Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), announced today interim clinical data from the dose-finding parts of the pivotal FIREFISH and SUNFISH studies investigating risdiplam (RG7916) in spinal muscular atrophy (SMA). In the FIREFISH study in Type 1 SMA, six out of 14 infants (43 percent) were able to sit (with or without support), including three (21 percent) who achieved unassisted stable sitting after eight months of treatment. In addition, four infants (29 percent) demonstrated rolling to the side; seven (50 percent) kicking and six (43 percent) achieved upright head control. These milestones were assessed according to the Hammersmith Infant Neurological Examination (HINE) Module 2 and are key secondary endpoints in the confirmatory part of FIREFISH.
The data were presented at the 23rd International Annual Congress of the World Muscle Society in Mendoza, Argentina. Roche and Genentech are leading the clinical development of risdiplam, an oral SMN2 splicing modifier, as part of a collaboration with the SMA Foundation and PTC Therapeutics.
“We are highly encouraged by these data showing infants treated with risdiplam surviving and achieving developmental milestones beyond the natural history of this devastating disease,” said Sandra Horning, M.D., chief medical officer and head of Global Product Development. “SMA therapies that produce a sustained increase in SMN protein in both the CNS and periphery may provide comprehensive benefits to people diagnosed with SMA, and we look forward to sharing additional data on risdiplam as the clinical program progresses.”
Updated analyses of the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), a scale developed to assess motor function in infants with Type 1 SMA, demonstrated that eight out of 14 infants in FIREFISH (57 percent) achieved a score of 40 or above at their eight-month visit. Typically, an infant with Type 1 SMA does not demonstrate any motor improvement and can decline during this time period. The median CHOP-INTEND scores increased over time (37.5 at 6 months [n=20] compared to 41.5 at eight months [n=14]). The median age at first dose in FIREFISH was 6.7 months and median treatment duration was 9.5 months. Nineteen out of 21 infants enrolled (90 percent) remain alive with two having discontinued due to the fatal progression of their disease. Three patients are now over 24 months old. No infant has required a tracheostomy or permanent ventilation since study initiation, and no infant has lost the ability to swallow. The most common adverse events were fever (pyrexia; 52.4 percent), diarrhea (26.8 percent), upper respiratory tract infections (19 percent), ear infections (14.3 percent), pneumonia (14.3 percent), constipation (14.3 percent), vomiting (14.3 percent), cough (14.3 percent) and upper respiratory tract inflammation (14.3 percent).
In Part 1 of the SUNFISH study in Type 2 and 3 SMA, SMN protein median increases of greater than two-fold, as measured in blood, were seen after 12 months. A very broad patient population aged between two to 24 years was included, ranging in functional status from weak non-ambulant to strong ambulant, and with varying degrees of scoliosis from none to severe. Twenty-one patients initially received lower doses of risdiplam for at least 12 weeks. Of the patients treated with risdiplam for at least one year (n=30), the median change from baseline in Motor Function Measure (MFM), the primary endpoint in the confirmatory part of SUNFISH and a scale used to assess motor function in neuromuscular diseases, was a 3.1-point improvement. Sixty-three percent of patients experienced an improvement in MFM over baseline of three points or more after one year. Such improvements were seen both in patients under 12 years old (76 percent; n=17) and over 12 years old (46 percent; n=13). When considering patients who experienced any amount of improvement over baseline, the percentages were 70 percent overall, 76 percent for the younger age group, and 62 percent for the older patients. Serious adverse events that occurred in two or more of the 51 patients exposed to risdiplam were nausea (4 percent), upper respiratory tract infection (4 percent) and vomiting (4 percent). To date there have been no drug-related safety findings leading to withdrawal from any study.
Follow-up is ongoing for the confirmatory Part 2 portions of both the FIREFISH and SUNFISH studies.
Spinal muscular atrophy (SMA) is a severe, inherited, progressive neuromuscular disease that causes devastating muscle atrophy and disease-related complications. It is the most common genetic cause of infant mortality and one of the most common rare diseases, affecting approximately one in 11,000 babies. SMA leads to the progressive loss of nerve cells in the spinal cord that control muscle movement. Depending on the type of SMA, an individual’s physical strength and their ability to walk, eat or breathe can be significantly diminished or lost. SMA is caused by a mutation in the survival motor neuron 1 (SMN1) gene that results in a deficiency of SMN protein. SMN protein is found throughout the body and increasing evidence suggests SMA is a multi-system disorder and the loss of SMN protein may affect many tissues and cells throughout the body.
Risdiplam is an investigational, oral medicine that is systemically distributed and designed to increase SMN protein levels in the central nervous system (CNS) and throughout the body. It is designed to help the SMN2 gene produce more functional SMN protein, to better support motor neurons and muscle function. Roche and Genentech are leading the clinical development of risdiplam in collaboration with the SMA Foundation and PTC Therapeutics. Risdiplam is currently being evaluated in three multicenter trials in people with SMA:
- FIREFISH – an open-label trial in infants aged one to seven months with Type 1 SMA
- SUNFISH – a double-blind, placebo-controlled trial in children and young adults (two to 25 years old) with Type 2 and 3 SMA
- JEWELFISH – an open-label exploratory trial in people aged 12–60 with Type 2 or 3 SMA who have been previously treated with SMN-targeting therapy as part of a clinical study
A new trial, RAINBOWFISH in pre-symptomatic SMA, will be initiated by early 2019.
FIREFISH is an open-label, two-part pivotal clinical trial in infants with Type 1 SMA. Part 1 was a dose escalation study in 21 infants. The primary objective of Part 1 was to assess the safety profile of risdiplam in infants and determine the dose for Part 2. Part 2 is a pivotal, single-arm study of risdiplam in approximately 40 infants with Type 1 SMA for 24 months, followed by an open-label extension. The primary objective of Part 2 is to assess efficacy as measured by the proportion of infants sitting without support after 12 months of treatment, as assessed in the Gross Motor Scale of the Bayley Scales of Infant and Toddler Development – Third Edition (BSID-III) (defined as sitting without support for 5 seconds).
SUNFISH is a two-part double-blind, placebo-controlled pivotal clinical trial in children and young adults (two to 25 years old) with Type 2 and 3 SMA. Part 1 determined the dose for the confirmatory Part 2, and enrollment in Part 2 completed in September 2018.
About Genentech in neuroscience
Neuroscience is a major focus of research and development at Genentech and Roche. The company’s goal is to develop treatment options based on the biology of the nervous system to help improve the lives of people with chronic and potentially devastating diseases. Genentech and Roche have more than a dozen investigational medicines in clinical development for diseases that include multiple sclerosis, Alzheimer’s disease, spinal muscular atrophy, Parkinson’s disease, Huntington’s disease and autism spectrum disorder.
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.
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