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New 4-Year Data Show Genentech’s Enspryng (satralizumab-mwge) Significantly Reduces Debilitating Relapses in People With Neuromyelitis Optica Spectrum Disorder

– New data demonstrate Enspryng’s robust and sustained longer-term efficacy in preventing relapses in people with neuromyelitis optica spectrum disorder (NMOSD) –

– More than 70% of people treated with Enspryng remained relapse-free after 4 years in the SAkuraStar (73%) and SAkuraSky (71%) open-label extension (OLE) studies, with a favorable safety profile –

– Enspryng is now approved in 58 countries, including the United States, Canada, Japan, South Korea and the European Union

Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), today announced new longer-term efficacy and safety data for Enspryng (satralizumab-mwge). The data show Enspryng has a favorable benefit-risk profile and is effective in reducing relapses over four years of treatment in people with anti-aquaporin-4 antibody (AQP4-IgG) seropositive NMOSD, a rare debilitating disease that affects the central nervous system. Efficacy and safety results from the open-label extension (OLE) periods of the SAkuraStar and SAkuraSky studies, in addition to the design of SAkuraBONSAI, a new study in people with AQP4-IgG seropositive NMOSD who are treatment-naïve, or where prior rituximab (or biosimilar) treatment has failed, will be presented at the 37th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS).

“The positive longer-term efficacy and safety results for Enspryng are important for physicians as they consider Enspryng as a treatment option for their patients,” said Dr. Ingo Kleiter, Ruhr University Bochum, Germany. “Just one NMOSD relapse can lead to lifelong disability. An early accurate diagnosis followed by an effective treatment is vital to conserving the quality of life of people with this chronic disease.”

The pivotal SAkuraStar and SAkuraSky four year OLE data found that 73% and 71% of people with AQP4-IgG seropositive NMOSD treated with Enspryng remained relapse-free after 192 weeks (3.7 years), respectively, and 90% and 91% remained free from severe relapse.1 These results demonstrate that the robust efficacy observed in the studies’ double-blind periods is sustained longer-term for Enspryng as both a monotherapy and in combination with immunosuppressive therapy.

The data also demonstrate a favorable safety and tolerability profile for Enspryng in the overall Enspryng treatment period of up to seven years, comparable to the double-blind treatment periods in both SAkuraStar and SAkuraSky studies. Rates of adverse events and serious adverse events during the overall treatment periods were consistent with Enspryng and placebo in the double-blind periods. The most common adverse reactions observed were: headache, arthralgia, white blood cell count decrease, hyperlipidemia, and injection-related reactions. No new safety signals were observed.

“We are pleased that these longer-term data further reinforce the previously observed efficacy and safety of Enspryng, which was specifically designed for this lifelong, chronic disease by targeting the IL-6 pathway to reduce the frequency of relapses,” said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. “Enspryng is the only treatment for NMOSD that can be administered subcutaneously at home and has now been approved in over 50 countries. The totality of data, combined with the experience of people treated and their physicians, underscores the importance of this treatment option.”

Genentech is also initiating SAkuraBONSAI, a multicenter, Phase IIIb, international study, to further evaluate disease activity and progression using comprehensive imaging, biomarker and clinical assessments in NMOSD populations where further research is warranted. People with AQP4-IgG seropositive NMOSD, who are treatment-naïve or where prior rituximab (or biosimilar) treatment has failed, will be administered Enspryng monotherapy for two years and evaluated using clinical measures such as magnetic resonance imaging, optical coherence tomography and biomarkers of blood and cerebrospinal fluid.

Enspryng is the first and only NMOSD treatment administered subcutaneously every four weeks for adults living with AQP4-IgG seropositive NMOSD, allowing for home-dosing and increasing flexibility and convenience for people with NMOSD. Enspryng is approved in 58 countries, including the United States, Canada, Japan, South Korea and the European Union and applications are under review in additional countries.

About SAkuraStar and SAkuraSky in NMOSD

Enspryng has been investigated in two pivotal Phase III studies in neuromyelitis optica spectrum disorder (NMOSD), with the primary endpoint of both studies being time to first protocol-defined relapse (PDR) adjudicated by an independent review committee in the double-blind period. In the open-label extension (OLE) periods of the SAkura studies, PDRs were determined by the investigator.

The Phase III SAkuraStar study evaluated the efficacy and safety of Enspryng monotherapy administered to adults with NMOSD. In the anti-aquaporin-4 antibody (AQP4-IgG) seropositive subgroup, 83% treated with Enspryng remained relapse-free at 48 weeks, compared with 55% of those treated with placebo. At 96 weeks, 77% of those treated with Enspryng remained relapse-free, compared with 41% with placebo.

The Phase III SAkuraSky study evaluated the efficacy and safety of Enspryng in combination with baseline immunosuppressive therapy in adults and adolescents with NMOSD. Overall, 92% of AQP4-IgG seropositive participants receiving Enspryng in combination with immunosuppressive therapy remained relapse-free at 48 and 96 weeks, compared with 60% and 53% with placebo, respectively.

Enspryng showed a favorable safety and tolerability profile in the Phase III studies. The most common adverse reactions observed were: headache, arthralgia, white blood cell count decrease, hyperlipidemia and injection-related reactions.

About neuromyelitis optica spectrum disorder (NMOSD)

NMOSD is a rare, lifelong and debilitating autoimmune condition of the central nervous system that primarily damages the optic nerve(s) and spinal cord, causing permanent blindness, muscle weakness and paralysis. People with NMOSD experience unpredictable, severe relapses directly causing cumulative, permanent, neurological damage and disability. In some cases, relapse can result in death. NMOSD affects over 10,000 people in Europe, up to 15,000 people in the U.S. and approximately 200,000 people worldwide. NMOSD can affect individuals of any age, race and gender, but is most common among women in their 30s and 40s, and appears to occur at higher rates in people of African or Asian background.

NMOSD is commonly associated with pathogenic antibodies (AQP4-IgG) that target and damage a specific cell type, called astrocytes, resulting in inflammatory lesions of the optic nerve(s), spinal cord and brain. AQP4-IgG antibodies are detectable in the blood serum of around 70-80% of people with NMOSD.

Although most cases of NMOSD can be confirmed through diagnostic tests, people living with the condition are still frequently misdiagnosed with multiple sclerosis. This is due to overlapping characteristics of the two disorders, including a higher prevalence in women, similar symptoms and the fact that people can experience relapses in both conditions.

About Enspryng (satralizumab-mwge)

Enspryng, which was designed by Chugai, a member of the Roche Group, is a humanized monoclonal antibody that targets interleukin-6 (IL-6) receptor activity. The cytokine IL-6 is believed to be a key driver in NMOSD disease processes, triggering the inflammation cascade and leading to damage and disability. Enspryng was designed using novel recycling antibody technology. When compared to conventional antibodies, Enspryng’s recycling antibody technology enables the medicine to remain in the bloodstream for a longer period of time and bind repeatedly to its target (the IL-6 receptor) - maximally sustaining IL-6 suppression in a chronic disease like NMOSD and enabling subcutaneous dosing every four weeks.

Positive Phase III results for Enspryng, as both monotherapy and in combination with baseline immunosuppressive therapy, suggest that IL-6 inhibition is an effective therapeutic approach for NMOSD. The Phase III clinical development program for Enspryng includes two studies: SAkuraStar and SAkuraSky.

Enspryng is currently approved in 58 countries, including the United States, Canada, Japan, South Korea and the European Union.

Enspryng has been designated as an orphan drug in the United States, Europe, Japan and Russia. In addition, it was granted Breakthrough Therapy Designation for the treatment of NMOSD by the U.S. Food and Drug Administration (FDA) in December 2018, which is given to treatments that may demonstrate substantial improvement over other available options.

Indications and Important Safety Information

Patients should not take Enspryng if they:

  • are allergic to satralizumab-mwge or any of the ingredients in Enspryng
  • have an active hepatitis B infection
  • have active or untreated inactive (latent) tuberculosis (TB)

Enspryng may cause serious side effects including:

  • Infections. Enspryng can increase risk of serious infections some of which can be life-threatening. Patients should speak with their healthcare provider if they are being treated for an infection and call right away if there are signs of an infection, with or without a fever, such as:
    • chills, feeling tired, muscle aches, cough that will not go away or a sore throat
    • skin redness, swelling, tenderness, pain or sores on the body
    • diarrhea, belly pain, or feeling sick
    • burning when urinating or urinating more often than usual
    • A healthcare provider will check for infection and treat it if needed before starting or continuing to take Enspryng
    • A healthcare provider should test for hepatitis and TB before initiating Enspryng
    • All required vaccinations should be completed before starting Enspryng. People using Enspryng should not be given ‘live’ or ‘live-attenuated’ vaccines. ‘Live’ or ‘live-attenuated’ vaccines should be given at least 4 weeks before a patient starts Enspryng. A healthcare provider may recommend that a patient receive a ‘non-live’ (inactivated) vaccine, such as some of the seasonal flu vaccines. If a patient plans to get a ‘non-live’ (inactivated) vaccine it should be given, whenever possible, at least 2 weeks before starting Enspryng
  • Increased liver enzymes. A healthcare provider should order blood tests to check patient liver enzymes before and while taking Enspryng. A healthcare provider will dictate how often these blood tests are needed. Patients should complete all follow-up blood tests as ordered by a healthcare provider. A healthcare provider may wait to start Enspryng if liver enzymes are increased
  • Low neutrophil count. Enspryng can cause a decrease in neutrophil counts in the blood. Neutrophils are white blood cells that help the body fight off bacterial infections. A healthcare provider should order blood tests to check neutrophil counts while a patient is taking Enspryng.
  • Serious allergic reactions that may be life-threatening have happened with other medicines like Enspryng. Patients should call their healthcare provider right away if they have any of these symptoms of an allergic reaction:
    • shortness of breath or trouble breathing
    • swelling of lips, face, or tongue
    • dizziness or feeling faint
    • moderate or severe stomach (abdominal) pain or vomiting
    • chest pain

Before taking Enspryng, patients should tell their healthcare provider about all of their medical conditions, including if they:

  • have or think they have an infection
  • have liver problems
  • have ever had hepatitis B or are a carrier of the hepatitis B virus
  • have had or have been in contact with someone with TB
  • have had a recent vaccination or are scheduled to receive any vaccination
  • are pregnant, think they might be pregnant, or plan to become pregnant. It is not known if Enspryng will harm one’s unborn baby
  • are breastfeeding or plan to breastfeed. It is not known if Enspryng passes into breast milk. Patients should speak with their healthcare provider about the best way to feed one’s baby while on treatment with Enspryng

Patients should tell their healthcare provider about all the medicines they take, including prescription and over-the-counter medicines, vitamins and herbal supplements.

The most common side effects of Enspryng include:

  • sore throat, runny nose (nasopharyngitis)
  • headache
  • upper respiratory tract infection
  • rash
  • fatigue
  • nausea
  • extremity pain
  • inflammation of the stomach lining
  • joint pain

For more information about the risk and benefit profile of Enspryng, patients should ask their healthcare provider.

Patients may report side effects to the FDA at 1-800-FDA-1088 or Patients may also report side effects to Genentech at 1-888-835-2555.

Please see the full Prescribing Information for additional Important Safety Information.

About Genentech in neuroscience

Neuroscience is a major focus of research and development at Genentech and Roche. Our goal is to pursue groundbreaking science to develop new treatments that help improve the lives of people with chronic and potentially devastating diseases.

Genentech and Roche are investigating more than a dozen medicines for neurological disorders, including multiple sclerosis, stroke, Alzheimer’s disease, Parkinson’s disease and autism spectrum disorder. Together with our partners, we are committed to pushing the boundaries of scientific understanding to solve some of the most difficult challenges in neuroscience today.

About Genentech

Founded more than 40 years ago, Genentech is a leading biotechnology company that discovers, develops, manufactures and commercializes medicines to treat patients with serious and life-threatening medical conditions. The company, a member of the Roche Group, has headquarters in South San Francisco, California. For additional information about the company, please visit



1 Relapse associated with low likelihood of recovery, resulting in permanent disability


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