either an inadequate response or intolerance to ursodeoxycholic
acid (UDCA) were randomized to daily seladelpar at 5 or 10 mg.
After 12 weeks, patients on 5 mg could escalate to 10 mg if their
alkaline phosphatase (ALP) treatment goal was not met (5/10 mg
group). The primary efficacy outcome was the ALP % change from
baseline. At 52 weeks, the mean decreases in ALP were
-47%
and
-46%
in the 5/10 and 10 mg groups, respectively. A key secondary outcome
was the composite response measured at week 52, where a responder
was defined as a patient with ALP <1.67 x ULN,
³
15% decrease in ALP, and total bilirubin
£
ULN. At 52 weeks, 59% and 71% of patients met the composite
endpoint in the 5/10 and 10 mg groups, respectively. The
anti-cholestatic effect of seladelpar was further substantiated
with normalization of ALP levels at 52 weeks in 24% and 29% of
patients in the 5/10 and 10 mg groups, respectively. Treatment with
seladelpar also demonstrated a robust anti-inflammatory activity
with median transaminase decreases of
-31%
and
-33%
in the 5/10 and 10 mg groups, respectively.
A
26-week
analysis from the study was also shared on the effect of seladelpar
on pruritus, or itching, which is a common clinical symptom of PBC
that adversely effects a patient’s quality of life. After 26 weeks,
the median changes in the pruritus visual analog scale (VAS) was
-50%
and
-55%
in the 5 /10 and 10 mg groups, respectively. These data suggest
that seladelpar is not associated with drug-induced pruritus and
support further evaluation of seladelpar’s potential benefit on
pruritus.
In February 2019, the FDA granted seladelpar Breakthrough Therapy
Designation for the treatment of early stage PBC, and in October
2016, seladelpar received EMA PRIority MEdicines (PRIME)
designation for the treatment of PBC. In November 2016, the FDA
granted orphan drug designation to seladelpar for the treatment of
PBC, and in September 2017, the EMA’s Committee for Orphan
Medicinal Products (COMP) granted orphan drug designation to
seladelpar for the treatment of PBC.
Nonalcoholic
Steatohepatitis (NASH)
In February 2019, we completed enrollment of a placebo-controlled
Phase 2b
study to evaluate seladelpar at three doses in biopsy-proven NASH.
The primary efficacy outcome was the change from baseline in liver
fat content at 12 weeks measured by magnetic resonance imaging
using the proton density fat fraction method
(MRI-PDFF).
The study also included pathology assessments of liver biopsy
samples at baseline and at 52 weeks to examine the potential of
seladelpar treatment to resolve NASH and/or decrease fibrosis. In
preclinical studies, seladelpar was found to reverse NASH
pathology, decrease fibrosis, inflammation, hepatic lipids and
reverse insulin resistance in the
mouse which is a diabetic obese model of NASH.
Primary Sclerosing
Cholangitis (PSC)
In June 2019, we initiated a Phase 2 randomized,
placebo-controlled, dose-ranging study of seladelpar in patients
with PSC to enroll approximately 100 patients at 60 sites
globally. Seladelpar at doses of 5, 10, and 25 mg once daily
was to be studied versus placebo in a 1:1:1:1 randomization. The
primary efficacy outcome was to be the relative change in alkaline
phosphatase (ALP) from baseline at 24 weeks.
Recent Developments
in the Seladelpar Program
In November 2019, the Phase 2b study of seladelpar in subjects with
NASH and the Phase 2 study of seladelpar in patients with PSC were
terminated due to histological findings identified by study
pathologists during the evaluation of planned liver biopsies in the
NASH study. In December 2019, the ongoing studies of seladelpar in
subjects with PBC were also terminated and all development programs
for seladelpar were placed on clinical hold. In May 2020, we
announced completion of an independent expert panel review into the
findings from our NASH Phase 2b study. The eight-person panel
included three hepatopathologists and five hepatologists with
expertise in drug-induced liver injury, NASH and PBC. The panel
unanimously concluded that the data, in aggregate, did not support
liver injury related to seladelpar. The panel also unanimously
supported lifting the clinical hold and
re-initiation
of clinical development. In June 2020, we discussed the data, the
panel’s conclusions, and other matters with the FDA and submitted a
complete response letter to answer outstanding FDA questions and
seek approval from the FDA to lift the clinical hold. In July 2020,
we received a response from the FDA lifting the clinical hold,
thereby permitting us to reinstate clinical development of
seladelpar.
In August 2020, we announced positive results from ENHANCE, a phase
3 study, which demonstrated seladelpar appeared to be safe,
well-tolerated, and efficacious in patients with PBC. ENHANCE was a
double-blind, placebo-controlled, global study that randomized 265
patients to placebo, 5 mg of seladelpar, or 10 mg of seladelpar
once daily. Although the study was terminated prior to the
completion of the
52-week
treatment period, the statistical analysis plan was amended while
the study remained blinded to adjust for evaluation of the primary
and two key secondary endpoints at week 12 rather than week 52.
Topline data for patients through 12 and to 26 weeks showed robust
anti-cholestatic, anti-inflammatory and anti-pruritic activity of
seladelpar. Specifically, 78.2% of patients on 10 mg of seladelpar
compared with 12.5% on placebo achieved the primary composite
outcome after 3 months (p<0.0001), and 27.3% of patients on 10
mg of seladelpar compared with 0% on placebo normalized ALP by 3
months (p<0.0001). In addition, the study revealed statistically
significant improvement in pruritus at 3 months (p<0.05) for
patients with
itch treated with seladelpar 10 mg versus placebo.