CLINICAL PHARMACOLOGY
Mechanism Of Action
Carfilzomib is a tetrapeptide epoxyketone proteasome
inhibitor that irreversibly binds to the N-terminal threonine-containing active
sites of the 20S proteasome, the proteolytic core particle within the 26S
proteasome. Carfilzomib had antiproliferative and proapoptotic activities in
vitro in solid and hematologic tumor cells. In animals, carfilzomib inhibited
proteasome activity in blood and tissue and delayed tumor growth in models of
multiple myeloma, hematologic, and solid tumors.
Pharmacodynamics
Intravenous carfilzomib administration resulted in
suppression of proteasome chymotrypsin-like (CT-L) activity when measured in
blood 1 hour after the first dose. Doses of carfilzomib ≥ 15 mg/m² with
or without lenalidomide and dexamethasone induced a ≥ 80% inhibition of
the CT-L activity of the proteasome. In addition, carfilzomib, 20 mg/m² intravenously
as a single agent, resulted in a mean inhibition of the low molecular mass
polypeptide 2 (LMP2) and multicatalytic endopeptidase complex-like 1 (MECL1)
subunits of the proteasome ranging from 26% to 32% and 41% to 49%,
respectively. Proteasome inhibition was maintained for ≥ 48 hours
following the first dose of carfilzomib for each week of dosing.
Pharmacokinetics
Carfilzomib at doses between 20 mg/m² and 70 mg/m² administered
as a 30-minute infusion resulted in dose-dependent increases in maximum plasma
concentrations (Cmax) and area under the curve over time to infinity (AUCinf)
in patients with multiple myeloma. A dose-dependent increase in Cmax and AUCinf
was also observed between carfilzomib 20 mg/m² and 56 mg/m² as a 2- to
10-minute infusion in patients with relapsed or refractory multiple myeloma. A
30-minute infusion resulted in a similar AUCinf, but 2- to 3-fold lower Cmax than
that observed with a 2- to 10-minute infusion at the same dose. There was no
evidence of carfilzomib accumulation following repeated administration of
carfilzomib 70 mg/m² as a 30-minute once weekly infusion or 15 and 20 mg/m² as
a 2- to 10-minute twice weekly infusion.
Table 17 lists the estimated mean average daily area
under the curve in the first cycle (AUCC1,avg), average daily area under the
curve at steady-state (AUCss) and Cmax at the highest dose in the first cycle
(Cmax,C1) for the different dosing regimens.
Table 17: Carfilzomib Exposure Parameters for
Different Dosing Regimens
Estimated Parameters (%CV) |
20/27 mg/m² twice weekly with 2- to 10-minute infusion |
20/56 mg/m² twice weekly with 30-minute infusion |
20/70 mg/m² once weekly with 30-minute infusion |
AUCC1,avg (ng•hr/mL) |
95 (40) |
170 (35) |
114 (36) |
AUCss (ng•hr/mL) |
111 (34) |
228 (28) |
150 (35) |
Cmax,C1 (ng/mL) |
1282 (17) |
1166 (29) |
1595 (36) |
CV = Coefficient of variation |
Distribution
The mean steady-state volume of distribution
of a 20 mg/m² dose of carfilzomib was 28 L. Carfilzomib is 97% bound to human
plasma proteins over the concentration range of 0.4 to 4 micromolar in vitro.
Elimination
Carfilzomib has a half-life of ≤ 1 hour on Day 1 of
Cycle 1 following intravenous doses ≥ 15 mg/m². The half-life was similar
when administered either as a 30-minute infusion or a 2- to 10-minute infusion.
The systemic clearance ranged from 151 to 263 L/hour.
Metabolism
Carfilzomib is rapidly metabolized by peptidase cleavage
and epoxide hydrolysis were the principal pathways of metabolism. Cytochrome
P450 (CYP)-mediated mechanisms contribute a minor role in overall carfilzomib
metabolism.
Excretion
Approximately 25% of the administered dose of carfilzomib
was excreted in urine as metabolites in 24 hours. Urinary and fecal excretion
of the parent compound was negligible (0.3% of total dose).
Specific Populations
Age (35-89 years), sex, race or ethnicity (80% White, 11%
Black, 6% Asians, 3% Hispanics), and mild to severe renal impairment
(creatinine clearance 15-89 mL/min) did not have clinically meaningful effects
on the pharmacokinetics of carfilzomib.
Patients With Hepatic Impairment
Compared to patients with normal hepatic function,
patients with mild (total bilirubin 1 to 1.5 × ULN and any AST or total
bilirubin ≤ ULN and AST > ULN) and moderate (total bilirubin > 1.5
to 3 × ULN and any AST) hepatic impairment had approximately 50% higher
carfilzomib AUC. The pharmacokinetics of carfilzomib has not been evaluated in
patients with severe hepatic impairment (total bilirubin > 3 × ULN and any
AST).
Patients With Renal Impairment
Relative to patients with normal renal function, ESRD
patients on hemodialysis showed 33% higher carfilzomib AUC. Since hemodialysis
clearance of Kyprolis concentrations has not been studied, the drug should be
administered after the hemodialysis procedure.
Drug Interaction Studies
Clinical Studies
Effect Of Carfilzomib On Sensitive CYP3A Substrate
Midazolam (a sensitive CYP3A substrate) pharmacokinetics
was not affected by concomitant administration of carfilzomib.
In Vitro Studies
Effect Of Carfilzomib On Cytochrome P450 (CYP) Enzymes
Carfilzomib showed direct and time-dependent inhibition
of CYP3A but did not induce CYP1A2 and CYP3A4 in vitro.
Effect Of Transporters On Carfilzomib
Carfilzomib is a P-glycoprotein (P-gp) substrate in vitro.
Effect Of Carfilzomib On Transporters
Carfilzomib inhibits P-gp in vitro. However, given that
Kyprolis is administered intravenously and is extensively metabolized, the
pharmacokinetics of Kyprolis is unlikely to be affected by P-gp inhibitors or
inducers.
Animal Toxicology And/Or Pharmacology
Cardiovascular Toxicity
Monkeys administered a single bolus intravenous dose of
carfilzomib at 3 mg/kg (approximately 1.3 times recommended dose in humans of
27 mg/m² based on BSA) experienced hypotension, increased heart rate, and
increased serum levels of troponin-T.
Chronic Administration
Repeated bolus intravenous administration of carfilzomib
at ≥ 2 mg/kg/dose in rats and 2 mg/kg/dose in monkeys using dosing
schedules similar to those used clinically resulted in mortalities that were
due to toxicities occurring in the cardiovascular (cardiac failure, cardiac
fibrosis, pericardial fluid accumulation, cardiac hemorrhage/degeneration),
gastrointestinal (necrosis/hemorrhage), renal (glomerulonephropathy, tubular
necrosis, dysfunction), and pulmonary (hemorrhage/inflammation) systems. The
dose of 2 mg/kg/dose in rats is approximately half the recommended dose in
humans of 27 mg/m² based on BSA. The dose of 2 mg/kg/dose in monkeys is
approximately equivalent to the recommended dose in humans based on BSA.
Clinical Studies
In Combination With Lenalidomide And Dexamethasone For
The Treatment Of Patients With Relapsed Or Refractory Multiple Myeloma
ASPIRE (NCT01080391)
ASPIRE was a randomized, open-label, multicenter
superiority trial which evaluated the combination of Kyprolis with lenalidomide
and dexamethasone (KRd) versus lenalidomide and dexamethasone alone (Rd)
in patients with relapsed or refractory multiple myeloma who had received 1 to
3 lines of therapy (A line of therapy is a planned course of treatment
[including sequential induction, transplantation, consolidation, and/or
maintenance] without an interruption for lack of efficacy, such as for relapse
or progressive disease). Patients who had the following were excluded from the
trial: refractory to bortezomib in the most recent regimen, refractory to
lenalidomide and dexamethasone in the most recent regimen, not responding to
any prior regimen, creatinine clearance < 50 mL/min, ALT/AST > 3.5 × ULN
and bilirubin > 2 × ULN, New York Heart Association Class III to IV
congestive heart failure, or myocardial infarction within the last 4 months. In
the KRd arm, Kyprolis was evaluated at a starting dose of 20 mg/m²,
which was increased to 27 mg/m² on Cycle 1, Day 8 onward. Kyprolis
was administered as a 10-minute infusion on Days 1, 2, 8, 9, 15, and 16 of each
28-day cycle for Cycle 1 through 12. Kyprolis was dosed on Days 1, 2, 15, and
16 of each 28-day cycle from Cycle 13 through 18. Dexamethasone 40 mg was
administered orally or intravenously on Days 1, 8, 15 and 22 of each cycle.
Lenalidomide was given 25 mg orally on Days 1 to 21 of each 28-day cycle. The
Rd treatment arm had the same regimen for lenalidomide and dexamethasone as the
KRd treatment arm. Kyprolis was administered for a maximum of 18 cycles unless
discontinued early for disease progression or unacceptable toxicity.
Lenalidomide and dexamethasone administration could continue until progression
or unacceptable toxicity. Concurrent use of thromboprophylaxis and a proton
pump inhibitor were required for both arms, and antiviral prophylaxis was
required for the KRd arm.
The 792 patients in ASPIRE were randomized 1:1 to the KRd
or Rd arm. The demographics and baseline characteristics were well-balanced
between the two arms (see Table 18). Only 53% of the patients had testing for
genetic mutations; a high-risk genetic mutation was identified for 12% of
patients in the KRd arm and in 13% in the Rd arm.
Table 18: Demographics and Baseline Characteristics in
ASPIRE (Combination Therapy for Relapsed or Refractory Multiple Myeloma)
Characteristics |
KRd Combination Therapy |
KRd Arm
(N = 396) |
Rd Arm
(N = 396) |
Age, Median, Years (min, max) |
64 (38, 87) |
65 (31, 91) |
Age ≥ 75 Years, n (%) |
43 (11) |
53 (13) |
Males, n (%) |
215 (54) |
232 (59) |
Race, n (%) |
White |
377 (95) |
377 (95) |
Black |
12 (3) |
11 (3) |
Other or Not Reported |
7 (2) |
8 (2) |
Number of Prior Regimens, n (%) |
1 |
184 (46) |
157 (40) |
2 |
120 (30) |
139 (35) |
3a |
92 (23) |
100 (25) |
Prior Transplantation, n (%) |
217 (55) |
229 (58) |
ECOG Performance Status, n (%) |
0 |
165 (42) |
175 (44) |
1 |
191 (48) |
186 (47) |
2 |
40 (10) |
35 (9) |
ISS Stage at Study Baseline, n (%) |
I |
167 (42) |
154 (39) |
II |
148 (37) |
153 (39) |
III |
73 (18) |
82 (21) |
Unknown |
8 (2) |
7 (2) |
CrCL, mL/min, Median (min, max) |
79 (39, 212) |
79 (30, 208) |
30 to < 50, n (%) |
19 (5) |
32 (8) |
50 to < 80, n (%) |
185 (47) |
170 (43) |
Refractory to Last Therapy, n (%) |
110 (28) |
119 (30) |
Refractory at Any Time to, n (%): |
|
Bortezomib |
60 (15) |
58 (15) |
Lenalidomide |
29 (7) |
28 (7) |
Bortezomib + immunomodulatory agent |
24 (6) |
27 (7) |
ECOG = Eastern Cooperative Oncology Group; CrCL =
creatinine clearance; IgG = immunoglobulin G; ISS = International Staging
System; KRd = Kyprolis, lenalidomide, and dexamethasone; Rd = lenalidomide and
dexamethasone
a Including 2 patients with 4 prior regimens. |
Patients in the KRd arm demonstrated improved PFS
compared with those in the Rd arm (HR = 0.69, with 2-sided P-value = 0.0001) as
determined using standard International Myeloma Working Group (IMWG)/European
Blood and Marrow Transplantation (EBMT) response criteria by an Independent
Review Committee (IRC).
The median PFS was 26.3 months in the KRd arm versus 17.6
months in the Rd arm (see Table 19 and Figure 1).
A pre-planned overall survival (OS) analysis was
performed after 246 deaths in the KRd arm and 267 deaths in the Rd arm. The
median follow-up was approximately 67 months. A statistically significant
advantage in OS was observed in patients in the KRd arm compared to patients in
the Rd arm (see Table 19 and Figure 2).
Table 19: Efficacy Outcomes in ASPIRE (Combination
Therapy for Relapsed or Refractory Multiple Myeloma)a
|
Combination Therapy |
KRd Arm
(N = 396) |
Rd Arm
(N = 396) |
PFSb |
Medianc, Months (95% CI) |
26.3 (23.3, 30.5) |
17.6 (15.0, 20.6) |
HR (95% CI)d |
0.69 (0.57, 0.83) |
P-value (2-sided)e |
0.0001 |
Overall Survival |
Medianc, Months (95% CI) |
48.3 (42.4, 52.8) |
40.4 (33.6, 44.4) |
HR (95% CI)d |
0.79 (0.67, 0.95) |
P-value (2-sided)e |
0.0091 |
Overall Responseb |
N with response |
345 |
264 |
ORR (%) (95% CI)f |
87 (83, 90) |
67 (62, 71) |
P-value (2-sided)g |
< 0.0001 |
Response Category, n (%) |
sCR |
56 (14) |
17 (4) |
CR |
70 (18) |
20 (5) |
VGPR |
151 (38) |
123 (31) |
PR |
68 (17) |
104 (26) |
CI = confidence interval; CR = complete response; HR =
hazard ratio; KRd = Kyprolis, lenalidomide, and dexamethasone; ORR = overall
response rate; PFS = progression-free survival; PR = partial response; Rd =
lenalidomide and dexamethasone; sCR = stringent CR; VGPR = very good partial
response
a Eligible patients had 1-3 prior lines of therapy.
b As determined by an Independent Review Committee.
c Based on Kaplan-Meier estimates.
d Based on stratified Coxâ⬙s model.
e The P-value was derived using stratified log-rank test.
f Exact confidence interval.
g The P-value was derived using Cochran Mantel Haenszel test. |
The median duration of response (DOR) was 28.6 months
(95% CI: 24.9, 31.3) for the 345 patients achieving a response in the KRd arm
and 21.2 months (95% CI: 16.7, 25.8) for the 264 patients achieving a response
in the Rd arm. The median time to response was 1 month (range 1 to 14 months)
in the KRd arm and 1 month (range 1 to 16 months) in the Rd arm.
Figure 1: Kaplan-Meier Curve of Progression-Free
Survival in ASPIRE
CI = confidence interval; EBMT = European Blood and Marrow
Transplantation; HR = hazard ratio; IMWG = International Myeloma Working Group;
KRd = Kyprolis, lenalidomide, and dexamethasone; mo = months; PFS =
progression-free survival; Rd = lenalidomide and dexamethasone arm Note: The
response and PD outcomes were determined using standard objective IMWG/EBMT
response criteria.
Figure 2: Kaplan-Meier Curve of Overall Survival in
ASPIRE
CI = confidence interval; HR = hazard ratio; KRd =
Kyprolis, lenalidomide, and dexamethasone; mo = month; OS = overall survival;
Rd = lenalidomide and dexamethasone arm
In Combination With Dexamethasone For The Treatment Of Patients
With Relapsed Or Refractory Multiple Myeloma
ENDEAVOR (NCT01568866)
ENDEAVOR was a randomized, open-label, multicenter
superiority trial of Kyprolis plus dexamethasone (Kd) versus bortezomib plus
dexamethasone (Vd) in patients with relapsed or refractory multiple myeloma who
had received 1 to 3 lines of therapy. A total of 929 patients were enrolled and
randomized (464 in the Kd arm; 465 in the Vd arm). Randomization was stratified
by prior proteasome inhibitor therapy (yes versus no), prior lines of therapy
(1 versus 2 or 3), current International Staging System stage (1 versus 2 or
3), and planned route of bortezomib administration. Patients were excluded if
they had less than PR to all prior regimens; creatinine clearance < 15
mL/min; hepatic transaminases ≥ 3 × ULN; or left-ventricular ejection
fraction < 40% or other significant cardiac conditions. This trial evaluated
Kyprolis at a starting dose of 20 mg/m², which was increased to 56 mg/m² on
Cycle 1, Day 8 onward. Kyprolis was administered twice weekly as a 30-minute
infusion on Days 1, 2, 8, 9, 15, and 16 of each 28-day cycle. Dexamethasone 20
mg was administered orally or intravenously on Days 1, 2, 8, 9, 15, 16, 22, and
23 of each cycle. In the Vd arm, bortezomib was dosed at 1.3 mg/m² intravenously
or subcutaneously on Days 1, 4, 8, and 11 of a 21-day cycle, and dexamethasone
20 mg was administered orally or intravenously on Days 1, 2, 4, 5, 8, 9, 11,
and 12 of each cycle. Concurrent use of thromboprophylaxis was optional, and
prophylaxis with an antiviral agent and proton pump inhibitor was required. Of
the 465 patients in the Vd arm, 381 received bortezomib subcutaneously.
Treatment continued until disease progression or unacceptable toxicity.
The demographics and baseline characteristics are
summarized in Table 20.
Table 20: Demographics and Baseline Characteristics in
ENDEAVOR (Combination Therapy for Relapsed or Refractory Multiple Myeloma)
Characteristics |
Kd Arm
(N = 464) |
Vd Arm
(N = 465) |
Age, Years |
Median (min, max) |
65 (35, 89) |
65 (30, 88) |
< 65, n (%) |
223 (48) |
210 (45) |
65-74, n (%) |
164 (35) |
189 (41) |
≥ 75, n (%) |
77 (17) |
66 (14) |
Sex, n (%) |
Female |
224 (48) |
236 (51) |
Male |
240 (52) |
229 (49) |
Race, n (%) |
White |
353 (76) |
361 (78) |
Black |
7 (2) |
9 (2) |
Asian |
56 (12) |
57 (12) |
Other or Not Reported |
48 (10) |
38 (8) |
ECOG Performance Status, n (%) |
0 |
221 (48) |
232 (50) |
1 |
210 (45) |
203 (44) |
2 |
33 (7) |
30 (6) |
Creatinine Clearance (mL/min) |
Median (min, max) |
73 (14, 185) |
72 (12, 208) |
< 30, n (%) |
28 (6) |
28 (6) |
30 - < 50, n (%) |
57 (12) |
71 (15) |
50 - < 80, n (%) |
186 (40) |
177 (38) |
≥ 80, n (%) |
193 (42) |
189 (41) |
FISH, n (%) |
High-risk |
97 (21) |
113 (24) |
Standard-risk |
284 (61) |
291 (63) |
Unknown-risk |
83 (18) |
61 (13) |
ISS Stage at Study Baseline, n (%) |
ISS I |
219 (47) |
212 (46) |
ISS II |
138 (30) |
153 (33) |
ISS III |
107 (23) |
100 (22) |
Number of Prior Regimens, n (%) |
1 |
232 (50) |
231 (50) |
2 |
158 (34) |
144 (31) |
3 |
74 (16) |
88 (19) |
4 |
0 (0) |
2 (0.4) |
Prior Therapies, n (%) |
464 (100) |
465 (100) |
Bortezomib |
250 (54) |
252 (54) |
Transplant for Multiple Myeloma |
266 (57) |
272 (59) |
Thalidomide |
212 (46) |
249 (54) |
Lenalidomide |
177 (38) |
178 (38) |
Bortezomib + immunomodulatory agent |
159 (34) |
168 (36) |
Refractory to last prior therapy, n (%)a |
184 (40) |
189 (41) |
ECOG = Eastern Cooperative Oncology Group; FISH =
Fluorescence in situ hybridization; ISS = International Staging System; Kd =
Kyprolis plus dexamethasone; Vd = bortezomib and dexamethasone
a Refractory = disease not achieving a minimal response or better,
progressing during therapy, or progressing within 60 days after completion of
therapy. |
The efficacy of Kyprolis was evaluated by PFS as
determined by an IRC using IMWG response criteria. The trial showed a median
PFS of 18.7 months in the Kd arm versus 9.4 months in the Vd arm (see
Table 21 and Figure 3).
Figure 3: Kaplan-Meier Plot of Progression-Free
Survival in ENDEAVOR
CI = confidence interval; HR = hazard ratio; Kd =
Kyprolis plus dexamethasone; mo = months; PFS = progression-free survival; Vd =
bortezomib and dexamethasone
Other endpoints included OS and overall response rate
(ORR).
A pre-planned OS analysis was performed after 189 deaths
in the Kd arm and 209 deaths in the Vd arm. The median follow-up was approximately
37 months. A significantly longer OS was observed in patients in the Kd arm
compared to patients in the Vd arm (HR = 0.79; 95% CI: 0.65, 0.96; P-value =
0.01) (see Table 21 and Figure 4).
ORR was 77% for patients in the Kd arm and 63% for
patients in the Vd arm (see Table 21).
Table 21: Summary of Key Results in ENDEAVOR
(Intent-to-Treat Population)a
|
Kd Arm
(N = 464) |
Vd Arm
(N = 465) |
PFSb |
Number of events (%) |
171 (37) |
243 (52) |
Medianc, Months (95% CI) |
18.7 (15.6, NE) |
9.4 (8.4, 10.4) |
Hazard Ratio (Kd/Vd) (95% CI)d |
0.53 (0.44, 0.65) |
P-value (1-sided)e |
< 0.0001 |
Overall Survival |
Number of deaths (%) |
189 (41) |
209 (45) |
Medianc, Months (95% CI) |
47.6 (42.5, NE) |
40.0 (32.6, 42.3) |
Hazard Ratio (Kd/Vd) (95% CI)d |
0.79 (0.65, 0.96) |
P-value (1-sided)e |
0.01 |
Overall Responseb |
N with Response |
357 |
291 |
ORR (%) (95% CI)f |
77 (73, 81) |
63 (58, 67) |
P-value (1-sided)g |
< 0.0001 |
Response Category, n (%) |
sCR |
8 (2) |
9 (2) |
CR |
50 (11) |
20 (4) |
VGPR |
194 (42) |
104 (22) |
PRh |
105 (23) |
158 (34) |
CI = confidence interval; CR = complete response; Kd =
Kyprolis and dexamethasone; ORR = overall response rate; PFS = progression-free
survival; PR = partial response; sCR = stringent CR; Vd = bortezomib and
dexamethasone; VGPR = very good partial response; NE = non-estimable
a Eligible patients had 1-3 prior lines of therapy.
b PFS and ORR were determined by an Independent Review Committee.
c Based on Kaplan-Meier estimates.
d Based on a stratified Coxâ⬙s model.
e P-value was derived using a stratified log-rank test.
f Exact confidence interval.
g The P-value was derived using Cochran Mantel Haenszel test.
h Includes one patient in each arm with a confirmed PR which may not
have been the best response. |
Figure 4: Kaplan-Meier Plot of Overall Survival in
ENDEAVOR
CI = confidence interval; HR = hazard ratio; Kd =
Kyprolis plus dexamethasone; mo = month; OS = overall survival; Vd = bortezomib
and dexamethasone
The median DOR in subjects achieving PR or better was
21.3 months (95% CI: 21.3, not estimable) in the Kd arm and 10.4 months (95%
CI: 9.3, 13.8) in the Vd arm. The median time to response was 1 month (range
< 1 to 8 months) in both arms.
A.R.R.O.W. (NCT02412878)
A.R.R.O.W. was a randomized, open-label, multicenter
superiority trial of Kyprolis plus dexamethasone (Kd) once weekly (20/70 mg/m²)
versus Kd twice weekly (20/27 mg/m²) in patients with relapsed and refractory
multiple myeloma who had received 2 to 3 prior lines of therapy. Patients were
excluded if they had less than PR to at least one prior line; creatinine
clearance < 30 mL/min; hepatic transaminases ≥ 3 × ULN; or
left-ventricular ejection fraction < 40% or other significant cardiac
conditions. A total of 478 patients were enrolled and randomized (240 in 20/70
mg/m² arm; 238 in 20/27 mg/m² arm). Randomization was stratified by current
International Staging System stage (stage 1 versus stages 2 or 3), refractory
to bortezomib treatment (yes versus no), and age (< 65 versus ≥ 65
years). Arm 1 of this trial evaluated Kyprolis at a starting dose of 20 mg/m²,
which was increased to 70 mg/m² on Cycle 1, Day 8 onward. Arm 1 Kyprolis was
administered once weekly as a 30-minute infusion on Days 1, 8 and 15, of each
28-day cycle. Arm 2 of this trial evaluated Kyprolis at a starting dose of 20
mg/m², which was increased to 27 mg/m² on Cycle 1, Day 8 onward. Arm 2 Kyprolis
was administered twice weekly as a 10-minute infusion on Days 1, 2, 8, 9, 15,
and 16 of each 28-day cycle. In both regimens, dexamethasone 40 mg was
administered orally or intravenously on Days 1, 8, 15 for all cycles and on Day
22 for cycles 1 to 9 only. Concurrent use of thromboprophylaxis was optional,
prophylaxis with an antiviral agent was recommended, and prophylaxis with a
proton pump inhibitor was required. Treatment continued until disease
progression or unacceptable toxicity.
The demographics and baseline characteristics are
summarized in Table 22.
Table 22: Demographics and Baseline Characteristics in
A.R.R.O.W. (Combination Therapy for Relapsed and Refractory Multiple Myeloma)
Characteristics |
Once weekly Kd 20/70 mg/m² Arm
(N = 240) |
Twice weekly Kd 20/27 mg/m² Arm
(N = 238) |
Age, Years |
Median (min, max) |
66 (39, 85) |
66 (35, 83) |
< 65, n (%) |
104 (43) |
104 (44) |
65 - 74, n (%) |
90 (38) |
102 (43) |
≥ 75, n (%) |
46 (19) |
32 (13) |
Sex, n (%) |
Female |
108 (45) |
110 (46) |
Male |
132 (55) |
128 (54) |
Race, n (%) |
White |
200 (83) |
202 (85) |
Black |
3 (1) |
2 (1) |
Asian |
30 (13) |
15 (6) |
Other or Not Reported |
7 (3) |
19 (8) |
ECOG Performance Status, n (%) |
0 |
118 (49) |
118 (50) |
1 |
121 (50) |
120 (50) |
2 |
1 (0.4) |
0 (0) |
Creatinine Clearance (mL/min) |
Median (min, max) |
70.80 (28, 212) |
73.20 (29, 181) |
< 30, n (%) |
2 (1) |
1 (0.4) |
30 - < 50, n (%) |
48 (20) |
34 (14) |
50 - < 80, n (%) |
91 (38) |
111 (47) |
≥ 80, n (%) |
99 (41) |
91 (38) |
FISH, n (%) |
High-risk |
34 (14) |
47 (20) |
Standard-risk |
47 (20) |
53 (22) |
Unknown-risk |
159 (66) |
138 (58) |
ISS Stage at Study Baseline, n (%) |
ISS I |
94 (39) |
99 (42) |
ISS II |
80 (33) |
81 (34) |
ISS III |
63 (26) |
54 (23) |
Number of Prior Regimens, n (%) |
2 |
116 (48) |
125 (53) |
3 |
124 (52) |
112 (47) |
>3 |
0 (0) |
1 (0.4) |
Prior Therapies, n (%) |
Bortezomib |
236 (98) |
237 (100) |
Transplantation |
146 (61) |
157 (66) |
Thalidomide |
119 (50) |
119 (50) |
Lenalidomide |
207 (86) |
194 (82) |
ECOG = Eastern Cooperative Oncology Group; FISH =
Fluorescence in situ hybridization; ISS = International Staging System; Kd =
Kyprolis plus dexamethasone |
The efficacy of Kyprolis was evaluated by PFS using IMWG
response criteria. The trial showed a median PFS of 11.2 months in the once
weekly Kd 20/70 mg/m² arm versus 7.6 months in the twice weekly Kd 20/27 mg/m² arm
(see Table 23 and Figure 5).
Figure 5: Kaplan-Meier Plot of Progression-Free
Survival in A.R.R.O.W.
CI = confidence interval; HR = hazard ratio; Kd =
Kyprolis plus dexamethasone; PFS = progression-free survival
Other endpoints included ORR. ORR was 62.9% for patients
in the Kd 20/70 mg/m² once weekly arm and 40.8% for patients in the Kd 20/27
mg/m² twice weekly arm (see Table 23).
Table 23: Summary of Key Results in A.R.R.O.W.
(Intent-to-Treat Population)
|
Once weekly Kd 20/70 mg/m² Arm
(N = 240) |
Twice weekly Kd 20/27 mg/m² Arm
(N = 238) |
PFS |
Number of events, n (%) |
126 (52.5) |
148 (62.2) |
Median, Months (95% CI) |
11.2 (8.6, 13.0) |
7.6 (5.8, 9.2) |
Hazard Ratio (Once weekly Kd 20/70 mg/m²/Twice weekly Kd 20/27 mg/m²) (95% CI) |
0.69 (0.54, 0.88) |
P-value (1-sided) |
0.0014 |
Overall Responsea |
N with Response |
151 |
97 |
ORR (%) (95% CI) |
62.9 (56.5, 69.0) |
40.8 (34.5, 47.3) |
P-value (1-sided) |
< 0.0001 |
Response Category, n (%) |
sCR |
4 (1.7) |
0 (0.0) |
CR |
13 (5.4) |
4 (1.7) |
VGPR |
65 (27.1) |
28 (11.8) |
PR |
69 (28.8) |
65 (27.3) |
CI = confidence interval; Kd = Kyprolis/dexamethasone;
ORR = overall response rate; PFS = progression free survival; sCR = stringent
complete response; CR = complete response; VGPR = very good partial response;
PR = partial response
a Overall response is defined as achieving a best overall response
of PR, VGPR, CR or sCR. |
The median DOR in subjects achieving PR or better was 15
months (95% CI: 12.2, not estimable) in the Kd 20/70 mg/m² arm and 13.8 months
(95% CI: 9.5, not estimable) in the Kd 20/27 mg/m² arm. The median time to
response was 1.1 months in the Kd 20/70 mg/m² arm and 1.9 months in the Kd
20/27 mg/m² arm.
Kyprolis is not approved for twice weekly 20/27 mg/m² administration
in combination with dexamethasone alone.
Monotherapy For The Treatment Of Patients With Relapsed Or
Refractory Multiple Myeloma
Study PX-171-007 (NCT00531284)
Study PX-171-007 was a multicenter, open-label, dose
escalation, single-arm trial that evaluated the safety of carfilzomib
monotherapy as a 30-minute infusion in patients with relapsed or refractory
multiple myeloma after 2 or more lines of therapy. Patients were excluded if
they had a creatinine clearance < 20 mL/min; ALT ≥ 3 × upper limit of
normal (ULN), bilirubin ≥ 1.5 × ULN; New York Heart Association Class III
or IV congestive heart failure; or other significant cardiac conditions. A total
of 24 subjects with multiple myeloma were enrolled at the maximum tolerated
dose level of 20/56 mg/m². Carfilzomib was administered twice weekly for 3
consecutive weeks (Days 1, 2, 8, 9, 15, and 16) of a 28-day cycle. In Cycle 13
onward, the Day 8 and 9 carfilzomib doses could be omitted. Patients received
carfilzomib at a starting dose of 20 mg/m² on Days 1 and 2 of Cycle 1, which
was increased to 56 mg/m² for all subsequent doses. Dexamethasone 8 mg orally
or intravenously was required prior to each carfilzomib dose in Cycle 1 and was
optional in subsequent cycles. Treatment was continued until disease
progression or unacceptable toxicity.
Efficacy was evaluated by ORR and DOR. ORR by
investigator assessment was 50% (95% CI: 29, 71) per IMWG criteria (see Table
24). The median DOR in subjects who achieved a PR or better was 8.0 months
(Range: 1.4, 32.5).
Table 24: Response Categories in Study PX-171-007
(20/56 mg/m² Monotherapy Regimen)
Characteristics |
Study Patientsa
n (%) |
Number of Patients (%) |
24 (100) |
Overall Responseb |
12 (50) |
95% CIc |
(29, 71) |
Response Category |
sCR |
1 (4) |
CR |
0 (0) |
VGPR |
4 (17) |
PR |
7 (29) |
CI = confidence interval; CR = complete response; PR =
partial response; sCR = stringent complete response; ÃÂ VGPR = very good partial
response
a Eligible patients had 2 or more prior lines of therapy.
b Per investigator assessment.
c Exact confidence interval. |
Study PX-171-003 A1 (NCT00511238)
Study PX-171-003 A1 was a single-arm, multicenter
clinical trial of Kyprolis monotherapy by up to 10-minute infusion. Eligible
patients were those with relapsed and refractory multiple myeloma who had
received at least two prior therapies (including bortezomib and thalidomide
and/or lenalidomide) and had ≤ 25% response to the most recent therapy or
had disease progression during or within 60 days of the most recent therapy.
Patients were excluded from the trial if they were refractory to all prior therapies
or had a total bilirubin ≥ 2 × ULN; creatinine clearance < 30 mL/min;
New York Heart Association Class III to IV congestive heart failure;
symptomatic cardiac ischemia; myocardial infarction within the last 6 months;
peripheral neuropathy Grade 3 or 4, or peripheral neuropathy Grade 2 with pain;
active infections requiring treatment; or pleural effusion.
Kyprolis was administered intravenously up to 10 minutes
on two consecutive days each week for three weeks, followed by a 12-day rest
period (28-day treatment cycle), until disease progression, unacceptable
toxicity, or for a maximum of 12 cycles. Patients received 20 mg/m² at each
dose in Cycle 1, and 27 mg/m² in subsequent cycles. Dexamethasone 4 mg orally
or intravenously was administered prior to Kyprolis doses in the first and
second cycles.
A total of 266 patients were enrolled. Baseline patient
and disease characteristics are summarized in Table 25.
Table 25: Demographics and Baseline Characteristics in
Study PX-171-003 A1 (20/27 mg/m² Monotherapy Regimen for Relapsed and
Refractory Multiple Myeloma)
Characteristics |
Number of Patients (%) |
Patient Characteristics |
Enrolled patients |
266 (100) |
Median age, years (range) |
63 (37, 87) |
Age group, < 65 / ≥ 65 (years) |
146 (55) / 120 (45) |
Gender (male / female) |
155 (58) / 111 (42) |
Race (White / Black / Asian / Other) |
190 (71) / 53 (20) / 6 (2) / 17 (6) |
Disease Characteristics |
Number of Prior Regimens (median) |
5a |
Prior Transplantation |
198 (74) |
Refractory Status to Most Recent Therapyb |
Refractory: Progression during most recent therapy |
198 (74) |
Refractory: Progression within 60 days after completion of most recent therapy |
38 (14) |
Refractory: ≤ 25% response to treatment |
16 (6) |
Relapsed: Progression after 60 days post treatment |
14 (5) |
Years since diagnosis, median (range) |
5.4 (0.5, 22.3) |
Plasma cell involvement (< 50% / ≥ 50% / unknown) |
143 (54) / 106 (40) / 17 (6) |
ISS Stage at Study Baseline |
I |
76 (29) |
II |
102 (38) |
III |
81 (31) |
Unknown |
7 (3) |
Cytogenetics or FISH analyses |
Normal/Favorable |
159 (60) |
Poor Prognosis |
75 (28) |
Unknown |
32 (12) |
Creatinine clearance < 30 mL/min |
6 (2) |
FISH = Fluorescence in situ hybridization; ISS = International
Staging System
a Range: 1, 20.
b Categories for refractory status are derived by programmatic
assessment using available laboratory data. |
Efficacy was evaluated by ORR as determined by IRC
assessment using IMWG criteria. The median number of cycles started was four.
The ORR (PR or better) was 23% (95% CI: 18, 28) (see Table 26). The median DOR
was 7.8 months (95% CI: 5.6, 9.2).
Table 26: Response Categories in Study PX-171-003 A1
(20/27 mg/m² Monotherapy Regimen)
Characteristics |
Study Patientsa
n (%) |
Number of Patients (%) |
266 (100) |
Overall Responseb |
61 (23) |
95% CIc |
(18, 28) |
Response Category |
CR |
1 (< 1) |
VGPR |
13 (5) |
PR |
47 (18) |
CI = confidence interval; CR = complete response;
PR=partial response; VGPR = very good partial response
a Eligible patients had 2 or more prior lines of therapy and were
refractory to the last regimen.
b As assessed by the Independent Review Committee.
c Exact confidence interval. |
Study PX-171-004 Part 2 (NCT00530816)
Study PX-171-004 Part 2 was a single-arm, multicenter
clinical trial of Kyprolis monotherapy by up to 10-minute infusion. Eligible
patients were those with relapsed or refractory multiple myeloma who were
bortezomib-naïve, had received one to three prior lines of therapy and had
≤ 25% response or progression during therapy or within 60 days after
completion of therapy. Patients were excluded from the trial if they were
refractory to standard first-line therapy or had a total bilirubin ≥ 2 ×
ULN; creatinine clearance < 30 mL/min; New York Heart Association Class III
to IV congestive heart failure; symptomatic cardiac ischemia; myocardial
infarction within the last 6 months; active infections requiring treatment; or
pleural effusion.
Kyprolis was administered intravenously up to 10 minutes
on two consecutive days each week for three weeks, followed by a 12-day rest
period (28-day treatment cycle), until disease progression, unacceptable
toxicity, or for a maximum of 12 cycles. Patients received 20 mg/m² at each
dose in Cycle 1, and 27 mg/m² in subsequent cycles. Dexamethasone 4 mg orally
or intravenously was administered prior to Kyprolis doses in the first and
second cycles.
A total of 70 patients were treated with this 20/27 mg/m²
regimen. Baseline patient and disease characteristics are summarized in Table
27.
Table 27: Demographics and Baseline Characteristics in
Study PX-171-004 Part 2 (20/27 mg/m² Monotherapy Regimen for Relapsed or
Refractory Multiple Myeloma)
Characteristics |
Number of Patients (%) |
Patient Characteristics |
Enrolled patients |
70 (100) |
Median age, years (range) |
66 (45, 85) |
Age group, < 65 / ≥ 65 (years) |
31 (44) / 39 (56) |
Gender (male / female) |
44 (63) / 26 (37) |
Race (White / Black / Asian / Hispanic / Other) |
52 (74) / 12 (17) / 3 (4) / 2 (3) / 1 (1) |
Disease Characteristics |
Number of Prior Regimens (median) |
2a |
Prior Transplantation |
47 (67) |
Refractory Status to Most Recent Therapyb |
Refractory: Progression during most recent therapy |
28 (40) |
Refractory: Progression within 60 days after completion of most recent therapy |
7 (10) |
Refractory: ≤ 25% response to treatment |
10 (14) |
Relapsed: Progression after 60 days post treatment |
23 (33) |
No Signs of Progression |
2 (3) |
Years since diagnosis, median (range) |
3.6 (0.7, 12.2) |
Plasma cell involvement (< 50% / ≥ 50% / unknown) |
54 (77) / 14 (20) / 1 (1) |
ISS Stage at Study Baseline, n (%) |
|
I |
28 (40) |
II |
25 (36) |
III |
16 (23) |
Unknown |
1 (1) |
Cytogenetics or FISH analyses |
|
Normal/Favorable |
57 (81) |
Poor Prognosis |
10 (14) |
Unknown |
3 (4) |
Creatinine clearance < 30 mL/min |
1 (1) |
FISH = Fluorescence in situ hybridization; ISS =
International Staging System
a Range: 1, 4.
b Categories for refractory status are derived by programmatic
assessment using available laboratory data. |
Efficacy was evaluated by ORR as determined by IRC
assessment using IMWG criteria. The median number of cycles started was seven.
The ORR (PR or better) was 50% (95% CI: 38, 62) (see Table 28). The median DOR
was not reached.
Table 28: Response Categories in Study PX-171-004 Part
2 (20/27 mg/m² Monotherapy Regimen)
Characteristics |
Study Patientsa
n (%) |
Number of Patients (%) |
70 (100) |
Overall Responseb |
35 (50) |
95% CIc |
(38 - 62) |
Response Category |
CR |
1 (1) |
VGPR |
18 (26) |
PR |
16 (23) |
CI = confidence interval; CR = complete response; PR =
partial response; VGPR = very good partial response
a Eligible patients had 1-3 prior lines of therapy and were
refractory to the last regimen.
b As assessed by an Independent Review Committee.
c Exact confidence interval. |