Mechanism of Action
Aprepitant is a selective high-affinity antagonist of human
substance P/neurokinin 1 (NK1) receptors. Aprepitant has little or no affinity
for serotonin (5-HT3), dopamine, and corticosteroid receptors, the targets of
existing therapies for chemotherapy-induced nausea and vomiting (CINV) and
postoperative nausea and vomiting (PONV).
Aprepitant has been shown in animal models to inhibit emesis
induced by cytotoxic chemotherapeutic agents, such as cisplatin, via central
actions. Animal and human Positron Emission Tomography (PET) studies with
aprepitant have shown that it crosses the blood brain barrier and occupies
brain NK1 receptors. Animal and human studies show that aprepitant augments the
antiemetic activity of the 5-HT3receptor antagonist ondansetron and the
corticosteroid dexamethasone and inhibits both the acute and delayed phases of
cisplatin-induced emesis.
Pharmacokinetics
Absorption
Following oral administration of a single 40 mg dose of
EMEND in the fasted state, mean area under the plasma concentration-time curve
(AUC0-∞) was 7.8 mcg•hr/mL and mean peak plasma concentration (Cmax) was
0.7 mcg/mL, occurring at approximately 3 hours postdose (Tmax). The absolute
bioavailability at the 40-mg dose has not been determined.
Following oral administration of a single 125-mg dose of EMEND on Day 1 and
80 mg once daily on Days 2 and 3, the AUC0-24hr was approximately 19.6 mcg•hr/mL
and 21.2 mcg•hr/mL on Day 1 and Day 3, respectively. The Cmax of 1.6 mcg/mL
and 1.4 mcg/mL were reached in approximately 4 hours (Tmax) on Day 1 and Day
3, respectively. At the dose range of 80-125 mg, the mean absolute oral bioavailability
of aprepitant is approximately 60 to 65%. Oral administration of the capsule
with a standard high-fat breakfast had no clinically meaningful effect on the
bioavailability of aprepitant.
The pharmacokinetics of aprepitant are non-linear across the
clinical dose range. In healthy young adults, the increase in AUC0-∞ was
26% greater than dose proportional between 80-mg and 125-mg single doses
administered in the fed state.
Distribution
Aprepitant is greater than 95% bound to plasma proteins. The
mean apparent volume of distribution at steady state (Vdss) is approximately 70
L in humans.
Aprepitant crosses the placenta in rats and rabbits and
crosses the blood brain barrier in humans (see CLINICAL PHARMACOLOGY,
Mechanism of Action).
Metabolism
Aprepitant undergoes extensive metabolism. In vitro studies
using human liver microsomes indicate that aprepitant is metabolized primarily
by CYP3A4 with minor metabolism by CYP1A2 and CYP2C19. Metabolism is largely
via oxidation at the morpholine ring and its side chains. No metabolism by
CYP2D6, CYP2C9, or CYP2E1 was detected. In healthy young adults, aprepitant
accounts for approximately 24% of the radioactivity in plasma over 72 hours
following a single oral 300-mg dose of [14C]-aprepitant, indicating
a substantial presence of metabolites in the plasma. Seven metabolites of
aprepitant, which are only weakly active, have been identified in human plasma.
Excretion
Following administration of a single IV 100-mg dose of [14C]-aprepitant
prodrug to healthy subjects, 57% of the radioactivity was recovered in urine
and 45% in feces. A study was not conducted with radiolabeled capsule
formulation. The results after oral administration may differ.
Aprepitant is eliminated primarily by metabolism; aprepitant
is not renally excreted. The apparent plasma clearance of aprepitant ranged
from approximately 62 to 90 mL/min. The apparent terminal half-life ranged from
approximately 9 to 13 hours.
Special Populations
Gender
Following oral administration of a single 125-mg dose of
EMEND, no difference in AUC0-24hr was observed between males and females. The
Cmax for aprepitant is 16% higher in females as compared with males. The
half-life of aprepitant is 25% lower in females as compared with males and Tmax
occurs at approximately the same time. These differences are not considered
clinically meaningful. No dosage adjustment for EMEND is necessary based on
gender.
Geriatric
Following oral administration of a single 125-mg dose of
EMEND on Day 1 and 80 mg once daily on Days 2 through 5, the AUC0-24hr of
aprepitant was 21% higher on Day 1 and 36% higher on Day 5 in elderly
( ≥ 65 years) relative to younger adults. The Cmax was 10% higher on Day 1 and
24% higher on Day 5 in elderly relative to younger adults. These differences
are not considered clinically meaningful. No dosage adjustment for EMEND is
necessary in elderly patients.
Pediatric
The pharmacokinetics of EMEND have not been evaluated in
patients below 18 years of age.
Race
Following oral administration of a single 125-mg dose of
EMEND, the AUC0-24hr is approximately 25% and 29% higher in Hispanics as
compared with Whites and Blacks, respectively. The Cmax is 22% and 31% higher
in Hispanics as compared with Whites and Blacks, respectively. These
differences are not considered clinically meaningful. There was no difference
in AUC0-24hr or Cmax between Whites and Blacks. No dosage adjustment for EMEND
is necessary based on race.
Hepatic Insufficiency
EMEND was well tolerated in patients with mild to moderate
hepatic insufficiency. Following administration of a single 125-mg dose of
EMEND on Day 1 and 80 mg once daily on Days 2 and 3 to patients with mild
hepatic insufficiency (Child-Pugh score 5 to 6), the AUC0-24hr of aprepitant
was 11% lower on Day 1 and 36% lower on Day 3, as compared with healthy
subjects given the same regimen. In patients with moderate hepatic
insufficiency (Child-Pugh score 7 to 9), the AUC0-24hr of aprepitant was 10%
higher on Day 1 and 18% higher on Day 3, as compared with healthy subjects
given the same regimen. These differences in AUC0-24hr are not considered
clinically meaningful; therefore, no dosage adjustment for EMEND is necessary
in patients with mild to moderate hepatic insufficiency.
There are no clinical or pharmacokinetic data in patients
with severe hepatic insufficiency (Child-Pugh score > 9) (see PRECAUTIONS).
Renal Insufficiency
A single 240-mg dose of EMEND was administered to patients
with severe renal insufficiency (CrCl < 30 mL/min) and to patients with end
stage renal disease (ESRD) requiring hemodialysis.
In patients with severe renal insufficiency, the
AUC0-∞ of total aprepitant (unbound and protein bound) decreased by 21%
and Cmax decreased by 32%, relative to healthy subjects. In patients with ESRD
undergoing hemodialysis, the AUC0-∞ of total aprepitant decreased by 42%
and Cmax decreased by 32%. Due to modest decreases in protein binding of
aprepitant in patients with renal disease, the AUC of pharmacologically active
unbound drug was not significantly affected in patients with renal
insufficiency compared with healthy subjects. Hemodialysis conducted 4 or 48
hours after dosing had no significant effect on the pharmacokinetics of
aprepitant; less than 0.2% of the dose was recovered in the dialysate.
No dosage adjustment for EMEND is necessary for patients
with renal insufficiency or for patients with ESRD undergoing hemodialysis.
Clinical Studies
Prevention of Chemotherapy Induced Nausea and Vomiting
Oral administration of EMEND in combination with ondansetron
and dexamethasone (aprepitant regimen) has been shown to prevent acute and
delayed nausea and vomiting associated with highly emetogenic chemotherapy
including high-dose cisplatin, and nausea and vomiting associated with
moderately emetogenic chemotherapy.
Highly Emetogenic Chemotherapy
In 2 multicenter, randomized, parallel, double-blind,
controlled clinical studies, the aprepitant regimen (see table below) was
compared with standard therapy in patients receiving a chemotherapy regimen
that included cisplatin > 50 mg/m² (mean cisplatin dose = 80.2 mg/m²). Of the
550 patients who were randomized to receive the aprepitant regimen, 42% were
women, 58% men, 59% White, 3% Asian, 5% Black, 12% Hispanic American, and 21%
Multi-Racial. The aprepitant-treated patients in these clinical studies ranged
from 14 to 84 years of age, with a mean age of 56 years. 170 patients were 65
years or older, with 29 patients being 75 years or older.
Patients (N = 1105) were randomized to either the aprepitant
regimen (N = 550) or standard therapy (N = 555). The treatment regimens are
defined in the table below.
Treatment Regimens Highly Emetogenic Chemotherapy Trials
| Treatment Regimen |
Day 1 |
Days 2 to 4 |
| Aprepitant |
Aprepitant 125 mg PO
Dexamethasone 12 mg
PO Ondansetron 32 mg IV |
Aprepitant 80 mg PO Daily (Days 2 and 3 only)
Dexamethasone 8 mg PO Daily (morning) |
| Standard Therapy |
Dexamethasone 20 mg
PO Ondansetron 32 mg IV |
Dexamethasone 8 mg PO Daily (morning)
Dexamethasone 8 mg PO Daily (evening) |
| Aprepitant placebo and dexamethasone placebo were used to
maintain blinding. |
During these studies 95% of the patients in the aprepitant group received a
concomitant chemotherapeutic agent in addition to protocol-mandated cisplatin.
The most common chemotherapeutic agents and the number of aprepitant patients
exposed follows: etoposide (106), fluorouracil (100), gemcitabine (89), vinorelbine
(82), paclitaxel (52), cyclophosphamide (50), doxorubicin (38), docetaxel (11).
The antiemetic activity of EMEND was evaluated during the
acute phase (0 to 24 hours post-cisplatin treatment), the delayed phase (25 to
120 hours post-cisplatin treatment) and overall (0 to 120 hours postcisplatin
treatment) in Cycle 1. Efficacy was based on evaluation of the following
endpoints: Primary endpoint:
- complete response (defined as no emetic episodes and no use of rescue therapy)
Other prespecified endpoints:
- complete protection (defined as no emetic episodes, no use of rescue therapy,
and a maximum nausea visual analogue scale [VAS] score < 25 mm on a 0 to
100 mm scale)
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
- no nausea (maximum VAS < 5 mm on a 0 to 100 mm scale)
- no significant nausea (maximum VAS < 25 mm on a 0 to 100 mm scale)
A summary of the key study results from each individual
study analysis is shown in Table 1 and in Table 2.
Table 1 : Percent of Patients Receiving Highly Emetogenic
Chemotherapy Responding by Treatment Group and Phase for Study 1 — Cycle 1
| ENDPOINTS |
Aprepitant
Regimen
(N = 260)†
% |
Standard
Therapy
(N = 261) †
% |
p-Value |
| PRIMARY ENDPOINT |
| Complete Response |
| Overall‡ |
73 |
52 |
< 0.001 |
| OTHER PRESPECIFIED ENDPOINTS |
| Complete Response |
| Acute phase§ |
89 |
78 |
< 0.001 |
| Delayed phase|| |
75 |
56 |
< 0.001 |
| Complete Protection |
|
|
|
| Overall |
63 |
49 |
0.001 |
| Acute phase |
85 |
75 |
NS* |
| Delayed phase |
66 |
52 |
< 0.001 |
| No Emesis |
| Overall |
78 |
55 |
< 0.001 |
| Acute phase |
90 |
79 |
0.001 |
| Delayed phase |
81 |
59 |
< 0.001 |
| No Nausea |
| Overall |
48 |
44 |
NS** |
| Delayed phase |
51 |
48 |
NS** |
| No Significant Nausea |
| Overall |
73 |
66 |
NS** |
| Delayed phase |
75 |
69 |
NS** |
†N: Number of patients (older than 18
years of age) who received cisplatin, study drug, and had at least one
post-treatment efficacy evaluation.
‡Overall: 0 to 120 hours post-cisplatin treatment.
§Acute phase: 0 to 24 hours post-cisplatin treatment.
||Delayed phase: 25 to 120 hours post-cisplatin treatment.
*Not statistically significant when adjusted for multiple comparisons.
**Not statistically significant.
Visual analogue scale (VAS) score range: 0 mm = no nausea; 100 mm = nausea
as bad as it could be. |
Table 2 : Percent of Patients Receiving Highly Emetogenic
Chemotherapy Responding by Treatment Group and Phase for Study 2 — Cycle 1
| ENDPOINTS |
Aprepitant
Regimen
(N = 261)†
% |
Standard
Therapy
(N = 263) †
% |
p-Value |
| PRIMARY ENDPOINT |
| Complete Response |
| Overall‡ |
63 |
43 |
< 0.001 |
| OTHER PRESPECIFIED ENDPOINTS |
| Complete Response |
| Acute phase§ |
83 |
68 |
< 0.001 |
| Delayed phase|| |
68 |
47 |
< 0.001 |
| Complete Protection |
| Overall |
56 |
41 |
< 0.001 |
| Acute phase |
80 |
65 |
< 0.001 |
| Delayed phase |
61 |
44 |
< 0.001 |
| No Emesis |
| Overall |
66 |
44 |
< 0.001 |
| Acute phase |
84 |
69 |
< 0.001 |
| Delayed phase |
72 |
48 |
< 0.001 |
| No Nausea |
| Overall |
49 |
39 |
NS* |
| Delayed phase |
53 |
40 |
NS* |
| No Significant Nausea |
| Overall |
71 |
64 |
NS** |
| Delayed phase |
73 |
65 |
NS** |
†N: Number of patients (older than 18
years of age) who received cisplatin, study drug, and had at least one
post-treatment efficacy evaluation.
‡Overall: 0 to 120 hours post-cisplatin treatment.
§Acute phase: 0 to 24 hours post-cisplatin treatment.
||Delayed phase: 25 to 120 hours post-cisplatin treatment.
*Not statistically significant when adjusted for multiple comparisons.
**Not statistically significant.
Visual analogue scale (VAS) score range: 0 mm = no nausea; 100 mm = nausea
as bad as it could be. |
In both studies, a statistically significantly higher proportion of patients
receiving the aprepitant regimen in Cycle 1 had a complete response (primary
endpoint), compared with patients receiving standard therapy. A statistically
significant difference in complete response in favor of the aprepitant regimen
was also observed when the acute phase and the delayed phase were analyzed separately.
In both studies, the estimated time to first emesis after
initiation of cisplatin treatment was longer with the aprepitant regimen, and
the incidence of first emesis was reduced in the aprepitant regimen group
compared with standard therapy group as depicted in the Kaplan-Meier curves in
Figure 1.
Figure 1: Percent of Patients Receiving Highly Emetogenic
Chemotherapy Who Remain Emesis Free Over Time – Cycle 1
Patient-Reported Outcomes: The impact of
nausea and vomiting on patients' daily lives was assessed in Cycle 1 of both Phase
III studies using the Functional Living Index–Emesis (FLIE), a validated
nausea-and vomiting-specific patient-reported outcome measure. Minimal or no
impact of nausea and vomiting on patients' daily lives is defined as a FLIE
total score > 108. In each of the 2 studies, a higher proportion of patients
receiving the aprepitant regimen reported minimal or no impact of nausea and
vomiting on daily life (Study 1: 74% versus 64%; Study 2: 75% versus 64%).
Multiple-Cycle Extension: In the same 2
clinical studies, patients continued into the Multiple-Cycle extension for up
to 5 additional cycles of chemotherapy. The proportion of patients with no
emesis and no significant nausea by treatment group at each cycle is depicted
in Figure 2. Antiemetic effectiveness for the patients receiving the aprepitant
regimen is maintained throughout repeat cycles for those patients continuing in
each of the multiple cycles.
Figure 2: Proportion of Patients Receiving Highly Emetogenic
Chemotherapy With No Emesis and No Significant Nausea by Treatment Group and
Cycle
Moderately Emetogenic Chemotherapy
In a multicenter, randomized, double-blind, parallel-group,
clinical study in breast cancer patients, the aprepitant regimen (see table
that follows) was compared with a standard of care therapy in patients
receiving a moderately emetogenic chemotherapy regimen that included
cyclophosphamide 7501500 mg/m²; or cyclophosphamide 500-1500 mg/m² and
doxorubicin ( ≤ 60 mg/m²) or epirubicin ( ≤ 100 mg/m²).
In this study, the most common combinations were
cyclophosphamide + doxorubicin (60.6%); and cyclophosphamide + epirubicin +
fluorouracil (21.6%).
Of the 438 patients who were randomized to receive the
aprepitant regimen, 99.5% were women. Of these, approximately 80% were White,
8% Black, 8% Asian, 4% Hispanic, and < 1% Other. The aprepitant-treated
patients in this clinical study ranged from 25 to 78 years of age, with a mean
age of 53 years; 70 patients were 65 years or older, with 12 patients being
over 74 years.
Patients (N = 866) were randomized to either the aprepitant
regimen (N = 438) or standard therapy (N = 428). The treatment regimens are
defined in the table that follows.
Treatment Regimens Moderately Emetogenic Chemotherapy Trial
| Treatment Regimen |
Day 1 |
Days 2 to 3 |
| Aprepitant |
Aprepitant 125 mg PO†
Dexamethasone 12 mg PO‡
Ondansetron 8 mg PO x 2 doses§ |
Aprepitant 80 mg PO Daily |
| Standard Therapy |
Dexamethasone 20 mg PO
Ondansetron 8 mg PO x 2 doses |
Ondansetron 8 mg PO Daily (every 12 hours) |
Aprepitant placebo and dexamethasone placebo were used to
maintain blinding.
†1 hour prior to chemotherapy.
‡30 minutes prior to chemotherapy.
§30 to 60 minutes prior to chemotherapy and 8 hours after
first ondansetron dose. |
The antiemetic activity of EMEND was evaluated based on the following endpoints
Primary endpoint
Complete response (defined as no emetic episodes and no use
of rescue therapy) in the overall phase (0 to 120 hours post-chemotherapy)
Other prespecified endpoints
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
- no nausea (maximum VAS < 5 mm on a 0 to 100 mm scale)
- no significant nausea (maximum VAS < 25 mm on a 0 to 100 mm scale)
- complete protection (defined as no emetic episodes, no use of rescue therapy,
and a maximum nausea visual analogue scale [VAS] score < 25 mm on a 0 to
100 mm scale)
- complete response during the acute and delayed phases.
A summary of the key results from this study is shown in
Table 3.
Table 3 : Percent of Patients Receiving Moderately Emetogenic
Chemotherapy Responding by Treatment Group and Phase — Cycle 1
| ENDPOINTS |
Aprepitant
Regimen
(N = 433)†
% |
Standard
Therapy
(N = 424)†
% |
p-Value |
| PRIMARY ENDPOINT |
| Complete Response‡ |
51 |
42 |
0.015 |
| OTHER PRESPECIFIED ENDPOINTS |
| No Emesis |
76 |
59 |
NS* |
| No Nausea |
33 |
33 |
NS |
| No Significant Nausea |
61 |
56 |
NS |
| No Rescue Therapy |
59 |
56 |
NS |
| Complete Protection |
43 |
37 |
NS |
†N: Number of patients included in the
primary analysis of complete response.
‡Overall: 0 to 120 hours post-chemotherapy treatment.
*NS when adjusted for prespecified multiple comparisons rule; unadjusted
p-value < 0.001. |
In this study, a statistically significantly (p=0.015) higher proportion of
patients receiving the aprepitant regimen (51%) in Cycle 1 had a complete response
(primary endpoint) during the overall phase compared with patients receiving
standard therapy (42%). The difference between treatment groups was primarily
driven by the “No Emesis Endpoint”, a principal component of this
composite primary endpoint. In addition, a higher proportion of patients receiving
the aprepitant regimen in Cycle 1 had a complete response during the acute (0-24
hours) and delayed (25-120 hours) phases compared with patients receiving standard
therapy; however, the treatment group differences failed to reach statistical
significance, after multiplicity adjustments.
Patient-Reported Outcomes: In a phase III
study in patients receiving moderately emetogenic chemotherapy, the impact of
nausea and vomiting on patients' daily lives was assessed in Cycle 1 using the
FLIE. A higher proportion of patients receiving the aprepitant regimen reported
minimal or no impact on daily life (64% versus 56%). This difference between
treatment groups was primarily driven by the “No Vomiting Domain” of this
composite endpoint.
Multiple-Cycle Extension: Patients receiving
moderately emetogenic chemotherapy were permitted to continue into the
Multiple-Cycle extension of the study for up to 3 additional cycles of
chemotherapy. Antiemetic effect for patients receiving the aprepitant regimen
is maintained during all cycles.
Prevention of Postoperative Nausea and Vomiting (PONV)
In two multicenter, randomized, double-blind, active
comparator-controlled, parallel-group clinical studies (PONV Studies 1 and 2),
aprepitant was compared with ondansetron for the prevention of postoperative
nausea and vomiting in 1658 patients undergoing open abdominal surgery.
Patients were randomized to receive 40 mg aprepitant, 125 mg aprepitant, or 4
mg ondansetron. Aprepitant was given orally with 50 mL of water 1 to 3 hours
before anesthesia. Ondansetron was given intravenously immediately before
induction of anesthesia. A comparison between the 125 mg dose and the 40 mg
dose did not demonstrate any additional clinical benefit. The remainder of this
section will focus on the results in the 40 mg aprepitant dose recommended for
PONV.
Of the 564 patients who received 40 mg aprepitant, 92% were
women and 8% were men; of these, 58% were White, 13% Hispanic American, 7%
Multi-Racial, 14% Black, 6% Asian, and 2% Other. The age of patients treated
with 40 mg aprepitant ranged from 19 to 84 years, with a mean age of 46.1
years. 46 patients were 65 years or older, with 13 patients being 75 years or
older.
The antiemetic activity of EMEND was evaluated during the 0
to 48 hour period following the end of surgery. The two pivotal studies were of
similar design; however, they differed in terms of study hypothesis, efficacy
analyses and geographic location. PONV Study 1 was a multinational study
including the U.S., whereas, PONV Study 2 was conducted entirely in the U.S.
Efficacy measures in PONV Study 1 included:
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
in the 0 to 24 hours following the end of surgery (primary)
- complete response (defined as no emetic episodes and no use of rescue therapy)
in the 0 to 24 hours following the end of surgery (primary)
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
in the 0 to 48 hours following the end of surgery (secondary)
- time to first use of rescue medication in the 0 to 24 hours following the
end of surgery (exploratory)
- time to first emesis in the 0 to 48 hours following the end of surgery (exploratory).
A closed testing procedure was applied to control the type I
error for the primary endpoints.
The results of the primary and secondary endpoints for 40 mg
aprepitant and 4 mg ondansetron are described in Table 4:
Table 4 : PONV Study 1 Response Rates for Select Efficacy
Endpoints (Modified-Intention-to-Treat Population)
| Treatment |
n/m (%) |
Aprepitant Vs Ondansetron |
| Δ |
Odds ratio† |
Analysis |
| Primary Endpoints |
| No Vomiting 0 to 24hours (Superiority) (no emetic episodes) |
| Aprepitant 40 mg |
246/293 (84.0) |
12.6% |
2.1 |
P < 0.001* |
| Ondansetron |
200/280 (71.4) |
|
|
|
| Complete Response (Non-inferiority: If LB‡ > 0.65)
(no emesis and no rescue therapy, 0 to 24hours) |
| Aprepitant 40 mg |
187/293 (63.8) |
8.8% |
1.4 |
LB=1.02 |
| Ondansetron |
154/280 (55.0) |
|
|
|
| Complete Response (Superiority: If LB > 1.0) (no emesis
and no rescue therapy, 0 to 24hours) |
| Aprepitant 40 mg |
187/293 (63.8) |
8.8% |
1.4 |
LB=1.02+ |
| Ondansetron |
154/280 (55.0) |
|
|
|
| Secondary Endpoint |
| No Vomiting 0 to 48 (Superiority) (no emetic episodes) |
| Aprepitant 40 mg |
238/292 (81.5) |
15.2% |
2.3 |
P < 0.001* |
| Ondansetron |
185/279 (66.3) |
|
|
|
n/m = Number of responders/number of patients in analysis.
Δ Difference (%): Aprepitant 40 mg minus Ondansetron.
‡ LB= lower bound of 1-sided 97.5% confidence interval
for the odds ratio.
* P-value of two-sided test < 0.05. + Based on the prespecified fixed
sequence multiplicity strategy, Aprepitant 40 mg was not superior to Ondansetron.
† Estimated odds ratio for Aprepitant versus Ondansetron.
A value of > 1 favors Aprepitant over Ondansetron. |
The use of aprepitant did not affect the time to first use of rescue medication
when compared to ondansetron. However, compared to the ondansetron group, use
of aprepitant delayed the time to first vomiting, as depicted in Figure 3.
Figure 3 : Percent of Patients Who Remain Emesis Free During
the 48 Hours Following End of Surgery
Efficacy measures in PONV Study 2 included:
- complete response (defined as no emetic episodes and no use of rescue therapy)
in the 0 to 24 hours following the end of surgery (primary)
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
in the 0 to 24 hours following the end of surgery (secondary)
- no use of rescue therapy in the 0 to 24 hours following the end of surgery
(secondary)
- no emesis (defined as no emetic episodes regardless of use of rescue therapy)
in the 0 to 48 hours following the end of surgery (secondary)
PONV Study 2 failed to satisfy its primary hypothesis that
aprepitant is superior to ondansetron in the prevention of PONV as measured by
the proportion of patients with complete response in the 24 hours following end
of surgery.
The study demonstrated that both dose levels of aprepitant
had a clinically meaningful effect with respect to the secondary endpoint “no
vomiting” during the first 24 hours after surgery and showed that the use of 40
mg aprepitant was associated with a 16% improvement over ondansetron for the no
vomiting endpoint.
Table 5 : PONV Study 2 (Modified-Intention-to-Treat Population)
| Treatment |
n/m (%) |
Aprepitant Vs Ondansetron |
| Δ |
Odd sratio† |
p-Value |
| Primary Endpoint |
| Complete Response (no emesis and no rescue therapy,
0 to 24hours) |
| Aprepitant 40 mg |
111/248 (44.8) |
2.5% |
1.1 |
0.61 |
| Ondansetron |
104/246 (42.3) |
|
|
|
| Secondary Endpoints |
| No Vomiting (no emetic episodes, 0 to 24 hours) |
| Aprepitant 40 mg |
223/248 (89.9) |
16.3% |
3.2 |
< 0.001* |
| Ondansetron |
181/246 (73.6) |
|
|
|
| No Use of Rescue Medication (for established emesis
or nausea, 0 to 24 hours) |
| Aprepitant 40 mg |
112/248 (45.2) |
-0.7% |
1.0 |
0.83 |
| Ondansetron |
113/246 (45.9) |
|
|
|
| No Vomiting 0 to 48 (Superiority) (no emetic episodes,
0 to 48 hours) |
| Aprepitant 40 mg |
209/247 (84.6) |
17.7% |
2.7 |
< 0.001* |
| Ondansetron |
164/245 (66.9) |
|
|
|
n/m = Number of responders/number of patients in analysis.
Difference (%) : Aprepitant 40 mg minus Ondansetron.
Estimated odds ratio: Aprepitant 40mg versus Ondansetron.
* Not statistically significant after pre-specified multiplicity adjustment. |
Last updated on RxList: 8/7/2009