Top 10 myasthenia gravis stories of 2023

In 2023, Myasthenia Gravis News brought up-to-date coverage of the latest scientific research and developments in the treatment of myasthenia gravis (MG).

Here are the 10 most-read news stories of 2023, along with a brief description of what made them relevant for our readers. We look forward to continuing to serve as a resource for the MG community in the year to come.

No. 10 – Immunosuppressants may ease symptoms of ocular MG

Treatment of ocular MG varies from person to person, but it usually begins with cholinesterase inhibitors. Researchers in Japan found that corticosteroids or other immunosuppressants, which are medications that suppress the immune system, may ease symptoms of ocular MG when used alone or in combination with cholinesterase inhibitors.

The proportion of patients failing to respond to treatment was about eight times lower in those who received immunosuppressants compared with those not treated with immunosuppressants. Overall outcomes were good, but symptoms persisted in more than half of the patients, even after treatment. Despite the benefits of immunosuppressants, disease treatment remains complex.

No. 9 – Rystiggo available to adults with generalized MG in US

UCB’s Rystiggo (rozanolixizumab-noli) entered the U.S. market in July, one month after its approval. It is available by prescription for adults with generalized MG who have self-reactive antibodies against the acetylcholine receptor (AChR) or muscle-specific tyrosine kinase (MuSK), the two most common MG-causing antibodies. Given by subcutaneous (under-the-skin) injection, Rystiggo eases symptoms of generalized MG, which causes muscle weakness in different parts of the body.

Patients prescribed Rystiggo (or their caregivers) can enroll in UCB’s ONWARD, a program that provides personalized support, including help in understanding insurance coverage and financial options, tools to track symptoms, and guidance with starting and continuing treatment.

No. 8 – MG with very late onset may have a poor prognosis

People who develop MG later in life, when they are 65 or older, may progress faster in the disease or be more likely to die than those who have an earlier onset of MG. The outlook may be even worse for those who have not been started on immunosuppressants.

Researchers in China stressed the importance of understanding how age affects the course of MG, and how doctors can best tailor disease treatment to each patient’s individual needs.

No. 7 – Plasma exchange may work better if certain white blood cells taken out

Plasma exchange, or plasmapheresis, may work better for severe MG when used in combination with a procedure to remove white blood cells known as lymphocytes from the blood. Plasma exchange is a procedure that clears disease-causing antibodies from the bloodstream.

The combined procedure, called lymphoplasmapheresis, resulted in similar or even better treatment outcomes compared with plasma exchange alone, and with fewer treatment rounds. Both successfully eased MG symptoms, but lymphoplasmapheresis appeared to perform better.

No. 6 – Anesthesia agents may be used without muscle relaxants during surgery

Researchers in Vietnam found both propofol and sevoflurane safe and effective in maintaining anesthesia when used without muscle relaxants in adults with mild MG symptoms undergoing thymus removal surgery. Problems with this gland may contribute to the production of MG-causing antibodies.

For some patients, muscle relaxants often used during surgery cause a serious worsening of MG symptoms that quickly can become life-threatening. The scientists noted that more research is needed to understand if propofol and sevoflurane are equally safe and effective in people with more severe disease.

No. 5 – Math tool may predict risk of conversion to generalized MG

Researchers in China developed a mathematical tool called a nomogram to estimate the likelihood of someone with ocular MG developing generalized MG within up to two years. The nomogram combines factors such as age at disease onset, sex, and the presence of a tumor in the thymus or self-reactive antibodies to accurately predict conversion to generalized MG.

People who tested positive for antibodies against the AChR or had another co-occurring autoimmune disease were around 55% more likely to see their ocular MG turn into the more generalized disease form.

No. 4 – Breathing test may tell when respiratory symptoms worsen

A noninvasive, low-cost single-breath count test may be used to check how well people with MG are breathing and whether their respiratory disease symptoms have worsened. The single-breath count test involves taking a deep breath and then counting at two counts per second in a normal voice, until another breath needs to be taken.

According to a review of eight studies, if an MG patient could count to 25 or more in English or Spanish before needing to take another breath, their respiratory function was likely to be normal. It is not known if this cutoff value would change if counting were done in other languages.

No. 3 – Sanofi drops clinical development of tolebrutinib for MG

Sanofi announced in February that it was stopping the clinical development of tolebrutinib, its oral Bruton’s tyrosine kinase (BTK) inhibitor for the treatment of MG. The decision was taken for strategic reasons in light of the disease’s “emerging competitive treatment landscape,” the company announced.

As a result, Sanofi began closing URSA (NCT05132569), a global Phase 3 clinical trial into the safety and efficacy of tolebrutinib versus a placebo in adults with moderate-to-severe generalized MG.

No. 2 – FDA approves Rystiggo for generalized MG

In June, the U.S. Food and Drug Administration approved UCB’s Rystiggo for use by adults with generalized MG who have antibodies against the AChR or MuSK. The decision made Rystiggo the first medication approved in the U.S. for MG caused by either of these two types of self-reactive antibodies.

Rystiggo works by speeding the breakdown of self-reactive antibodies within the bloodstream. With fewer harmful antibodies, it is expected that MG symptoms will ease.

No. 1 – Woman’s myasthenic crisis follows anesthesia for MRI

A 69-year-old woman in Portugal developed a myasthenic crisis after undergoing general anesthesia with propofol and sevoflurane. She had asked for anesthesia before a planned abdominal MRI due to claustrophobia, but she omitted to inform doctors of her MG diagnosis.

Weakened breathing muscles can place people with MG at risk of a myasthenic crisis, or severe breathing problems that require hospitalization. In the case of this woman, early detection and treatment of the myasthenic crisis avoided potentially life-threatening complications.

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We look forward to continuing to bring you the latest news about MG in 2024, and we wish all a very happy new year!