November 6, 2019 / Clinical Trials

Roche/Genentech Announces Decision to Discontinue Development of RG6206 (RO7239361)

We are disappointed to learn that Roche/Genentech is discontinuing development of their investigational anti-myostatin adnectin RG6206 (RO7239361) for the treatment of Duchenne. According to the company, this decision was based on results from a pre-planned futility analysis of the Phase IIb/III SPITFIRE study (WN40227), which indicated that RG6206 (RO7239361) was highly unlikely to meet its primary endpoint. From a safety perspective, no new safety signals were detected as part of this analysis.

Our hearts and gratitude go out to the brave young men who participated in this trial and their families who supported them every step of the way. The failure of a trial is always a blow to our community, but we remain hopeful that the forthcoming data from this trial will inform other potential treatments and that these experiences will lead us to the day that we end Duchenne.

Roche/Genentech has spent the last 24 hours notifying investigators so that they can tell the families who participated and Roche/Genentech will be hosting a community webinar on Friday, November 8 at 11 am eastern to discuss the results of their trial and the basis for their decision. Data will then be shared with the community at an upcoming conference (place & time to be determined).

Read Roche/Genentech’s letter to the community:

6 November 2019

Dear members of the Duchenne community,

We are writing to share with you unfortunate news about our clinical development program studying RG6206 (RO7239361), an investigational anti-myostatin adnectin protein, in ambulatory boys with Duchenne Muscular Dystrophy (DMD).

We are disappointed to announce that the clinical development program studying RG6206 (RO7239361) in Duchenne will be discontinued. This concerns both RG6206 studies: the open-label extension study of the Phase Ib/II THUNDERJET study, evaluating the safety and tolerability of RG6206 in ambulatory boys with DMD; and the Phase II/III SPITFIRE study, evaluating the efficacy, safety and tolerability of RG6206 in ambulatory boys with DMD. Our decision to close this program was made based on the results of a pre-planned interim data analysis of the Phase II/III SPITFIRE study, which indicated that RG6206 was highly unlikely to demonstrate clinical benefit as defined by meeting the primary endpoint (change from baseline in the North Star Ambulatory Assessment (NSAA) total score versus placebo). As you know, NSAA is a 17-item rating scale that is used to measure functional motor abilities in ambulant children with DMD. It was used to assess the treatment effects with RG6206 in the Phase II/III SPITFIRE study. No safety signals were observed in this analysis and the overall safety profile was similar to that seen in previous trials.

We have notified all the clinical trial sites and the investigators are now in the process of informing the study participants and families. Since SPITFIRE is a global trial with clinical sites in several countries, spanning many time zones, this may take some time and we acknowledge that members of the community might find out at different times and in different ways. It is our intention to provide as much information as we can to the community. To that end, we will be holding two global community webexes to accommodate different time zones on Friday the 8th of November, at 7:00 am GMT and 4:00 pm GMT/11:00 am EST. The link to participate in either WebEx is:

We recognise this news is deeply disappointing for the Duchenne community, especially in view of the historical challenges in DMD drug development and the ongoing need for new treatment options to treat this devastating disease. While the science and large body of research gave us hope that RG6206 would have offered people living with DMD and their families a safe and effective treatment option, the results of the SPITFIRE study at this time lead us to the difficult conclusion that this approach will not be successful.

We thank the community for supporting our efforts to develop RG6206 and are especially grateful to the individuals and families who participated in our clinical studies for RG6206. We sincerely thank you for your time, your partnership and your unwavering commitment to research.

Data from the Phase II/III SPITFIRE study interim analysis will be presented at upcoming congresses and additional data about RG6206 will be shared with the scientific and patient communities over the coming months in order to contribute to the broader community’s efforts to develop new treatment options for people with this condition.

Roche and Genentech will also continue to partner with the global Duchenne community on ongoing projects, including with World Duchenne Organization on its Psychosocial Programme, as well as its data sharing initiative. We will also be sharing our data for RG6206 with other consortia, for example, the collaborative Trajectory Analysis Project (cTAP) consortium.

Again, we are saddened to have to announce this decision and we share the community’s disappointment.

  • If you are a study participant or family member, we encourage you to reach out to your study physician for more information and detailed next steps.
  • For more information or questions about the study or study sites, you can also reach out to us via e-mail at or by phone at +1 888 662 6728.


Eydith Comenencia Ortiz and Elena Zhuravleva, on behalf of the Roche and Genentech Global Duchenne Team

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