risdiplam- RG7916 is well tolerated at all dose levels with no drug-related safety findings –
SOUTH PLAINFIELD, N.J., June 16, 2018 /PRNewswire/ — PTC Therapeutics, Inc. (NASDAQ: PTCT) today announced the presentation of updated interim clinical data from Part 1 of the FIREFISH study investigating risdiplam (RG7916) in babies with Type 1 Spinal Muscular Atrophy (SMA), at the 22nd Annual SMA Researcher Meeting. The data presented by Dr. Baranello demonstrated that at Day 182, over 90% of the babies achieved a greater than 4-point increase in CHOP-INTEND score compared to baseline. The CHOP-INTEND data were further supported by video footage presented by Dr Baranello demonstrating antigravity movements, the ability to control their head, roll, or sit in babies participating in FIREFISH. Part 2 of the pivotal FIREFISH study is ongoing. The SMA program is a collaboration between PTC, Roche, and the SMA Foundation.
”We are delighted that up to 6.5-fold increase of protein production has translated into clinical impact for these babies in the FIREFISH study,” said Stuart W. Peltz, Ph.D. Chief Executive Officer of PTC Therapeutics. ”The survival data and CHOP-INTEND scores are very promising, since babies with Type 1 SMA typically do not experience functional motor milestone improvement based on natural history. We look forward to sharing updates for the programs as the data further develop at upcoming medical meetings.”
The Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) is a test designed to measure motor milestone development of patients with SMA Type 1. In the FIREFISH study the median increases in CHOP-INTEND scores were 5.5 points (n=20) at Day 56, 12.5 points (n=16) at Day 119, and 14 points (n=11) at Day 182 of treatment. The proportion of patients achieving greater than a four-point increase from baseline in CHOP-INTEND scores was 75% at Day 56 (n=20), 94% at Day 119 (n=16), and 91% (n=11) at Day 182. In addition, risdiplam has been well tolerated at all dose levels and to date there have been no drug-related safety findings leading to withdrawal. Also, no babies have required a tracheostomy or permanent ventilation since study initiation and no baby has lost the ability to swallow. Median age of patients at first dose in the FIREFISH trial is 6.7 months; oldest patient in the trial is currently 23.8 months old.
”I am impressed by the clinical data and the changes reported by the patients’ families,” stated Dr. Giovanni Baranello, Fondazione Istituto Neurologico Carlo Besta in Milan, Italy. ”Data on motor function seem more encouraging when we consider that we are seeing motor function improvements and milestones achievement at this early stage of the study, which was essentially a dose-finding study and most of the infants included have received their first dose after the age of 5 months. It is exciting to see evidence of clinical benefit from a systemic oral treatment for SMA.”
Risdiplam is an investigational splicing modifier targeting the survival motor neuron 2 (SMN2) RNA, restoring a functional transcript. Risdiplam is taken orally, crosses the blood brain barrier, and shows systemic distribution to the organs that are affected by low levels of SMN protein.
Other presentations included an analysis of data from Part 1 of the SUNFISH study which demonstrated that risdiplam administration resulted in a dose-dependent increase in SMN protein levels up to 3.5-fold; pharmacodynamic data from the JEWELFISH trial; and preclinical data demonstrating SMN protein production and distribution, as well as the development of the SMA Independence Scale (SMAIS).
SUNFISH: A double‐blind, two‐part, placebo‐controlled trial. Part 1 enrolled patients with Type 2 or 3 SMA to evaluate safety, tolerability, and PK/PD of several risdiplam dose levels. The pivotal SUNFISH Part 2, in non‐ambulant patients with Type 2 or 3 SMA, is evaluating safety and efficacy of the risdiplam dose level selected from Part 1 for 24 months, followed by an open label extension. This study is recruiting globally.
JEWELFISH: An ongoing, exploratory, open-label study to establish the safety and tolerability of risdiplam in people who have previously participated in a study with another therapy targeting SMN2 splicing.