CLINICAL PHARMACOLOGY
Mechanism Of Action
Sofosbuvir is a direct-acting antiviral agent against the
hepatitis C virus [see Microbiology].
Pharmacodynamics
Cardiac Electrophysiology
The effect of sofosbuvir 400 and 1200 mg (three times the
recommended dosage) on QTc interval was evaluated in a randomized, single-dose,
placebo-and active-controlled (moxifloxacin 400 mg) four period crossover
thorough QT trial in 59 healthy subjects. At a dosage three times the maximum
recommended dosage, SOVALDI does not prolong QTc to any clinically relevant
extent.
Pharmacokinetics
Absorption
The pharmacokinetic properties of sofosbuvir and the
predominant circulating metabolite GS-331007 have been evaluated in healthy
adult subjects and in subjects with chronic hepatitis C. Following oral
administration of SOVALDI, sofosbuvir was absorbed with a peak plasma
concentration observed at ~0.5â⬓2 hour post-dose, regardless of dose level. Peak
plasma concentration of GS-331007 was observed between 2 to 4 hours post-dose.
Based on population pharmacokinetic analysis in subjects with genotype 1 to 6
HCV infection who were coadministered ribavirin (with or without pegylated
interferon), geometric mean steady state AUC0-24 was 969 ngââ¬Â¢hr/mL for
sofosbuvir (N=838), and 6790 ngââ¬Â¢hr/mL for GS-331007 (N=1695). Relative to
healthy subjects administered sofosbuvir alone (N=272), the sofosbuvir AUC0-24 was
60% higher; and GS-331007 AUC0-24 was 39% lower, respectively, in HCV-infected
subjects. Sofosbuvir and GS-331007 AUCs are near dose proportional over the
dose range of 200 mg to 1200 mg.
Effect Of Food
Relative to fasting conditions, the administration of a
single dose of SOVALDI with a standardized high fat meal did not substantially
affect the sofosbuvir Cmax or AUC0-inf. The exposure of GS-331007 was not
altered in the presence of a high-fat meal. Therefore, SOVALDI can be
administered without regard to food.
Distribution
Sofosbuvir is approximately 61â⬓65% bound to human plasma
proteins and the binding is independent of drug concentration over the range of
1 microgram/mL to 20 microgram/mL. Protein binding of GS-331007 was minimal in
human plasma. After a single 400 mg dose of [14C]-sofosbuvir in
healthy subjects, the blood to plasma ratio of 14C-radioactivity was
approximately 0.7.
Metabolism
Sofosbuvir is extensively metabolized in the liver to
form the pharmacologically active nucleoside analog triphosphate GS-461203. The
metabolic activation pathway involves sequential hydrolysis of the carboxyl
ester moiety catalyzed by human cathepsin A (CatA) or carboxylesterase 1 (CES1)
and phosphoramidate cleavage by histidine triad nucleotide-binding protein 1
(HINT1) followed by phosphorylation by the pyrimidine nucleotide biosynthesis
pathway. Dephosphorylation results in the formation of nucleoside metabolite
GS-331007 that cannot be efficiently rephosphorylated and lacks anti-HCV
activity in vitro.
After a single 400 mg oral dose of [14C]-sofosbuvir,
sofosbuvir and GS-331007 accounted for approximately 4% and greater than 90% of
drug related material (sum of molecular weight-adjusted AUC of sofosbuvir and
its metabolites) systemic exposure, respectively.
Elimination
Following a single 400 mg oral dose of [14C]-sofosbuvir,
mean total recovery of the dose was greater than 92%, consisting of
approximately 80%, 14%, and 2.5% recovered in urine, feces, and expired air,
respectively. The majority of the sofosbuvir dose recovered in urine was
GS-331007 (78%) while 3.5% was recovered as sofosbuvir. These data indicate
that renal clearance is the major elimination pathway for GS-331007. The median
terminal half-lives of sofosbuvir and GS-331007 were 0.4 and 27 hours,
respectively.
Specific Populations
Race
Population pharmacokinetics analysis in HCV-infected
subjects indicated that race had no clinically relevant effect on the exposure
of sofosbuvir and GS-331007.
Gender
No clinically relevant pharmacokinetic differences have
been observed between men and women for sofosbuvir and GS-331007.
Pediatric Patients
The pharmacokinetics of sofosbuvir and GS-331007 were
determined in HCV genotype 2 or 3 infected pediatric subjects 3 years of age
and older receiving a daily dose of SOVALDI as described in Table 8. Exposures
in pediatric subjects were similar to those observed in adults.
Table 8 : Pharmacokinetic Properties of SOVALDI in
HCV-infected Pediatric Subjects 3 Years of Age and Oldera
Weight Group |
Dose |
PK Parameter |
Geometric Mean (%CV) |
Sofosbuvir |
GS-331007 |
≥35 kgb |
400 mg |
AUCtau (ng•hr/mL) |
1060 (50.6) |
7570 (32.8) |
Cmax (ng/mL) |
472 (53.0) |
572 (40.7) |
17 to <35 kgc |
200 mg |
AUCtau (ng•hr/mL) |
891 (36.1) |
10400 (31.6) |
Cmax (ng/mL) |
438 (26.4) |
866 (27.1) |
<17 kgd |
150 mg |
AUCtau (ng•hr/mL) |
851 (41.7) |
9060 (37.6) |
Cmax (ng/mL) |
418 (26.8) |
767 (28.3) |
aPopulation PK derived parameters
bSofosbuvir N=28; GS-331007 N=50
cSofosbuvir N=29; GS-331007 N=30
dSofosbuvir N=7; GS-331007 N=7 |
The pharmacokinetics of sofosbuvir and GS-331007 have not
been established in pediatric subjects less than 3 years of age [see Use In Specific
Populations and Clinical Studies].
Geriatric Patients
Population pharmacokinetic analysis in HCV-infected
subjects showed that within the age range (19 to 75 years) analyzed, age did
not have a clinically relevant effect on the exposure to sofosbuvir and
GS-331007 [see Use In Specific Populations].
Patients With Renal Impairment
The pharmacokinetics of sofosbuvir were studied in HCV
negative subjects with mild (eGFR between 50 to less than 80 mL/min/1.73m²),
moderate (eGFR between 30 to less than 50 mL/min/1.73m²), severe renal
impairment (eGFR less than 30 mL/min/1.73m²) and subjects with end stage renal
disease (ESRD) requiring hemodialysis following a single 400 mg dose of
sofosbuvir. Relative to subjects with normal renal function (eGFR greater than
80 mL/min/1.73m²), the sofosbuvir AUC0-inf was 61%, 107% and 171% higher in
mild, moderate and severe renal impairment, while the GS-331007 AUC0-inf was
55%, 88% and 451% higher, respectively. In subjects with ESRD, relative to
subjects with normal renal function, sofosbuvir and GS-331007 AUC0inf was 28%
and 1280% higher when sofosbuvir was dosed 1 hour before hemodialysis compared
with 60% and 2070% higher when sofosbuvir was dosed 1 hour after hemodialysis,
respectively. A 4 hour hemodialysis session removed approximately 18% of
administered dose. No dosage adjustment is required for patients with mild or
moderate renal impairment. The safety and efficacy of SOVALDI have not been
established in patients with severe renal impairment or ESRD. No dosage
recommendation can be given for patients with severe renal impairment or ESRD [see
DOSAGE AND ADMINISTRATION and Use In Specific Populations].
Patients With Hepatic Impairment
The pharmacokinetics of sofosbuvir were studied following
7-day dosing of 400 mg sofosbuvir in HCV-infected subjects with moderate and
severe hepatic impairment (Child-Pugh Class B and C). Relative to subjects with
normal hepatic function, the sofosbuvir AUC0-24 were 126% and 143% higher in
moderate and severe hepatic impairment, while the GS-331007 AUC0-24 were 18%
and 9% higher, respectively. Population pharmacokinetics analysis in
HCV-infected subjects indicated that cirrhosis had no clinically relevant
effect on the exposure of sofosbuvir and GS-331007. No dosage adjustment of
SOVALDI is recommended for patients with mild, moderate or severe hepatic
impairment [see Use In Specific Populations].
Assessment Of Drug Interactions
Sofosbuvir is a substrate of drug transporter P-gp and
breast cancer resistance protein (BCRP) while GS-331007 is not. Drugs that are
P-gp inducers in the intestine (e.g., rifampin or St. Johnâ⬙s wort) may decrease
sofosbuvir plasma concentration, leading to reduced therapeutic effect of
SOVALDI, and thus concomitant use with SOVALDI is not recommended [see WARNINGS
AND PRECAUTIONS and DRUG INTERACTIONS].
Coadministration of SOVALDI with drugs that inhibit P-gp
and/or BCRP may increase sofosbuvir plasma concentration without increasing
GS-331007 plasma concentration; accordingly, SOVALDI may be coadministered with
P-gp and/or BCRP inhibitors. Sofosbuvir and GS-331007 are not inhibitors of
P-gp and BCRP and thus are not expected to increase exposures of drugs that are
substrates of these transporters.
The intracellular metabolic activation pathway of
sofosbuvir is mediated by generally low affinity and high capacity hydrolase
and nucleotide phosphorylation pathways that are unlikely to be affected by
concomitant drugs.
The effects of coadministered drugs on the exposure of
sofosbuvir and GS-331007 are shown in Table 9. The effects of sofosbuvir on the
exposure of coadministered drugs are shown in Table 10 [see DRUG
INTERACTIONS].
Table 9 : Drug Interactions: Changes in
Pharmacokinetic Parameters for Sofosbuvir and the Predominant Circulating
Metabolite GS-331007 in the Presence of the Coadministered Druga
Coadministered Drug |
Dose of Coadministered Drug (mg) |
Sofosbuvir Dose (mg) |
N |
Mean Ratio (90% CI) of Sofosbuvir and GS-331007 PK With/Without Coadministered Drug No Effect=1.00 |
|
Cmax |
AUC |
Cmin |
Cyclosporine |
600 single dose |
400 single dose |
19 |
sofosbuvir |
2.54 (1.87, 3.45) |
4.53 (3.26, 6.30) |
NA |
GS-331007 |
0.60 (0.53, 0.69) |
1.04 (0.90, 1.20) |
NA |
Darunavir (boosted with ritonavir) |
800/100 once daily |
400 single dose |
18 |
sofosbuvir |
1.45 (1.10, 1.92) |
1.34 (1.12, 1.59) |
NA |
GS-331007 |
0.97 (0.90, 1.05) |
1.24 (1.18, 1.30) |
NA |
Efavirenzc |
600 once daily |
400 single dose |
16 |
sofosbuvir |
0.81 (0.60, 1.10) |
0.94 (0.76, 1.16) |
NA |
Emtricitabinec |
200 once daily |
Tenofovir disoproxil fumaratec |
300 once daily |
GS-331007 |
0.77 (0.70, 0.84) |
0.84 (0.76, 0.92) |
NA |
Methadone |
30 to 130 once daily |
400 once daily |
14 |
sofosbuvir |
0.95b (0.68, 1.33) |
1.30b (1.00, 1.69) |
NA |
GS-331007 |
0.73b (0.65, 0.83) |
1.04b (0.89, 1.22) |
NA |
Rilpivirine |
25 once daily |
400 single dose |
17 |
sofosbuvir |
1.21 (0.90, 1.62) |
1.09 (0.94, 1.27) |
NA |
GS-331007 |
1.06 (0.99, 1.14) |
1.01 (0.97, 1.04) |
NA |
Tacrolimus |
5 single dose |
400 single dose |
16 |
sofosbuvir |
0.97 (0.65, 1.43) |
1.13 (0.81, 1.57) |
NA |
GS-331007 |
0.97 (0.83, 1.14) |
1.00
(0.87, 1.13) |
NA |
NA = not available/not applicable
aAll interaction studies conducted in healthy volunteers
bComparison based on historic control
cAdministered as efavirenz/emtricitabine/tenofovir disoproxil
fumarate fixed dose tablet |
No effect on the pharmacokinetic parameters of sofosbuvir
and GS-331007 was observed with raltegravir.
Table 10 : Drug Interactions: Changes in
Pharmacokinetic Parameters for Coadministered Drug in the Presence of
Sofosbuvira
Coadministered Drug |
Dose of Coadministered Drug (mg) |
Sofosbuvir Dose (mg) |
N |
Mean Ratio (90% CI) of Coadministered Drug PK With/Without Sofosbuvir No Effect=1.00 |
Cmax |
AUC |
Cmin |
Norelgestromin |
norgestimate 0.18/0.215/0.25/ ethinyl estradiol 0.025 once daily |
400 once daily |
15 |
1.07 (0.94, 1.22) |
1.06 (0.92, 1.21) |
1.07 (0.89, 1.28) |
Norgestrel |
1.18 (0.99, 1.41) |
1.19 (0.98, 1.45) |
1.23 (1.00, 1.51) |
Ethinyl estradiol |
1.15 (0.97, 1.36) |
1.09 (0.94, 1.26) |
0.99 (0.80, 1.23) |
Raltegravir |
400 twice daily |
400 single dose |
19 |
0.57 (0.44, 0.75) |
0.73 (0.59, 0.91) |
0.95 (0.81, 1.12) |
Tacrolimus |
5 single dose |
400 single dose |
16 |
0.73 (0.59, 0.90) |
1.09 (0.84, 1.40) |
NA |
Tenofovir disoproxil fumarateb |
300 once daily |
400 single dose |
16 |
1.25 (1.08, 1.45) |
0.98 (0.91, 1.05) |
0.99 (0.91, 1.07) |
NA = not available/not applicable
aAll interaction studies conducted in healthy volunteers
bAdministered as efavirenz/emtricitabine/tenofovir disoproxil
fumarate fixed dose tablet |
No effect on the pharmacokinetic parameters of the
following coadministered drugs was observed with sofosbuvir: cyclosporine,
darunavir/ritonavir, efavirenz, emtricitabine, methadone, or rilpivirine.
Microbiology
Mechanism Of Action
Sofosbuvir is an inhibitor of the HCV NS5B RNA-dependent
RNA polymerase, which is essential for viral replication. Sofosbuvir is a
nucleotide prodrug that undergoes intracellular metabolism to form the
pharmacologically active uridine analog triphosphate (GS-461203), which can be
incorporated into HCV RNA by the NS5B polymerase and acts as a chain
terminator. In a biochemical assay, GS-461203 inhibited the polymerase activity
of the recombinant NS5B from HCV genotype 1b, 2a, 3a and 4a with IC50 values
ranging from 0.7 to 2.6 micromolar. GS-461203 is neither an inhibitor of human
DNA and RNA polymerases nor an inhibitor of mitochondrial RNA polymerase.
Antiviral Activity
In HCV replicon assays, the EC50 values of sofosbuvir
against full-length replicons from genotype 1a, 1b, 2a, 3a and 4a, and chimeric
1b replicons encoding NS5B from genotype 2b, 5a or 6a ranged from 0.014 to 0.11
micromolar. The median EC50 value of sofosbuvir against chimeric replicons
encoding NS5B sequences from clinical isolates was 0.062 micromolar for
genotype 1a (range 0.029â⬓0.128 micromolar; N=67), 0.102 micromolar for genotype
1b (range 0.045â⬓0.170 micromolar; N=29), 0.029 micromolar for genotype 2 (range
0.014â⬓0.081 micromolar; N=15) and 0.081 micromolar for genotype 3a (range
0.024â⬓0.181 micromolar; N=106). In infectious virus assays, the EC50 values of
sofosbuvir against genotype 1a and 2a were 0.03 and 0.02 micromolar,
respectively. The presence of 40% human serum had no effect on the anti-HCV
activity of sofosbuvir. Evaluation of sofosbuvir in combination with interferon
alpha or ribavirin showed no antagonistic effect in reducing HCV RNA levels in
replicon cells.
Resistance
In Cell Culture
HCV replicons with reduced susceptibility to sofosbuvir
have been selected in cell culture for multiple genotypes including 1b, 2a, 2b,
3a, 4a, 5a and 6a. Reduced susceptibility to sofosbuvir was associated with the
primary NS5B substitution S282T in all replicon genotypes examined. An M289L
substitution developed along with the S282T substitution in genotype 2a, 5 and
6 replicons. Site-directed mutagenesis of the S282T substitution in replicons
of 8 genotypes conferred 2-to 18-fold reduced susceptibility to sofosbuvir and
reduced the replication viral capacity by 89% to 99% compared to the
corresponding wild-type. In biochemical assays, recombinant NS5B polymerase
from genotypes 1b, 2a, 3a and 4a expressing the S282T substitution showed
reduced susceptibility to GS-461203 compared to respective wild-types.
In Clinical Trials
In a pooled analysis of 982 subjects who received SOVALDI
in Phase 3 trials, 224 subjects had post-baseline NS5B genotypic data from next
generation nucleotide sequencing (assay cutoff of 1%).
Treatment-emergent substitutions L159F (n=6) and V321A
(n=5) were detected in post-baseline samples from GT3a-infected subjects across
the Phase 3 trials. No detectable shift in the phenotypic susceptibility to
sofosbuvir of subject isolates with L159F or V321A substitutions was seen. The
sofosbuvir-associated resistance substitution S282T was not detected at
baseline or in the failure isolates from Phase 3 trials. However, an S282T
substitution was detected in one genotype 2b subject who relapsed at Week 4
post-treatment after 12 weeks of sofosbuvir monotherapy in the Phase 2 trial
P79770523 [ELECTRON]. The isolate from this subject displayed a mean 13.5-fold
reduced susceptibility to sofosbuvir. For this subject, the S282T substitution
was no longer detectable at Week 12 post-treatment by next generation
sequencing with an assay cutoff of 1%.
In the trial done in subjects with hepatocellular
carcinoma awaiting liver transplantation where subjects received up to 48 weeks
of sofosbuvir and ribavirin, the L159F substitution emerged in multiple
subjects with GT1a or GT2b HCV who experienced virologic failure (breakthrough
and relapse). Furthermore, the presence of substitutions L159F and/or C316N at
baseline was associated with sofosbuvir breakthrough and relapse
post-transplant in multiple subjects infected with GT1b HCV. In addition, S282R
and L320F substitutions were detected on-treatment by next generation
sequencing in a subject infected with GT1a HCV with a partial treatment
response.
The clinical significance of these substitutions is not
known.
Cross Resistance
HCV replicons expressing the sofosbuvir-associated
resistance substitution S282T were susceptible to NS5A inhibitors and
ribavirin. HCV replicons expressing the ribavirinassociated substitutions T390I
and F415Y were susceptible to sofosbuvir. Sofosbuvir was active against HCV
replicons with NS3/4A protease inhibitor, NS5B non-nucleoside inhibitor and
NS5A inhibitor resistant variants.
Clinical Studies
Description Of Clinical Trials
The safety and efficacy of SOVALDI was evaluated in five
Phase 3 trials in a total of 1724 HCV mono-infected subjects with genotypes 1
to 6 chronic hepatitis C virus, one Phase 3 trial in 223 HCV/HIV-1 coinfected
subjects with genotype 1, 2 or 3 HCV, and one trial in 106 pediatric subjects 3
years of age and older with genotype 2 or 3 HCV, as summarized in Table 11 [see
Clinical Studies].
Table 11 : Trials Conducted with SOVALDI with
Peginterferon Alfa and/or Ribavirin in Subjects with Chronic HCV Genotype 1, 2,
3, or 4 Infection
Trial |
Population |
Study Arms (Number of Subjects Treated) |
NEUTRINO a (NCT01641640) |
Treatment naive (TN) (GT1, 4, 5 or 6) |
SOVALDI + Peg-IFN alfa + RBV 12 weeks (327) |
FISSION a (NCT01497366) |
TN (GT2 or 3) |
SOVALDI + RBV 12 Weeks (256) Peg-IFN alfa + RBV 24 weeks (243) |
POSITRON b (NCT01542788) |
Interferon intolerant, ineligible or unwilling subjects (GT2 or 3) |
SOVALDI + RBV 12 Weeks (207) Placebo 12 weeks (71) |
FUSION b (NCT01604850) |
Previous interferon relapsers or nonresponders (GT2 or 3) |
SOVALDI + RBV 12 Weeks (103) SOVALDI + RBV 16 Weeks (98) |
VALENCEb (NCT01682720) |
TN or previous interferon relapsers or nonresponders (GT2 or 3) |
SOVALDI + RBV 12 Weeks for GT2 (73) SOVALDI + RBV 12 Weeks for GT3 (11) SOVALDI + RBV 24 Weeks for GT3 (250) Placebo for 12 weeks (85) |
PHOTON-1 a (NCT01667731) |
- HCV/HIV-1 coinfected TN (GT1)
- HCV/HIV-1 coinfected TN or previous interferon relapsers or nonresponders (GT2 or 3)
|
SOVALDI + RBV 24 Weeks for GT1 (114) SOVALDI + RBV 12 Weeks for GT2 or 3 TN (68) SOVALDI + RBV 24 Weeks for GT2 or 3 previous interferon relapsers or nonresponders (41) |
1112 (NCT02175758)a |
GT2 or GT3 pediatric subjects 3 years of age and older |
SOVALDI + RBV 12 Weeks for GT2 (31) SOVALDI + RBV 24 Weeks for GT3 (75) |
aOpen label.
bDouble-blind, placebo-controlled. |
Subjects in the adult trials did not have cirrhosis or
had compensated cirrhosis. SOVALDI was administered at a dose of 400 mg once
daily. The ribavirin (RBV) dosage for adult subjects was weight-based at
1000-1200 mg daily administered in two divided doses when used in combination
with SOVALDI, and the peginterferon alfa 2a dosage, where applicable, was 180
micrograms per week. Treatment duration was fixed in each trial and was not
guided by subjectsâ⬙ HCV RNA levels (no response guided algorithm). Plasma HCV
RNA values were measured during the clinical trials using the COBAS TaqMan HCV
test (version 2.0), for use with the High Pure System. The assay had a lower limit
of quantification (LLOQ) of 25 IU per mL. Sustained virologic response (SVR12)
was the primary endpoint which was defined as HCV RNA less than LLOQ at 12
weeks after the end of treatment.
Clinical Trials In Subjects With Genotype 1 Or 4 HCV
Treatment-Naive Adults - NEUTRINO (Study 110)
NEUTRINO was an open-label, single-arm trial that
evaluated 12 weeks of treatment with SOVALDI in combination with peginterferon
alfa 2a and ribavirin in treatment-naive subjects with genotype 1, 4, 5 or 6
HCV infection compared to pre-specified historical control.
Treated subjects (N=327) had a median age of 54 years
(range: 19 to 70); 64% of the subjects were male; 79% were White, 17% were
Black; 14% were Hispanic or Latino; mean body mass index was 29 kg/m² (range:
18 to 56 kg/m²); 78% had baseline HCV RNA greater than 6 log10 IU per mL; 17%
had cirrhosis; 89% had HCV genotype 1; 9% had HCV genotype 4 and 2% had HCV
genotype 5 or 6. Table 12 presents the SVR12 for the treatment group of SOVALDI
+ peginterferon alfa + ribavirin in subjects with genotype 1 or 4 HCV.
Available data on subjects with genotype 5 or 6 HCV treated with SOVALDI +
peginterferon alfa + ribavirin for 12 weeks were insufficient for dosing
recommendations; therefore these results are not presented in Table 12 [see Use
In Specific Populations].
Table 12 : Study NEUTRINO: SVR12 for Treatment-Naive
Subjects with Genotype 1 or 4 HCV
|
SOVALDI + Peg-IFN alfa + RBV 12 weeks
N=320 |
Overall SVR |
90% (289/320) |
Genotype 1a |
90% (262/292) |
Genotype 1a |
92% (206/225) |
Genotype 1b |
83% (55/66) |
Genotype 4 |
96% (27/28) |
Outcome for subjects without SVR |
On-treatment virologic failure |
0/320 |
Relapseb |
9% (28/319) |
Otherc |
1% (3/320) |
aOne subject had genotype 1a/1b mixed
infection.
bThe denominator for relapse is the number of subjects with HCV RNA
<LLOQ at their last on-treatment assessment.
cOther includes subjects who did not achieve SVR and did not meet
virologic failure criteria (e.g., lost to follow-up). |
SVR12 for selected subgroups are presented in Table 13.
Table 13 : SVR12 Rates for Selected Subgroups in
NEUTRINO in Subjects with Genotype 1 or 4 HCV
|
SOVALDI + Peg-IFN alfa + RBV 12 weeks |
Cirrhosis |
No |
93% (247/267) |
Yes |
79% (42/53) |
Race |
Black |
87% (47/54) |
Non-black |
91% (242/266) |
Multiple Baseline Factors |
Genotype 1, Metavir F3/F4 fibrosis, IL28B non-C/C, HCV RNA >800,000 lU/mL |
71% (37/52) |
SVR12 rates were 99% (89/90) in subjects with genotype 1
or 4 HCV and baseline IL28B C/C allele and 87% (200/230) in subjects with
genotype 1 or 4 HCV and baseline IL28B non-C/C alleles.
It is estimated that the SVR12 in patients who previously
failed pegylated interferon and ribavirin therapy will approximate the observed
SVR12 in NEUTRINO subjects with multiple baseline factors traditionally
associated with a lower response to interferon-based treatment (Table 13).
The SVR12 rate in the NEUTRINO trial in genotype 1
subjects with IL28B non-C/C alleles, HCV RNA greater than 800,000 IU/mL and
Metavir F3/F4 fibrosis was 71% (37/52).
Clinical Trials In Subjects With Genotype 2 Or 3 HCV
Treatment-Naive Adults - FISSION (Study 1231)
FISSION was a randomized, open-label, active-controlled
trial that evaluated 12 weeks of treatment with SOVALDI and ribavirin compared
to 24 weeks of treatment with peginterferon alfa 2a and ribavirin in
treatment-naive subjects with genotype 2 and 3 HCV. The ribavirin dosage used
in the SOVALDI + ribavirin and peginterferon alfa 2a + ribavirin arms were
weight-based 1000-1200 mg per day and 800 mg per day regardless of weight,
respectively. Subjects were randomized in a 1:1 ratio and stratified by
cirrhosis (presence vs. absence), HCV genotype (2 vs. 3) and baseline HCV RNA
level (less than 6 log10 IU/mL vs. at least 6 log10 IU/mL). Subjects with
genotype 2 or 3 HCV were enrolled in an approximately 1:3 ratio.
Treated subjects (N=499) had a median age of 50 years
(range: 19 to 77); 66% of the subjects were male; 87% were White, 3% were
Black; 14% were Hispanic or Latino; mean body mass index was 28 kg/m² (range:
17 to 52 kg/m²); 57% had baseline HCV RNA levels greater than 6 log10 IU per
mL; 20% had cirrhosis; 72% had HCV genotype 3.
Table 14 presents the SVR12 for the treatment groups of
SOVALDI + ribavirin and peginterferon alfa + ribavirin in subjects with
genotype 2 HCV. SVR12 for genotype 3 subjects treated with SOVALDI + ribavirin
for 12 weeks was suboptimal; therefore these results are not presented in Table
14.
Table 14 : Study FISSION: SVR12 in Treatment-Naive
Subjects with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=73a |
Peg-IFN alfa + RBV 24 weeks
N=67a |
SVR12 |
95% (69/73) |
78% (52/67) |
Outcome for subjects without SVR12 |
On-treatment virologic failure |
0/73 |
4% (3/67) |
Relapseb |
5% (4/73) |
15% (9/62) |
Otherc |
0/73 |
4% (3/67) |
aIncluding three subjects with recombinant
genotype 2/1 HCV infection.
bThe denominator for relapse is the number of subjects with HCV RNA
<LLOQ at their last on-treatment assessment.
cOther includes subjects who did not achieve SVR and did not meet
virologic failure criteria (e.g., lost to follow-up). |
SVR12 for genotype 2 HCV-infected subjects with cirrhosis
at baseline are presented in Table 15.
Table 15 : SVR12 Rates by Cirrhosis in Study FISSION
in Subjects with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=73 |
Peg-IFN alfa + RBV 24 weeks
N=67 |
Cirrhosis |
No |
97% (59/61) |
81% (44/54) |
Yes |
83% (10/12) |
62% (8/13) |
Interferon Intolerant, Ineligible Or Unwilling Adults
- POSITRON (Study 0107)
POSITRON was a randomized, double-blinded,
placebo-controlled trial that evaluated 12 weeks of treatment with SOVALDI and
ribavirin (N=207) compared to placebo (N=71) in subjects who are interferon
intolerant, ineligible or unwilling. Subjects were randomized in 3:1 ratio and
stratified by cirrhosis (presence vs. absence).
Treated subjects (N=278) had a median age of 54 years
(range: 21 to 75); 54% of the subjects were male; 91% were White, 5% were
Black; 11% were Hispanic or Latino; mean body mass index was 28 kg/m² (range:
18 to 53 kg/m²); 70% had baseline HCV RNA levels greater than 6 log10 IU per
mL; 16% had cirrhosis; 49% had HCV genotype 3. The proportions of subjects who
were interferon intolerant, ineligible, or unwilling were 9%, 44%, and 47%,
respectively. Most subjects had no prior HCV treatment ÃÂ (81%). Table 16
presents the SVR12 for the treatment groups of SOVALDI + ribavirin and placebo
in subjects with genotype 2 HCV. SVR12 for genotype 3 subjects treated with
SOVALDI + ribavirin for 12 weeks was suboptimal; therefore these results are
not presented in Table 16.
Table 16 : Study POSITRON: SVR12 in Interferon
Intolerant, Ineligible or Unwilling Subjects with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=109 |
Placebo 12 weeks
N= 34 |
SVR12 |
93% (101/109) |
0/34 |
Outcome for subjects without SVR12 |
On-treatment virologic failure |
0/109 |
97% (33/34) |
Relapsea |
5% (5/107) |
0/0 |
Otherb |
3% (3/109) |
3% (1/34) |
aThe denominator for relapse is the number of
subjects with HCV RNA <LLOQ at their last on-treatment assessment.
bOther includes subjects who did not achieve SVR and did not meet
virologic failure criteria (e.g., lost to follow-up). |
Table 17 presents the subgroup analysis for cirrhosis and
interferon classification in subjects with genotype 2 HCV.
Table 17 : SVR12 Rates for Selected Subgroups in
POSITRON in Subjects with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=109 |
Cirrhosis |
No |
92% (85/92) |
Yes |
94% (16/17) |
Interferon Classification |
Ineligible |
88% (36/41) |
Intolerant |
100% (9/9) |
Unwilling |
95% (56/59) |
Previously Treated Adults - FUSION (Study 0108)
FUSION was a randomized, double-blinded trial that
evaluated 12 or 16 weeks of treatment with SOVALDI and ribavirin in subjects
who did not achieve SVR with prior interferon-based treatment (relapsers and
nonresponders). Subjects were randomized in a 1:1 ratio and stratified by
cirrhosis (presence vs. absence) and HCV genotype (2 vs. 3).
Treated subjects (N=201) had a median age of 56 years
(range: 24 to 70); 70% of the subjects were male; 87% were White; 3% were
Black; 9% were Hispanic or Latino; mean body mass index was 29 kg/m² (range: 19
to 44 kg/m²); 73% had baseline HCV RNA levels greater than 6 log10 IU per mL;
34% had cirrhosis; 63% had HCV genotype 3; 75% were prior relapsers. Table 18
presents the SVR12 for the treatment groups of SOVALDI + ribavirin for 12 weeks
in subjects with genotype 2 HCV. Treatment of 16 weeks in subjects with
genotype 2 HCV was not shown to increase the SVR12 observed with 12 weeks of
treatment. SVR12 for genotype 3 subjects treated with SOVALDI + ribavirin for
12 or 16 weeks was suboptimal; therefore these results are not presented in
Table 18.
Table 18 : Study FUSION: SVR12 in Previous Interferon
Relapsers and Nonresponders with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=39a |
SVR12 |
82% (32/39) |
Outcome for subjects without SVR12 |
On-treatment virologic failure |
0/39 |
Relapseb |
18% (7/39) |
Otherc |
0/39 |
aIncluding three subjects with recombinant
genotype 2/1 HCV infection.
bThe denominator for relapse is the number of subjects with HCV RNA
<LLOQ at their last on-treatment assessment.
cOther includes subjects who did not achieve SVR and did not meet
virologic failure criteria (e.g., lost to follow-up). |
Table 19 presents the subgroup analysis for cirrhosis and
response to prior HCV treatment in subjects with genotype 2 HCV.
Table 19 : SVR12 Rates for Selected Subgroups in Study
FUSION in Subjects with Genotype 2 HCV
|
SOVALDI + RBV 12 weeks
N=39 |
Cirrhosis |
No |
90% (26/29) |
Yes |
60% (6/10) |
Response to prior HCV treatment |
Relapser/ breakthrough |
86% (25/29) |
Nonresponder |
70% (7/10) |
Treatment-Naive And Previously Treated Adults -
VALENCE (Study 0133)
The VALENCE trial evaluated SOVALDI in combination with
weight-based ribavirin for the treatment of genotype 2 or 3 HCV infection in
treatment-naive subjects or subjects who did not achieve SVR with prior
interferon-based treatment, including subjects with compensated cirrhosis. The
original trial design was a 4 to 1 randomization to SOVALDI + ribavirin for 12
weeks or placebo. Based on emerging data, this trial was unblinded and all
genotype 2 HCV-infected subjects continued the original planned treatment and
received SOVALDI + ribavirin for 12 weeks, and duration of treatment with
SOVALDI + ribavirin in genotype 3 HCV-infected subjects was extended to 24
weeks. Eleven genotype 3 subjects had already completed SOVALDI + ribavirin for
12 weeks at the time of the amendment.
Treated subjects (N=419) had a median age of 51 years
(range: 19 to 74); 60% of the subjects were male; mean body mass index was 26
kg/m² (range: 17 to 44 kg/m²); the mean baseline HCV RNA level was 6.4 log10 IU
per mL; 78% had HCV genotype 3; 58% of the subjects were treatment-experienced
and 65% of those subjects experienced relapse/breakthrough to prior HCV
treatment.
Table 20 presents the SVR12 for the treatment groups of
SOVALDI + ribavirin for 12 weeks and 24 weeks.
Table 20 : Study VALENCEa: SVR12 in
Subjects with Genotype 2 or 3 HCV Who were Treatment-Naive or Who Did
Not Achieve SVR12 with Prior Interferon-Based Treatment
|
Genotype 2 SOVALDI + RBV 12 weeks
N=73 |
Genotype 3 SOVALDI + RBV 24 weeks
N=250 |
Overall SVR |
93% (68/73) |
84% (210/250) |
Outcome for subjects without SVR |
On-treatment virologic failure |
0% (0/73) |
<1% (1/250) |
Relapseb |
7% (5/73) |
14% (34/249) |
Treatment-naive |
3% (1/32) |
5% (5/105) |
Treatment-experienced |
10% (4/41) |
20% (29/144) |
Otherc |
0% (0/73) |
2% (5/250) |
aPlacebo subjects (N=85) were not included as
none achieved SVR12.
bThe denominator for relapse is the number of subjects with HCV RNA
<LLOQ at their last on-treatment assessment.
cOther includes subjects who did not achieve SVR12 and did not meet
virologic failure criteria (e.g., lost to follow-up). |
Table 21 presents the subgroup analysis by genotype for
cirrhosis and prior HCV treatment experience.
Table 21 : SVR12 Rates for Selected Subgroups by
Genotype in Study VALENCE in Subjects with Genotype 2 or 3 HCV
|
Genotype 2 SOVALDI + RBV 12 weeks
N=73 |
Genotype 3 SOVALDI + RBV 24 weeks
N=250 |
Treatment-naive |
97% (31/32) |
93% (98/105) |
Non-cirrhotic |
97% (29/30) |
93% (86/92) |
Cirrhotic |
100% (2/2) |
92% (12/13) |
T reatment-experienced |
90% (37/41) |
77% (112/145) |
Non-cirrhotic |
91% (30/33) |
85% (85/100) |
Cirrhotic |
88% (7/8) |
60% (27/45) |
Clinical Trials In Adult Subjects Coinfected With HCV And
HIV-1 - Photon-1 (Study 0123)
SOVALDI was studied in an open-label clinical trial
(Study PHOTON-1) evaluating the safety and efficacy of 12 or 24 weeks of treatment
with SOVALDI and ribavirin in adult subjects with genotype 1, 2 or 3 chronic
hepatitis C coinfected with HIV-1. Genotype 2 and 3 subjects were either HCV
treatment-naive or experienced, whereas genotype 1 subjects were all
treatment-naive. Subjects received 400 mg SOVALDI and weight-based ribavirin
(1000 mg for subjects weighing less than 75 kg or 1200 mg for subjects weighing
at least 75 kg) daily for 12 or 24 weeks based on genotype and prior treatment
history. Subjects were either not on antiretroviral therapy with a CD4+ cell
count greater than 500 cells/mm³ or had virologically suppressed HIV-1 with a
CD4+ cell count greater than 200 cells/mm³ . Efficacy data 12 weeks post
treatment are available for 210 subjects (see Table 22).
Table 22 : Study PHOTON-1a: SVR12 in Treatment-Naive
or Treatment-Experienced Subjects with Genotype 1, 2, or 3 HCV
|
HCV genotype 1 |
HCV genotype 2 |
HCV genotype 3 |
SOVALDI + RBV 24 weeks TN
(N=114) |
SOVALDI + RBV 12 weeks TN
(N=26) |
SOVALDI + RBV 24 weeks TE
(N=13) |
Overall |
76% (87/114) |
88% (23/26) |
92% (12/13) |
Outcome for subjects without SVR12 |
On-treatment virologic failure |
1% (1/114) |
4% (1/26) |
0/13 |
Relapseb |
22% (25/113) |
0/25 |
8% (1/13) |
Otherc |
1% (1/114) |
8% (2/26) |
0/13 |
TN = Treatment-naive; TE = Treatment-experienced
aSubjects with genotype 2 HCV treated with SOVALDI + RBV for 24
weeks (N=15) and subjects with genotype 3 HCV treated with SOVALDI + RBV for 12
weeks (N=42) are not included in the table.
bThe denominator for relapse is the number of subjects with HCV RNA
<LLOQ at their last on-treatment assessment.
cOther includes subjects who did not achieve SVR12 and did not meet
virologic failure criteria (e.g., lost to follow-up). |
In subjects with HCV genotype 1 infection, the SVR12 rate
was 82% (74/90) in subjects with genotype 1a infection and 54% (13/24) in subjects
with genotype 1b infection, with relapse accounting for the majority of
treatment failures. SVR12 rates in subjects with HCV genotype 1 infection were
80% (24/30) in subjects with baseline IL28B C/C allele and 75% (62/83) in
subjects with baseline IL28B non-C/C alleles.
In the 223 HCV subjects with HIV-1 coinfection, the
percentage of CD4+ cells did not change during treatment. Median CD4+ cell
count decreases of 85 cells/mm³ and 84 cells/mm³ were observed at the end of
treatment with SOVALDI + ribavirin for 12 or 24 weeks, respectively. HIV-1
rebound during SOVALDI + ribavirin treatment occurred in 2 subjects (0.9%) on
antiretroviral therapy.
Clinical Trial In Pediatrics (Study 1112)
The efficacy of SOVALDI in HCV-infected pediatric
subjects 3 years of age and older was evaluated in 106 subjects with HCV
genotype 2 (N = 31) or genotype 3 (N = 75) in a Phase 2, open label clinical
trial. Subjects with HCV genotype 2 or 3 infection in the trial were treated
with SOVALDI and weight-based ribavirin for 12 or 24 weeks, respectively [see DOSAGE
AND ADMINISTRATION].
Subjects 12 Years to <18 Years of Age: SOVALDI was
evaluated in 52 subjects12 years to <18 years of age with HCV genotype 2 (N
= 13) or genotype 3 (N = 39) infection. The median age was 15 years (range: 12
to 17); 40% of the subjects were female; 90% were White, 4% were Black, and 2%
were Asian; 4% were Hispanic/Latino; mean body mass index was 22 kg/m² (range:
16 to 32 kg/m²);mean weight was 60 kg (range: 30 to 101 kg); 17% were treatment
experienced; 65% had baseline HCV RNA levels greater than or equal to 800,000
IU/mL; and no subjects had known cirrhosis. The majority of subjects (71%) had
been infected through vertical transmission.
The SVR12 rate was 100% [13/13] in genotype 2 subjects
and 97% [38/39] in genotype 3 subjects. No subject experienced on-treatment
virologic failure or relapse.
Subjects 6 Years To <12 Years Of Age
SOVALDI was evaluated in 41 subjects 6 years to <12
years of age with HCV genotype 2 (N = 13) or genotype 3 (N = 28) infection. The
median age was 9 years (range: 6 to 11); 73% of the subjects were female; 71%
were White and 20% were Asian; 15% were Hispanic/Latino; mean body mass index
was 19 kg/m² (range: 13 to 32 kg/m²); mean weight was 34
kg (range 15 to 80 kg); 98% were treatment naive; 46% had baseline HCV RNA
levels greater than or equal to 800,000 IU/mL; and no subjects had known
cirrhosis. The majority of subjects (98%) had been infected through vertical
transmission.
The SVR12 rate was 100% (13/13) in genotype 2 and 100%
(28/28) in genotype 3 subjects.). No subjects experienced on-treatment
virologic failure or relapse.
Subjects 3 Years To <6 Years Of Age
SOVALDI was evaluated in 13 subjects 3 years to <6
years of age with HCV genotype 2 (N = 5) or genotype 3 (N = 8) infection. The
median age was 4 years (range: 3 to 5); 77% of the subjects were female; 69%
were White, 8% were Black, and 8% were Asian; 8% were Hispanic/Latino; mean
body mass index was 15 kg/m² (range: 13 to 17 kg/m²); mean weight was 17 kg
(range 13 to 19 kg); 100% were treatment naive; 23% had baseline HCV RNA levels
greater than or equal to 800,000 IU/mL; and no subjects had known cirrhosis.
The majority of subjects (85%) had been infected through vertical transmission.
The SVR12 rate was 80% (4/5) in genotype 2 subjects and
100% (8/8) in genotype 3 subjects. No subjects experienced on-treatment
virologic failure or relapse. One subject prematurely discontinued study
treatment due to an adverse event.