PTC Therapeutics (NASDAQ:
PTCT) slips
6% premarket on light volume on the heels of
one-year data from Part 2 of a Phase 2/3 clinical trial,
SUNFISH, conducted by licensee Roche (
OTCQX:RHHBY) evaluating risdiplam in patients aged 2 – 25 with nonambulatory type 2 & 3 spinal muscular atrophy (SMA).
The data showed that treatment with risdimplam, an
oral mRNA splicing modifier, resulted in a statistically significant
improvement in motor function at month 12 from baseline as measured by a
scale called MFM-32 compared to placebo.
The company says no new safety signals were
observed but there was a range of adverse events that investors may be
reacting to: upper respiratory tract infection (31.7%), nasopharyngitis
(25.8%), pyrexia (20.8%), headache (20%), diarrhea (16.7%), vomiting
(14.2%) and cough (14.2%). The rates of lower respiratory tract
infections were similar between risdiplam (19%) and placebo (20%), the
rate of serious lower respiratory tract infections was higher in the
treatment group (10%) versus the control arm (2%), although deemed
unrelated to risdiplam.
By comparison, the most common adverse events in studies of Biogen’s (NASDAQ:
BIIB)
Spinraza were lower respiratory tract infection (43%), upper
respiratory tract infection (39%), constipation (30%), teething (14%)
and upper respiratory tract congestion (6%).
Roche’s U.S. marketing application is currently under FDA review with an action date of May 24 (Priority Review status).
https://seekingalpha.com/news/3539181-ptc-therapeutics-down-6-premarket-on-risdiplam-data
