CLINICAL PHARMACOLOGY
Mechanism Of Action
Netupitant is a selective antagonist of human substance
P/neurokinin 1 (NK-1) receptors.
Palonosetron is a 5-HT3 receptor antagonist with a strong
binding affinity for this receptor and little or no affinity for other
receptors. Cancer chemotherapy may be associated with a high incidence of
nausea and vomiting, particularly when certain agents, such as cisplatin, are
used. 5HT3 receptors are located on the nerve terminals of the vagus in the
periphery and centrally in the chemoreceptor trigger zone of the area postrema.
Chemotherapeutic agents produce nausea and vomiting by stimulating the release
of serotonin from the enterochromaffin cells of the small intestine. Serotonin
then activates 5-HT3 receptors located on vagal afferents to initiate the
vomiting reflex. The development of acute emesis is known to depend on
serotonin and its 5-HT3 receptors have been demonstrated to selectively
stimulate the emetic response.
Delayed emesis has been largely associated with the
activation of tachykinin family neurokinin 1 (NK-1) receptors (broadly
distributed in the central and peripheral nervous systems) by substance P. As
shown in in vitro and in vivo studies, netupitant inhibits substance P mediated
responses.
Pharmacodynamics
NK-1 Receptor Occupancy
The receptor occupancy of netupitant was measured in a
human Positron Emission Tomography (PET) study. Netupitant was shown to cross
the blood brain barrier with a NK-1 receptor occupancy of 92.5%, 86.5%, 85.0%,
78.0%, and 76.0% in striatum at 6, 24, 48, 72, and 96 hours, respectively,
after oral administration of 300 mg netupitant.
Cardiac Electrophysiology
An AKYNZEO oral dose of 600 mg netupitant (2 times the
recommended dose) and 1.5 mg palonosetron (3 times the recommended dose) did
not prolong the QT interval to any clinically relevant extent.
The recommended dose of AKYNZEO for injection (235 mg
fosnetupitant and 0.25 mg palonosetron) did not prolong the QT interval to any
clinically relevant extent.
Pharmacokinetics
Netupitant And Palonosetron
Absorption
Upon single oral administration of AKYNZEO capsules to
healthy subjects and patients, netupitant and palonosetron were measurable
within 1 hour after administration and reached the maximum concentration (Cmax)
in approximately 4 to 5 hours (Table 6).
Table 6: Systemic Exposure (AUCinf and Cmax) of
Netupitant and Palonosetron After a Single Oral Dose of AKYNZEO in Healthy
Subjects and Cancer Patients
Parameter |
Population |
Mean ( CV%2) |
Netupitant |
Palonosetron |
AUCmf (ng•h/mL) |
Healthy Subjects |
14,402 (51) |
56.7 (33) |
Patients |
17,365 (39) |
58.3 (50) |
Cmax (ng/mL) |
Healthy Subjects |
434 (56) |
1.53 (25) |
Patients |
496 (49) |
0.95 (35) |
tmax (h)1 |
Healthy Subjects |
5 (2 to 12) |
5 (1 to 12) |
Patients |
4 (2 to 8) |
5 (1 to 12) |
1 median (min-max);
2CV: coefficient of variation; AUCinf: area under the plasma concentration-time
curve from time 0 to infinity; tmax: time to maximum concentration. |
Following oral administration, the absolute
bioavailability of palonosetron was approximately 97%.
When AKYNZEO capsules were administered under fed
conditions, the systemic exposure to netupitant and palonosetron was similar to
the exposure under fasting conditions.
In cancer patients who received a single dose of AKYNZEO
capsules 1 hour prior to chemotherapy (docetaxel, etoposide, or
cyclophosphamide), the Cmax and the area under the concentration-time curve
from time zero to infinity (AUCinf ) of netupitant and its metabolites were
similar to those in healthy subjects. The mean Cmax and AUCinf of palonosetron
in cancer patients were similar to those in healthy subjects.
No changes in pharmacokinetics of netupitant and
palonosetron were observed when 450 mg oral netupitant and 0.75 mg oral
palonosetron were given alone or co-administered (1.5 times the recommended
dose of AKYNZEO capsules).
Dose Proportionality
Netupitant
There was a greater than dose-proportional increase in
the systemic exposure (108-fold AUCinf increase for a 30-fold dose increase)
when the oral netupitant dose was increased from 10 mg (approximately 3% the
recommended dose in AKYNZEO capsules) to 300 mg of netupitant and a
dose-proportional increase in the systemic exposure when the netupitant dose
was increased from 300 mg to 450 mg of netupitant (1.5 times the recommended
dose in AKYNZEO capsules).
Palonosetron
After single oral doses of palonosetron ranging from 0.25
to 6.8 mg (0.5 to 13.6 times the recommended dose in AKYNZEO capsules) using a
buffered solution, the mean Cmax and AUCinf were dose proportional in healthy
subjects.
Following single intravenous doses of AKYNZEO for
injection in patients or fosnetupitant in healthy subjects, Cmax of netupitant
and palonosetron were achieved at the end of the 30-minute infusion (Table 7).
Table 7: Systemic Exposure (AUC0-120 and Cmax) of
Netupitant and Palonosetron After a Single Intravenous Dose of AKYNZEO for
Injection in Cancer Patients or a Single Intravenous Dose of Fosnetupitant in
Healthy Subjects
Parameter |
Population |
Mean (CV%2) |
Netupitant |
Palonosetron |
AUC0-120 (ng•h/mL) |
Healthy Subjects |
12,012 (19) |
-- |
Patients |
8,922 (22) |
28 (28) |
Cmax (ng/mL) |
Healthy Subjects |
841 (21) |
-- |
Patients |
590 (28) |
0.8 (35) |
tmax (h)1 |
Healthy Subjects |
0.5 (0.5 to 0.4) |
-- |
Patients |
0.6 (0.5 to 4) |
0.6 (0.5 to 6) |
1 median (min-max);
2CV: coefficient of variation; AUC0-120: AUC from time 0 to 120
hours from start of infusion |
Distribution
After single oral administration of AKYNZEO capsules,
netupitant and palonosetron were widely distributed throughout the body (Table
8).
Table 8: Volume of Distribution (Vz/F) in Healthy
Subjects and Cancer Patients After a Single Oral Dose of AKYNZEO and In Vitro
Protein Binding
Parameter |
Population |
Mean (CV%c) |
Netupitant |
Palonosetron |
Vz/F (L) |
Healthy Subjects |
3314 (53) |
586 (33) |
Patients |
1982 (46) |
663 (24) |
Plasma Protein Binding |
In vitro studies |
Netupitant: > 99.5%a
Major Metabolites: > 97%b |
62% |
a Concentration range: 10 to 1300 ng/mL;
b Concentration range: 100 to 200 ng/mL;
cCV: coefficient of
variation |
After administration of single dose of AKYNZEO for
injection in patients, the mean ± SD of volume of distribution (Vz) of
netupitant and palonosetron were 2627 ± 990 L and 594 ± 239 L,
respectively, consistent with previous estimates after single oral
administration of AKYNZEO capsules in healthy subjects and cancer patients
(Table 8).
Elimination – Netupitant
After a single dose of AKYNZEO capsules, netupitant is
eliminated from the body in a multi-exponential fashion and the mean ± SD of
apparent elimination half-life was of 96 ± 59 hours in healthy subjects
and 80 ± 29 hours in cancer patients. The mean ± SD of estimated systemic
clearance (CL/F) was 26.3 ± 12.5 L/h in healthy subjects and 20.3 ± 9.2
L/h in patients.
In patients, following intravenous infusion of AKYNZEO
for injection, the mean ± SD total body clearance (CL) and terminal
half-life (t½) of netupitant were 14.1 ± 5.3 L/h and 144 ± 73
hours, respectively.
Metabolism
Once absorbed, netupitant is extensively metabolized to
form three major metabolites: desmethyl derivative, M1; N-oxide derivative, M2;
and OH-methyl derivative, M3. Metabolism is mediated primarily by CYP3A4 and to
a lesser extent by CYP2C9 and CYP2D6. Metabolites M1, M2 and M3 were shown to
bind to the substance P/neurokinin 1 (NK-1) receptor.
The mean AUCinf for metabolites M1, M2 and M3 was 29%,
14% and 33% of netupitant, respectively. The median tmax for metabolite M2 was
5 hours and was about 17 to 32 hours for metabolites M1 and M3, respectively.
Excretion
After a single oral administration of [14C]netupitant,
approximately half the administered radioactivity was recovered from urine and
feces within 120 hours of dosing. The total of 3.95% and 70.7% of the
radioactive dose was recovered in the urine and feces collected over 336 hours,
respectively, and the mean fraction of an oral dose of netupitant excreted
unchanged in urine is less than 1% suggesting renal clearance is not a
significant elimination route for the netupitant-related entities. About 86.5%
and 4.7% of administered radioactivity was estimated to be excreted via the
feces and urine within 30 days post-dose.
Elimination -Palonosetron
Following oral administration of AKYNZEO capsules in
healthy subjects and cancer patients, the mean ( ± SD) of half-life of
palonosetron was 44 ± 15 hours and 50 ± 16 hours, respectively, whereas
the mean ± SD of total body clearance (CL/F) was 9.6 ± 2.7 L/h
and 10.0 ± 3.4 L/h, respectively.
After a single intravenous palonosetron dose of 10 mcg/kg
(approximately 3 times the recommended dose in AKYNZEO for injection), the mean
± SD of total body clearance (CL) of palonosetron in healthy subjects was 12.1
± 3.7 L/h, and renal clearance (CLR) was 5.1 ± 2.1 L/h.
In patients, following intravenous infusion of AKYNZEO
for injection, the mean ± SD total body clearance (CL) and terminal
half-life (t½) of palonosetron were 7.6 ± 2.6 L/h and 58 ± 27
h, respectively.
Metabolism
Palonosetron is eliminated by multiple routes with
approximately 50% metabolized to form two primary metabolites:
N-oxide-palonosetron and 6-Shydroxy-palonosetron. These metabolites each have
less than 1% of the 5-HT3 receptor antagonist activity of palonosetron. In
vitro metabolism studies have suggested that CYP2D6 and to a lesser extent
CYP3A4 and CYP1A2 are involved in the metabolism of palonosetron. However,
clinical pharmacokinetic parameters such as Cmax, AUCinf, CL, CLR, Vz and t½ are
not significantly different between poor and extensive metabolizers of CYP2D6
substrates.
Excretion
Following administration of a single oral 0.75 mg dose of
[14C]palonosetron (1.5 times the recommended dose in AZKYNZEO
capsules) to six healthy subjects, 85% to 93% of the total radioactivity was
excreted in urine, and 5% to 8% was eliminated in feces. The amount of
unchanged palonosetron excreted in the urine represented approximately 40% of
the administered dose.
Fosnetupitant
Absorption
Following single intravenous doses of AKYNZEO for
injection in patients (235 mg fosnetupitant and 0.25 mg palonosetron infused in
30 minutes) or fosnetupitant in healthy subjects (235 mg fosnetupitant infused
in 30 minutes), maximum concentrations of fosnetupitant were achieved at the end
of the 30-minute infusion (Table 9).
Table 9: Systemic Exposure of Fosnetupitant After a
Single Intravenous Dose of Fosnetupitant in Healthy Subjects or AKYNZEO for
Injection in Cancer Patients
Parameter |
Population |
Mean (CV%2) |
Cmax (ng/mL) |
Healthy Subjects |
6431 (14) |
Patients |
3478 (45) |
tmax1 (h) |
Healthy Subjects |
0.5 (0.25 to 0.5) |
Patients |
0.5 (0.5 to 0.6) |
AUCinf (ng•h/mL) |
Healthy Subjects |
2938 (12) |
Patients |
1401 (46) |
1 median (min-max);
2CV: coefficient of variation; AUCinf: AUC from time 0 to infinity |
In cross-study comparisons, the mean Cmax and AUCinf of
fosnetupitant were lower in patients than in healthy subjects. Similarly, AUC0-120
and Cmax of netupitant in patients were 26% and 30% lower than in healthy
subjects, respectively (Table 7). The differences in systemic exposures to
netupitant are clinically insignificant.
In healthy subjects, there was a dose-proportional
increase in the systemic exposure when the dose of fosnetupitant was increased
from 17.6 mg (7.5% of recommended dose in AKYNZEO for injection) to 353 mg
(150% of recommended dose in AKYNZEO for injection).
Distribution
The mean ± SD volume of distribution (Vz) of
fosnetupitant in healthy subjects and in patients was 124 ± 76 L and 296
±535 L, respectively. The human plasma protein binding of fosnetupitant
was 92% at 1 micromolar and 95% at 10 micromolar.
Elimination
After intravenous administration of AKYNZEO for
injection, fosnetupitant plasma concentrations declined in a biexponential
manner. Thirty minutes after the end of the infusion, the mean plasma
concentration of fosnetupitant was less than 1% of Cmax.
The mean ± SD of terminal elimination half-life
and systemic plasma clearance (CL) of fosnetupitant were respectively 0.75
± 0.40 hours and 249 ± 270 L/h in cancer patients after a single
IV dose of AKYNZEO. They were 0.96 ± 0.55 hours (mean ± SD) and
90 ± 13 L/h in healthy subjects after a single intravenous dose of
fosnetupitant.
Metabolism
Fosnetupitant is converted in vivo to netupitant by
metabolic hydrolysis. In patients receiving AKYNZEO intravenously, netupitant
exposure was 17-fold fosnetupitant exposure, as determined by their AUCinf ratio.
Netupitant metabolites M1, M2 and M3 were generated from the released
netupitant. In patients, metabolite M1, M2 and M3 exposures were 32%, 21% and
28% of netupitant exposure. The median tmax for M1, M2, and M3 were 12, 2 and
12 hours, respectively.
Specific Populations
Geriatric Patients
In cancer patients receiving AKYNZEO capsules, population
pharmacokinetic analysis indicated that age (within the range of 29 to 75
years) did not influence the pharmacokinetics of netupitant or palonosetron. In
healthy elderly subjects (greater than 65 years of age) the mean AUCinf and Cmax
was 25% and 36% higher, respectively, for netupitant, and 37% and 10% higher,
respectively, for palonosetron compared to those in healthy younger adults (22
to 45 years of age). The increase in the systemic exposure to netupitant in the
elderly subjects is not considered to be clinically significant.
Male And Female Patients
In a pooled analysis of data following AKYNZEO capsules,
the Cmax for netupitant was 35% higher in females than in males while the AUCinf
was similar between males and females. In female subjects, the mean AUCinf for
palonosetron was 35% higher and the mean Cmax was 26% higher than in male
subjects. Sex did not affect the pharmacokinetics of fosnetupitant, netupitant,
netupitant metabolites and palonosetron after a single intravenous dose of
AKYNZEO in patients. In healthy subjects, no effect of sex was observed on the pharmacokinetics
of fosnetupitant, netupitant and its metabolites after a single intravenous
dose of fosnetupitant alone. The mean ± SD of netupitant AUCinf and Cmax
in patients were 15672 ± 5496 ng•h/mL and 567 ± 174 ng/mL,
respectively in males and 15518 ± 4814 ng•h/mL and 609 ±
161 ng/mL, respectively in females.
Patients With Renal Impairment
Population pharmacokinetic analysis showed that mild and
moderate renal impairment (creatinine clearance 30 to 60 mL/min) did not
significantly affect the pharmacokinetics of netupitant in cancer patients.
Netupitant has not been studied in patients with severe renal impairment
(creatinine clearance less than 30 mL/min).
Mild to moderate renal impairment does not significantly
affect palonosetron pharmacokinetic parameters. In a study with intravenous
palonosetron, total systemic exposure to palonosetron increased by
approximately 28% in patients with severe renal impairment relative to healthy
subjects.
The pharmacokinetics of palonosetron and netupitant have
not been studied in subjects with end-stage renal disease (creatinine clearance
< 15 mL/min not on dialysis) [see Use In Specific Populations].
Patients With Hepatic Impairment
The effects of hepatic impairment on the pharmacokinetics
of netupitant and palonosetron were studied following administration of a
single oral dose of AKYNZEO to patients with mild (Child-Pugh score 5 to 6),
moderate (Child-Pugh score 7 to 9), or severe (Child-Pugh score >9) hepatic
impairment.
In patients with mild or moderate hepatic impairment, the
mean AUCinf of netupitant was 67% and 86% higher, respectively, than in healthy
subjects and the mean Cmax for netupitant was about 40% and 41% higher,
respectively, than in healthy subjects.
In patients with mild or moderate hepatic impairment, the
mean AUCinf of palonosetron was 33% and 62% higher, respectively, than in
healthy subjects and the mean Cmax for palonosetron was about 14% higher and
unchanged, respectively, than in healthy subjects.
The pharmacokinetics of netupitant and palonosetron were
available from only two patients with severe hepatic impairment. As such the
data are too limited to draw a conclusion [see Use In Specific Populations].
Drug Interaction Studies
Effect Of Netupitant/Fosnetupitant And/Or Palonosetron On
Other Drugs
CYP3A4
In vitro studies have shown that netupitant and its
metabolite M1 are inhibitors of CYP3A4. An in vivo study has confirmed that
netupitant is a moderate inhibitor of CYP3A4.
Dexamethasone
In healthy subjects, the oral administration of a single
AKYNZEO capsule with the CYP3A4 substrate dexamethasone (12 mg on day 1
followed by once-a-day administrations of 8 mg on days 2, 3, 4, 6, 8 and 10),
increased the plasma concentrations of dexamethasone for 6 days (Table 10).
Table 10: Effect of a Single Dose of Oral AKYNZEO (Day
1) on the Systemic Exposure of a Co-administered CYP3A4 Substrate
(Dexamethasone) in Healthy Subjects
% Change for Dexamethasone |
Day 1 |
Day 4 |
Day 6 |
Day 8 |
Cmax |
AUC0-t |
Cmax |
AUC0-t |
Cmax |
AUC0-t |
Cmax |
AUC0-t |
2%↓ |
58%↑ |
54%↑ |
139%↑ |
29%↑ |
49%t |
7%↑ |
20%↑ |
*the interacting drug (dexamethasone 12 mg) was
administered on day 1 with AKYNZEO and alone (8 mg) on days 2, 3, 4, 6, 8 and
10; AUC0-t: AUC from time zero to time t of last measurable concentration after
dexamethasone administration on Days 1, 4, 6 and 8
↑ = Increased; ↓ = Decreased |
In healthy subjects, co-administration of a single
intravenous fosnetupitant dose (235 mg) with a 20 mg oral dexamethasone on day
1 followed by twice-a-day administrations of 8 mg dexamethasone on days 2, 3,
and 4, increased dexamethasone exposure 2.4-fold on day 4 (Table 11).
Table 11: Effect of a Single 235 mg Dose of
Intravenous Fosnetupitant (Day 1) on the Systemic Exposure of a Co-administered
CYP3A4 Substrate (Dexamethasone) in Healthy Subjects
% Change for Dexamethasone |
Day 1 |
Day 4 |
Cmax |
AUC0-24 |
Cmax |
AUC84-108 |
3%↓ |
50%↑ |
70%↑ |
142%↑ |
*the interacting drug (dexamethasone 20 mg) was
administered on day 1 with AKYNZEO and alone (8 mg bid) on Days 2,3,4; AUC0-24:
AUC from time 0 to 24h after dexamethasone administration on Day 1; AUC84-108:
AUC from time 84h to 108h after dexamethasone administration on Day 4
↑ = Increased; ↓ = Decreased |
Considering the limited fosnetupitant exposure in human
plasma and its conversion to netupitant within 30 minutes after completion of
infusion, the effects are ascribed to netupitant [see DRUG INTERACTIONS].
Midazolam
When co-administered with netupitant 300 mg the mean Cmax
and AUCinf of midazolam after single dose oral administration of 7.5 mg
midazolam was 36% and 126% higher, respectively [see DRUG INTERACTIONS].
Chemotherapeutic Agents (docetaxel, etoposide,
cyclophosphamide)
Systemic exposure to intravenously administered
chemotherapeutic agents that are metabolized by CYP3A4 was higher when AKYNZEO
capsules was co-administered in cancer patients than when palonosetron alone
was co-administered (see Table 12).
Table 12: Effect of a Single Dose of Oral AKYNZEO on
the Systemic Exposure of Co-administered Chemotherapy Agents Metabolized by
CYP3A4 in Patients with Cancer
Co-administered Chemotherapeutic Agenta |
Change in Systemic Exposures of Chemotherapeutic Agents when Co-administered with AKYNZEO Capsules Compared to Coadministration with Palonosetron |
AUC0-tb |
Cmax |
Docetaxel 75 to 100 mg/m² |
35%↑ |
49%↑ |
Etoposide 35 to 100 mg/m² |
28%↑ |
10%↑ |
Cyclophosphamide 500 to 1000 mg/m² |
20%↑ |
27%↑ |
a Following a single oral dose of AKYNZEO
compared to co-administered with palonosetron alone
bAUC0-t: AUC from time zero to time t of last measurable
concentration
↑ = Increased; ↓ = Decreased |
The mean AUCinf of palonosetron was about 65% higher when
AKYNZEO capsules was co-administered with docetaxel than with etoposide or
cyclophosphamide, while the mean AUCinf of netupitant was similar among groups
that received docetaxel, etoposide, or cyclophosphamide [see DRUG
INTERACTIONS].
Erythromycin
When 500 mg erythromycin was co-administered with
netupitant 300 mg, the systemic exposure of erythromycin was highly variable and
the mean Cmax and AUCinf of erythromycin were increased by 92% and 56%,
respectively. The change in exposure is not clinically significant.
Oral Contraceptives
A single dose of AKYNZEO capsules, when given with a
single oral dose of 60 mcg ethinyl estradiol and 300 mcg levonorgestrel, showed
no effect on Cmax and increased the AUC0-t of levonorgestrel by 46%. The Cmax
and AUC0-t of ethinyl estradiol increased by 5% and 16% respectively. The
change in exposure is not clinically significant [see DRUG INTERACTIONS].
Other CYP P450 Enzymes
Based on the in vitro studies, netupitant, and its
metabolites are unlikely to have in vivo drug-drug interaction via inhibition
of CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, and CYP2D6 at the clinical dose of
oral AKYNZEO.
Netupitant and its metabolites, M1, M2 and M3, are not
inducers of CYP1A2, CYP2B6, CYP2C9, CYP2C19 and CYP3A4.
In in vitro studies, palonosetron did not inhibit CYP1A2,
CYP2A6, CYP2B6, CYP2C9, CYP2D6, CYP2E1 and CYP3A4/5 or induce CYP1A2, CYP2D6 or
CYP3A4/5. CYP2C19 was not investigated.
Transporters – P-gp And BCRP
Based on in vitro studies, netupitant is an inhibitor of
P-glycoprotein (P-gp) and breast cancer resistant protein (BCRP) transporters. In
vitro studies indicated that fosnetupitant is an inhibitor of P-gp. However, an
in vivo interaction between AKYNZEO for injection and P-gp substrates is
considered unlikely.
In vitro, palonosetron was an inhibitor of MATE1,
MATE2-K, OCT1, OCT2 and OAT3 transporters. An in vivo interaction between
AKYNZEO capsules or injection and transporter substrates is considered
unlikely.
Digoxin –P-gp Substrate
Co-administration of oral netupitant 450 mg (1.5 times
the recommended dose in AKYNZEO capsules) did not significantly affect the
systemic exposure (4% increase of AUC0-24 at steady state) and urinary
excretion (2% increase) of oral digoxin, a substrate of P-gp, at steady-state.
Concurrent administration of AKYNZEO capsules or AKYNZEO for injection with
digoxin is not expected to affect the systemic exposure to digoxin.
Other Transporters
In vitro studies indicate that netupitant and its three
major metabolites are unlikely to have in vivo drug-drug interactions with
human efflux transporters BSEP, MRP2, and human uptake transporters OATP1B1,
OATP1B3, OAT1, OAT3, OCT1, and OCT2 at the clinical dose of 300 mg.
In vitro studies indicated that fosnetupitant is an
inhibitor of OATP1B1 and OATP1B3 transporters. However, an in vivo interaction
between AKYNZEO for injection and OATP1B1, OATP1B3, and P-gp substrates is
considered unlikely.
Effects Of Other Drugs On Netupitant/Fosnetupitant And/Or
Palonosetron
Netupitant is not a substrate for P-gp. However,
metabolite M2 is a substrate for P-gp.
Netupitant and palonosetron are CYP3A4 substrates.
Co-administration of strong CYP3A4 inhibitors, such as ketoconazole, or strong
CYP3A4 inducers, such as rifampin, with a single oral administration of AKYNZEO
capsules affects with clinical significance the exposure to netupitant but not
to palonosetron (Table 13).
Table 13: Change in Systemic Exposure to Netupitant
and Palonosetrona When a Single Dose of AKYNZEO is Co-Administered with Either
a CYP3A4 Inhibitor or a CYP3A4 Inducer in Healthy Subjects
Co-administered Drug |
Netupitantb |
Palonosetronb |
AUCinf |
Cmax |
AUCinf |
Cmax |
Strong CYP3A4 Inhibitor |
Ketoconazole 400 mg once daily for 12 days |
140%↑ |
25%↑ |
10%↑ |
15%↑ |
Strong CYP3A4 Inducer |
Rifampin 600 mg once daily for 17 days |
62% ↓ |
82% ↓ |
19%↓ |
15%↓ |
a Following a single oral dose of AKYNZEO;
b Geometric Mean AUCinf and Cmax;
↑ = Increased; ↓ = Decreased |
Clinical Studies
Study 1
In a multicenter, randomized, parallel, double-blind,
controlled clinical trial of 694 patients, the efficacy and safety of a single
dose of oral netupitant in combination with oral palonosetron was compared with
a single oral dose of palonosetron in cancer patients receiving a chemotherapy
regimen that included cisplatin (median dose of 75 mg/m²). The efficacy of
AKYNZEO was assessed in 135 patients who received AKYNZEO capsules (300 mg
netupitant and 0.5 mg palonosetron) and 136 patients who received oral
palonosetron 0.5 mg.
Treatment regimens for the AKYNZEO and palonosetron arms
are summarized in Table 14.
Table 14: Oral Antiemetic Treatment Regimen in Study 1
Treatment Regimen |
Day 1 |
Days 2 to 4 |
AKYNZEO |
AKYNZEO capsules: 300 mg neupitant/ 0.5 mg palonosetron Dexamethasone 12 mg |
Dexamethasone 8 mg once a day |
Palonosetron |
Palonosetron 0.5 mg Dexamethasone 20 mg |
Dexamethasone 8 mg twice a day |
Of the 135 patients who received AKYNZEO, 43% were women,
and all patients were White. The age ranged from 19 to 77 years, with a median
age of 53 years.
During the study, 86% of the 135 treated patients in the
AKYNZEO arm received a concomitant chemotherapeutic agent in addition to
protocol-mandated cisplatin. The most common chemotherapeutic agents and the
proportion of patients exposed were cyclophosphamide (34%), fluorouracil (24%),
etoposide (21%), and doxorubicin (16%).
The key efficacy endpoints were complete response (CR)
(defined as no emetic episode and no use of rescue medication) for the 25 to
120 hour interval (delayed phase), CR for the 0 to 24 hour interval (acute
phase), and CR within 120 hours (overall phase) after the start of the
chemotherapy administration.
A summary of the key results from this study is shown in
Table 15.
Table 15: Proportion of Patients Responding by
Treatment Group and Phase in Study 1
|
AKYNZEO Capsules 300 mg netupitant/ 0.5 mg palonosetron
N=135 % |
Palonosetron 0.5 mg
N=136 % |
p-value* |
COMPLETE RESPONSE |
Delayed Phase† |
90.4 |
80.1 |
0.032 |
Acute Phase‡ |
98.5 |
89.7 |
0.002 |
Overall Phase§ |
89.6 |
76.5 |
0.003 |
*Adjusted p-values for multiple comparisons using
Cochran-Mantel-Haenszel test, stratified by gender.
†Delayed phase: 25 to 120 hours post-cisplatin treatment.
‡Acute phase: 0 to 24 hours post-cisplatin treatment.
§Overall: 0 to 120 hours post-cisplatin treatment. |
Study 2 (NCT01339260)
In a multicenter, randomized, parallel, double-blind,
active controlled, superiority trial, the efficacy and safety of a single oral
dose of AKYNZEO was compared with a single oral dose of palonosetron 0.5 mg in
cancer patients scheduled to receive the first cycle of an anthracycline and
cyclophosphamide (AC) regimen for the treatment of a solid malignant tumor
(Study 2). All patients received a single oral dose of dexamethasone. Treatment
regimens for the AKYNZEO and palonosetron arms are summarized in Table 16.
Table 16: Oral Antiemetic Treatment Regimen in Study 2
Treatment Regimen |
Day 1 |
Days 2 to 3 |
AKYNZEO |
AKYNZEO capsules: 300 mg netupitant/ 0.5 mg palonosetron Dexamethasone 12 mg |
No antiemetic treatment |
Palonosetron |
Palonosetron 0.5 mg Dexamethasone 20 mg |
No antiemetic treatment |
After completion of cycle 1, patients had the option to
participate in a multiple-cycle extension, receiving the same treatment as
assigned in cycle 1. There was no pre-specified limit of the number of repeat
consecutive cycles for any patient.
A total of 1455 patients were randomized to the AKYNZEO
arm or palonosetron arm. A total of 1450 patients (AKYNZEO n=725; palonosetron
n=725) received study medication: of these, 1438 patients (99%) completed cycle
1 and 1286 patients (88%) continued treatment in the multiple-cycle extension.
A total of 907 patients (62%) completed the multiple-cycle extension up to a
maximum of eight treatment cycles.
Of the 725 patients who received AKYNZEO, 711 (98%) were
women; 79% were White, 14% Asian, 6% Hispanic, and <1% were Black or Other.
Age ranged from 22 to 79 years, with a median age of 54 years. A total of 724
patients (99.9%) were treated with cyclophosphamide. All patients were
additionally treated with either doxorubicin (68%) or epirubicin (32%).
During the first cycle, 32% of the 725 patients treated
with AKYNZEO received a concomitant chemotherapeutic agent in addition to
protocol-mandated regimens, with the most common chemotherapeutic being
fluorouracil (28%) and docetaxel (3%).
The primary efficacy endpoint was the CR rate in the
delayed phase, 25 to120 hours after the start of chemotherapy administration.
Major secondary efficacy endpoints included CR for the
acute and overall phases. A summary of key results from Study 2 is shown in
Table 17.
Table 17: Proportion of Patients Responding by Treatment
Group and Phase – Cycle 1 in Study 2
|
AKYNZEO Capsules 300 mg netupitant/ 0.5 mg palonosetron
N=724 % |
Palonosetron 0.5 mg
N=725 % |
p-value* |
PRIMARY ENDPOINT |
COMPLETE RESPONSE |
Delayed Phase† |
76.9 |
69.5 |
0.001 |
MAJOR SECONDARY ENDPOINTS |
COMPLETE RESPONSE |
Acute Phase‡ |
88.4 |
85.0 |
0.047 |
Overall Phase§ |
74.3 |
66.6 |
0.001 |
*p-value from Cochran-Mantel-Haenszel test, stratified by
age class and region.
‡Acute phase: 0 to 24 hours after anthracycline and cyclophosphamide regimen.
†Delayed phase: 25 to 120 hours after anthracycline and cyclophosphamide
regimen.
§Overall: 0 to 120 hours after anthracycline and cyclophosphamide regimen. |
Multiple Cycles
Patients continued into the Multiple-Cycle extension for
up to 7 additional cycles of chemotherapy. The proportion of patients with
complete response in the delayed phase by treatment group at each cycle (cycles
2 to 6) is displayed in Figure 1. A limited number of patients received
treatment beyond cycle 6. During all cycles the CR rate in the delayed phase
was higher for AKYNZEO than for palonosetron. Antiemetic activity of AKYNZEO
was maintained throughout repeat cycles for those patients continuing in each
of the multiple cycles.
Figure 1: Proportion of Patients with Complete
Response in the Delayed Phase by Treatment Group and Cycle in Study 2
Additional clinical trials (Study 3 and Study 4) were
conducted to support the efficacy of AKYNZEO.
Study 3 (NCT01376297)
In a separate study, 309 patients undergoing initial and
repeat cycles of chemotherapy (including carboplatin, cisplatin, oxaliplatin,
and doxorubicin regimens) received AKYNZEO; efficacy was maintained throughout
all cycles.
Study 4 (NCT01363479)
In a multicenter, multinational, randomized,
active-controlled, double-blind, double-dummy, parallel group, clinical
non-inferiority study, the efficacy and safety of a single dose of oral
palonosetron 0.5 mg was compared to intravenous palonosetron 0.25 mg in cancer
patients scheduled to receive highly emetogenic cisplatin (>70 mg/m²) based
chemotherapy. The purpose of this study was to demonstrate that oral
palonosetron 0.5 mg contributes to the efficacy of AKYNZEO during the acute
phase (first 24 hours after cancer chemotherapy) in the setting of cisplatin
based chemotherapy. A total of 739 patients (oral palonosetron n=370;
intravenous palonosetron n=369) received study medication.
The primary efficacy endpoint was complete response (CR)
(defined as no emetic episode and no use of rescue medication) within 24 hours
(acute phase) after the start of cisplatin-based chemotherapy administration.
In the oral palonosetron arm, 89.4% of patients achieved a CR in the acute
phase compared to 86.2% of patients in the intravenous palonosetron arm, with a
difference of 3.2% (99% CI: -2.7% to 9.2%). Non-inferiority of oral
palonosetron versus intravenous palonosetron was demonstrated since the lower
limit of the two-sided 99% CI for the difference in proportions of patients
with CR was greater (i.e., closer to zero) than the pre-defined non-inferiority
margin set at -15%.
Study 5 (NCT02557035)
In a multicenter, multinational, randomized, active
controlled, double blind, double dummy, parallel group, clinical
non-inferiority study, the efficacy and safety of a single dose of intravenous
palonosetron 0.25 mg administered over 30 minutes (infusion) was compared to
intravenous palonosetron 0.25 mg administered over 30 seconds (bolus) in cancer
patients scheduled to receive a HEC chemotherapy regimen that included
cisplatin administered as a single IV dose of 70 mg/m², cyclophosphamide 1500
mg/m², carmustine (BCNU) >250mg/m², dacarbazine (DTIC) and mechloretamine
(nitrogen mustard). The purpose of this study was to demonstrate that
intravenous palonosetron 0.25 mg administered over 30 minutes was non-inferior
to administration of intravenous palonosetron 0.25 mg administered over 30
seconds for prevention of nausea and vomiting during the acute phase (first 24
hours after cancer chemotherapy) in the HEC setting. A total of 425 patients
(intravenous palonosetron infusion n=214; intravenous palonosetron bolus n=211)
received study medication and HEC and completed the 0-24 h study period with no
major protocol violations and were included in the Per Protocol Population.
The primary efficacy endpoint was complete response (CR defined
as no emetic episode and no use of rescue medication) in the 24 hours (acute
phase) after the start of the scheduled chemotherapy. In the intravenous
palonosetron infusion group, 82.7% of patients achieved CR in the acute phase
compared to 86.3% of patients in the intravenous palonosetron bolus group, with
a difference of -3.4% (99% CI: -12.0% to 5.2%). Non-inferiority of
administration of intravenous palonosetron over 30 minutes compared to
administration of intravenous palonosetron over 30 seconds was demonstrated
since the lower limit of the two-sided 99% CI for the difference in proportions
of patients with CR was greater (i.e., closer to zero) than the pre-defined non
inferiority margin set at -15%.