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Genentech Provides Update on Tominersen Program in Manifest Huntington's Disease

– Dosing to stop in Phase III clinical study of tominersen following recommendation from an Independent Data Monitoring Committee (iDMC) –

– No new safety signals were identified for tominersen in the iDMC’s review –

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), announced today the decision to discontinue dosing in the Phase III GENERATION HD1 study of tominersen in manifest Huntington’s disease (HD). The decision was based on the results of a pre-planned review of the data from the Phase III study conducted by an unblinded Independent Data Monitoring Committee (iDMC). The iDMC made its recommendation based on the investigational therapy’s potential benefit/risk profile for study participants. No new or emerging safety signals were identified for tominersen in the review of the data from this study. Genentech intends to continue following participants for safety and clinical outcomes, without the dosing of the investigational medicine or placebo. Once full data from the Phase III study are available and analyzed, Genentech will share learnings and future plans with the HD community.

Dosing will be paused in the open-label extension study (GEN-EXTEND) of tominersen while data are carefully analyzed to inform next steps on this study.

“This is very unfortunate news to deliver on the tominersen Phase III study and we know it will be especially difficult for people with Huntington’s disease to hear. The HD community currently has no treatments to stop or slow the progression of this rare neurodegenerative disease that impacts families across generations,” said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. “GENERATION HD1 is the largest clinical trial in Huntington’s disease to date and we do know that the data generated will significantly advance our understanding of huntingtin-lowering as a potential treatment approach. We would like to thank all of the individuals and families participating in the study for their contribution, as well as the broader HD community for their commitment and collaboration.”

The Phase I PK/PD study (GEN-PEAK) of tominersen and the observational Genentech and Roche HD Natural History Study will continue.

About tominersen and the clinical trials
Tominersen, previously IONIS-HTTRx or RG6042, is an investigational antisense therapy designed to reduce the production of all forms of the huntingtin protein (HTT), including its mutated variant, mHTT. In December 2017, Roche licensed the investigational molecule from Ionis Pharmaceuticals.

Tominersen is being investigated in HD in the following clinical studies:

  • GENERATION HD1: a randomized, multicenter, double-blind, placebo-controlled Phase III clinical study evaluating the efficacy and safety of treatment with tominersen in people with manifest HD over 25 months. Study participants were randomized to either 120 mg every 2 months or 120 mg every 4 months intrathecal injections of tominersen, or placebo. The study has recruited 791 participants from 18 countries around the world.
  • GEN-EXTEND: an open label extension study for participants coming from any Genentech and Roche HD study. Participants receive 120 mg tominersen every 2 months or every 4 months in the study.
  • GEN-PEAK: a Phase I study aiming to better understand the pharmacokinetics of tominersen and how tominersen affects mHTT levels and other markers in the spinal fluid and blood, which studies a range of doses from 30 mg to 120 mg of tominersen over two administrations.

About Huntington’s disease
Huntington’s disease is a rare genetic, progressive condition that causes the nerve cells in the brain to break down, causing problems with a person’s ability to think, move and function, leading to increasing disability and loss of independence. It has a devastating impact on people living with the disease, and the hereditary nature of HD means it profoundly affects entire families for generations. Survival ranges from approximately 10-20 years following motor onset of the disease. There is no known cure for HD and no approved therapies that treat the underlying cause.

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, Huntington’s disease, Parkinson’s disease, Duchenne muscular dystrophy 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 http://www.gene.com.

Contacts

Media Contact: Liz Tomaino (650) 467-6800
Advocacy Contact: J.P. Sacksteder (650) 666 7329
Investor Contacts: Lisa Tuomi (650) 467-8737
Karl Mahler 011 41 61 687 8503

Genentech

OTCQX:RHHBY

Release Versions

Contacts

Media Contact: Liz Tomaino (650) 467-6800
Advocacy Contact: J.P. Sacksteder (650) 666 7329
Investor Contacts: Lisa Tuomi (650) 467-8737
Karl Mahler 011 41 61 687 8503

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