine or activated charcoal can be used to clear the drug from the body more quickly if a patient wishes to become pregnant or experiences severe side effects [1.4.2, 1.11.1].
Aubagio Compared to Other MS Medications
Choosing an MS therapy is a complex decision made between a patient and their doctor. Aubagio is often compared to other oral DMTs.
| Feature | Aubagio (Teriflunomide) | Tecfidera (Dimethyl fumarate) | Gilenya (Fingolimod) | Copaxone (Glatiramer acetate) |
|---|---|---|---|---|
| Administration | Once-daily oral tablet [1.4.4] | Oral medication [1.2.3] | Once-daily oral medication [1.2.3] | Injectable medication [1.2.3] |
| Mechanism | Pyrimidine synthesis inhibitor; reduces lymphocyte proliferation [1.3.1]. | Believed to have anti-inflammatory and immunomodulatory effects [1.2.3]. | Traps certain immune cells in lymph nodes to prevent them from reaching the CNS [1.2.3]. | Synthetic protein resembling myelin; modifies the immune response [1.2.3]. |
| Key Consideration | Boxed warnings for liver damage and fetal harm [1.6.4]. Long half-life requires an elimination procedure if stopped quickly [1.11.1]. | --- | Requires monitoring for heart issues, especially at the first dose [1.7.1]. | --- |
| Efficacy Note | Reduces relapses by about 31% compared to placebo [1.13.2]. | Studies suggest it may be more effective than Aubagio at preventing relapses [1.7.3]. | Studies suggest it may be linked to lower relapse rates than Tecfidera or Aubagio [1.7.2, 1.7.4]. | --- |
Conclusion
Aubagio (teriflunomide) is an established oral, once-daily disease-modifying therapy for adults with relapsing forms of multiple sclerosis [1.2.1]. It works by modulating the immune system to reduce the frequency of relapses and slow the progression of physical disability [1.2.1, 1.13.2]. While it offers the convenience of an oral dose, patients and doctors must carefully consider its significant safety profile, including boxed warnings for liver damage and fetal harm, as well as common side effects like hair thinning and diarrhea [1.5.1, 1.6.4]. As with any MS treatment, the decision to use Aubagio should be individualized, weighing its benefits against its potential risks in consultation with a neurologist experienced in managing MS.
For more information from an authoritative source, you can visit the National Multiple Sclerosis Society.
