This phase I study in Japanese patients evaluated the safety, pharmacokinetics, and preliminary efficacy of palbociclib, a highly selective and reversible oral cyclin‐dependent kinase 4/6 inhibitor, ...as monotherapy for solid tumors (part 1) and combined with letrozole as first‐line treatment of postmenopausal patients with estrogen receptor‐positive, human epidermal growth factor receptor 2‐negative advanced breast cancer (part 2). Part 1 evaluated palbociclib 100 and 125 mg once daily (3 weeks on/1 week off; n = 6 each group) to determine the maximum tolerated dose. Part 2 evaluated palbociclib maximum tolerated dose (125 mg) plus letrozole 2.5 mg (n = 6). The most common treatment‐related adverse event was neutropenia (all grades/grade 3/4): 100 mg, 83%/67%; 125 mg, 67%/33%; and palbociclib plus letrozole, 100%/83%. Heavier pretreatment with chemotherapy may have resulted in higher neutropenia rates observed with the 100‐mg dose. Palbociclib exposure was higher with 125 vs 100 mg (mean area under the plasma concentration–time curve over dosing interval τ: 1322 vs 547.5 ng·h/mL single dose, 2838 vs 1276 ng·h/mL multiple dose; mean maximum plasma concentration: 104.1 vs 41.4 ng/mL single dose, 185.5 vs 77.4 ng/mL multiple dose). Half‐life was 23–26 h. No drug–drug interactions between palbociclib and letrozole occurred. Four patients had stable disease (≥24 weeks in one patient with rectal cancer 100 mg and one with esophageal cancer 125 mg) in part 1; two patients had partial response and two had stable disease (both ≥24 weeks) in part 2. Palbociclib at the 125‐mg dose (schedule 3/1) was tolerated and is the recommended dose for monotherapy and letrozole combination therapy in Japanese patients. The trials are registered with www.ClinicalTrials.gov: A5481010 and NCT01684215.
This phase 1 study in Japanese patients evaluates the safety, pharmacokinetics, and preliminary efficacy of palbociclib as monotherapy for solid tumors (part 1) and combined with letrozole as first‐line treatment of postmenopausal patients with ER+/HER2− advanced breast cancer (part 2). Overall, the results of this study suggest that palbociclib 125 mg was tolerated and is a recommended dose for monotherapy and letrozole combination therapy in Japanese patients.
Background
In the double-blind, phase 3 PALOMA-3 study, palbociclib–fulvestrant significantly prolonged progression-free survival versus placebo–fulvestrant in patients with hormone receptor-positive ...(HR+), human epidermal growth factor receptor 2-negative (HER2–) metastatic breast cancer (MBC) whose disease had progressed on prior endocrine therapy. The present study evaluated the efficacy, safety, and pharmacokinetics of palbociclib plus fulvestrant in Japanese patients enrolled in PALOMA-3.
Methods
Pre/peri/postmenopausal women with HR+/HER2– MBC were randomized 2:1 to fulvestrant (500 mg) and either palbociclib (125 mg/day; 3 weeks on/1 week off;
n
= 347) or placebo (
n
= 174). Prespecified exploratory analyses compared the efficacy (data cutoff: October 23, 2015), safety, and pharmacokinetics (data cutoff: December 5, 2014) in Japanese women versus the overall population.
Results
A total of 35 Japanese women were randomized to palbociclib–fulvestrant (
n
= 27) or placebo–fulvestrant (
n
= 8). Median progression-free survival was 13.6 months (95% CI, 7.5–not estimable) in the Japanese palbociclib–fulvestrant group and 11.2 months (95% CI, 5.6–not estimable) in the placebo–fulvestrant group. The most common adverse event (AE) in Japanese patients was neutropenia (all grades, 93%); no discontinuations were due to an AE. Geometric mean trough concentration values (within-subject mean steady state) for palbociclib were similar for Japanese Asian (excluding Japanese), and non-Asian patients (84.4 ng/mL, 86.3 ng/mL, and 74.8 ng/mL, respectively).
Conclusion(s)
The results for the overall population and Japanese patients in PALOMA-3 suggest that palbociclib plus fulvestrant was effective and well tolerated in Japanese patients with HR+/HER2‒ MBC whose disease had progressed on prior endocrine therapy (Pfizer; NCT01942135).
This single‐arm, open‐label, phase II study in 42 Japanese postmenopausal patients with estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative (ER+/HER2−) advanced breast cancer ...evaluated the efficacy, safety, and pharmacokinetics of first‐line palbociclib (125 mg once daily, 3 weeks on/1 week off) coadministered with letrozole (2.5 mg once daily). Primary endpoint of investigator‐assessed 1‐year progression‐free survival (PFS) probability was 75.0% (90% CI, 61.3%‐84.4%), far surpassing the 40% lower limit of the 90% CI supporting efficacy. Median duration of treatment was 438 days. Among secondary efficacy measures, median PFS was not reached (95% CI, 16.7: not estimable), 17/42 patients (40.5%) had an objective response, 36/42 (85.7%) maintained disease control, and 27/42 (64.3%) remained in follow‐up. Median overall survival was not reached, and 1‐year survival probability was 92.9% (95% CI, 79.5%‐97.6%). Results of intensive pharmacokinetics in a subset of 6 patients showed palbociclib steady‐state mean area under the plasma concentration‐time curve over the dosing interval τ and mean maximum plasma concentration were 1979 ng·h/mL and 124.7 ng/mL, respectively. For day 15 plasma samples from cycles 1 and 2, geometric mean of the within‐patient mean trough concentration was 90.1 ng/mL. The most common treatment‐related adverse events were neutropenia (100%) and stomatitis (73.8%). There was 1 case of treatment‐related febrile neutropenia. Toxicities were generally tolerated and manageable by dose modifications and/or medical care. Efficacy and safety of first‐line palbociclib plus letrozole therapy is supported in Japanese postmenopausal patients with treatment‐naive ER+/HER2− advanced breast cancer.
The results of this phase II study support the efficacy and safety of palbociclib in combination with letrozole as first‐line therapy in Japanese postmenopausal patients with estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative advanced breast cancer. The primary endpoint of investigator‐assessed 1‐year progression‐free survival probability was 75.0% (90% CI, 61.3%‐84.4%). The most common treatment‐related adverse events (neutropenia and stomatitis) were tolerable and could be managed with dose reductions, dose interruptions, and/or standard medical care.
Background
In PALOMA-2, palbociclib–letrozole significantly improved progression-free survival (PFS) vs placebo–letrozole in women with estrogen receptor–positive, human epidermal growth factor ...receptor 2–negative (ER+/HER2–) advanced breast cancer (ABC) in the first-line setting. We evaluated the efficacy, safety, and pharmacokinetics of palbociclib in Japanese women in PALOMA-2.
Methods
In this phase 3 study, 666 postmenopausal women with ER+/HER2– ABC were randomized 2:1 to palbociclib (125 mg/day 3 weeks on/1 week off) plus letrozole (2.5 mg daily) or placebo plus letrozole. A prespecified, exploratory, subgroup analysis of Japanese patients (
n
= 46) was conducted to compare results with those of the overall population.
Results
At the February 26, 2016 cutoff, median PFS among the 46 Japanese patients was 22.2 months (95%CI, 13.6‒not estimable) with palbociclib–letrozole vs 13.8 months (5.6‒22.2) with placebo–letrozole (hazard ratio, 0.59 95%CI, 0.26−1.34). The most common adverse events (AEs) were hematologic and more frequent among Japanese patients than the overall population (neutropenia: 93.8% 87.5% grade 3/4 vs 79.5% 66.4%; leukopenia: 62.5% 43.8% vs 39.0% 24.8%); no Japanese patients had febrile neutropenia. Palbociclib dose reductions due to toxicity (mainly neutropenia) were more common in Japanese patients (62.5% vs 36.0%); few permanently discontinued due to AEs. Although mean palbociclib trough concentration was higher in Japanese patients vs non-Asians (95.4 vs 61.7 ng/mL), the range of individual values of the Japanese patients was within that of non-Asians.
Conclusions
These results from PALOMA-2 suggest that palbociclib–letrozole merits consideration as a first-line treatment option for postmenopausal Japanese patients with ER+/HER2‒ ABC. ClinicalTrials.gov: NCT01740427.
Post-marketing surveillance (PMS) was performed in Japan to obtain information on the safety and efficacy of crizotinib.
Target patients included almost all patients with anaplastic lymphoma ...kinase-positive non-small cell lung cancer who were administered crizotinib. The observation period was 52 weeks. In the present study, we focused on the treatment status and safety of crizotinib therapy and analyzed the real-world data obtained by this PMS (ClinicalTrials.gov: NCT01597258).
The safety analysis set included 2028 Japanese patients, and more than half of the patients (56.4%) were nonsmokers. The incidence of adverse drug reactions (ADRs) was 91.6%, and common ADRs (incidence ≥15%) were nausea (32.2%), diarrhea (24.3%), photopsia (18.9%), vomiting (17.5%) and dysgeusia (16.8%). Many patients (623 patients) discontinued treatment of crizotinib because of adverse events within 12 weeks after therapy initiation, which tended to frequently occur in the following cases: (1) elderly, (2) body weight <40 kg, (3) body surface area <1.2 m2 (4) ECOG PS 2-4, (5) higher Brinkman index and (6) history of occupational/environmental exposure such as asbestos/pneumoconiosis. The proportions of patients remaining on crizotinib therapy were 68.2% for 3 months, 55.2% for 6 months and 36.1% for 12 months, with a median duration of 7.9 months. Multivariate analysis with a Cox proportional hazard model identified 10 statistically significant patient background factors influencing the duration of crizotinib therapy.
No new safety concerns were observed in this PMS study. Our results provide useful information regarding the status of crizotinib therapy in the clinical setting.
Pegvisomant is a GH receptor antagonist and strong inhibitor of insulin-like growth factor I (IGF-I) production. The treatment goal for acromegaly is to normalize serum IGF-I levels and attenuate ...associated symptoms. The efficacy and safety of pegvisomant as treatment for acromegaly have been reported in Caucasians, but not in Japanese. Here we report the clinical experience of using pegvisomant in Japanese patients with acromegaly. The efficacy and safety data for pegvisomant from two open-labeled clinical studies in Japan, conducted from 2004 to 2007, were re-analyzed using the new Japanese age- and sex-matched normative ranges for IGF-I. Eighteen patients with active acromegaly were enrolled in an initial pivotal study, and 16 of them were moved to a long-term (max 168 weeks) extension study. The dose of pegvisomant in the extension study was adjusted to 10-30 mg per day according to IGF-I levels. IGF-I normalization was observed in 81.3% (13/16 patients) during the extension study. The mean percentage decrease from baseline in serum IGF-I level was 64.7% at the time of last observation. The clinical symptoms and overall health status were improved, and the ring size was reduced over time until Week 12 and maintained. For safety, no clinically significant changes were observed both in the pituitary tumor size and the anti-GH antibody level. Three subjects were withdrawn from the studies due to an abnormal elevation of liver enzymes which resolved after discontinuation. Pegvisomant demonstrated excellent clinical efficacy and was well tolerated in Japanese patients with acromegaly.
In an interim analysis of a Phase II trial in Japanese patients with pancreatic neuroendocrine tumors (panNETs), sunitinib demonstrated antitumor activity with an objective response rate (ORR) of 50% ...(95% confidence interval CI, 21-79) and a median progression-free survival (PFS) of 16.8 months (95% CI, 9.3-26.2). Here, we report the final analyses of efficacy and safety, as well as additional analyses, from this Phase II study.
This was a multicenter, open-label, Phase II trial (NCT01121562) of sunitinib in Japanese patients with panNETs. Patients received oral sunitinib 37.5 mg/day on a continuous daily dosing schedule. Dose modifications were permitted. The primary endpoint was clinical benefit rate (CBR). Secondary endpoints included ORR, PFS, overall survival (OS), safety and pharmacokinetics.
Of 12 patients enrolled and treated, all discontinued treatment-the majority (n = 8) owing to disease progression. Most patients were male (n = 8), <65 years of age (n = 11) and had a non-functional tumor (n = 10). The median (range) number of days on drug was 323.5 (22-727). The CBR (95% CI) was 75.0% (42.8-94.5). ORR (95% CI) was 50.0% (21.1-78.9). Median (95% CI) PFS was 16.8 (9.3-26.2) months; however, median (95% CI) OS was not reached (22.0-not estimable). Most common adverse events (AEs; all-causality) were diarrhea (n = 10; 83.3%), hand-foot syndrome (n = 8; 66.7%) and hypertension (n = 8; 66.7%).
These results support the efficacy and safety of sunitinib in Japanese patients with panNETs. Appropriate AE management through dose reduction and interruption may prolong sunitinib treatment and maximize its efficacy.
Palbociclib is a highly selective, reversible, oral inhibitor of cyclin‐dependent kinases 4 and 6 that is approved to treat hormone receptor‐positive/human epidermal growth factor receptor 2‐negative ...advanced breast cancer. An open‐label, single‐arm, Japanese phase 2 study was conducted to investigate the efficacy and safety of palbociclib plus letrozole as first‐line treatment in 42 postmenopausal patients with estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative advanced breast cancer. The probability of progression‐free survival originally reported at 1 year was 75.0% (90% confidence interval, 61.3‐84.4), but median progression‐free survival was not attained at the primary analysis. In this report, updated efficacy and safety results with a longer follow‐up period are presented. The median duration of treatment in the updated analysis was 33.0 months (range, 1.8‐49.2). The probability of progression‐free survival at 1 year was 75.6% (90% confidence interval, 62.4‐84.7). Median progression‐free survival was 35.7 months (95% confidence interval, 21.7‐46.7). Objective response rate and disease control rate were 47.6% (95% confidence interval, 32.0‐63.6) and 85.7% (95% confidence interval, 71.5‐94.6), respectively. Common treatment‐related adverse events (all grades; grade 3/4) were neutropenia (100%; 93%), leukopenia (83%; 60%), and stomatitis (76%; 0%). Treatment‐related febrile neutropenia was reported in one patient. In general, no clinically meaningful deterioration in health‐related quality of life was observed. Palbociclib plus letrozole remained effective and tolerable in Japanese postmenopausal patients with estrogen receptor‐positive, human epidermal growth factor receptor 2‐negative advanced breast cancer in this updated analysis.
With longer follow‐up of an open‐label, single‐arm, Japanese phase 2 study conducted to investigate the efficacy and safety of palbociclib plus letrozole as first‐line treatment in postmenopausal patients with estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative advanced breast cancer, median progression‐free survival was 35.7 months (95% CI, 21.7‐46.7). Palbociclib plus letrozole remained effective and tolerable in Japanese postmenopausal patients with estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative advanced breast cancer.
Background
In the double-blind, phase 3 PALOMA-2 and PALOMA-3 studies, palbociclib plus endocrine therapy (ET) demonstrated significant improvement in progression-free survival versus placebo plus ET ...in patients with hormone receptor‒positive/human epidermal growth factor receptor 2‒negative advanced breast cancer. This analysis assessed subsequent treatment patterns after palbociclib therapy in Japanese patients enrolled in the PALOMA-2 and PALOMA-3 studies.
Methods
PALOMA-2 included postmenopausal women who had not received prior systemic therapy for advanced disease. PALOMA-3 included pre- or postmenopausal women who had progressed on previous ET. Types of subsequent therapy were assessed, and treatment durations of subsequent therapy were estimated using the Kaplan–Meier method.
Results
Japanese patients were enrolled in PALOMA-2 (
n
= 46) and PALOMA-3 (
n
= 35). In both studies, the most common first subsequent therapy was ET (PALOMA-2, 77% in the palbociclib group and 75% in the placebo group; PALOMA-3, 55% and 43%, respectively), followed by chemotherapy (PALOMA-2, 18% and 8%; PALOMA-3, 32% and 57%). The median (95% CI) duration of first subsequent therapy was 6.4 (2.3‒13.9) months with palbociclib plus letrozole and 6.7 (2.8‒13.0) months with placebo plus letrozole in PALOMA-2 and 3.8 (2.4‒5.7) months with palbociclib plus fulvestrant and 9.7 (1.0‒not estimable) months with placebo plus fulvestrant in PALOMA-3.
Conclusions
The types of first subsequent therapy received by Japanese patients in the palbociclib plus ET and placebo plus ET groups were similar. Further evaluation of subsequent therapy data in the real-world setting is warranted considering the small sample size of this analysis.
Background
The cyclin-dependent kinase 4/6 (CDK4/6) inhibitor palbociclib, in combination with endocrine therapy (ET), significantly prolonged progression-free survival in women with hormone ...receptor–positive, human epidermal growth factor receptor 2–negative advanced breast cancer (HR+/HER2− ABC) in PALOMA-2 and PALOMA-3. Neutropenia and palbociclib dose reductions/interruptions occurred more frequently in the Japanese versus overall populations. We evaluated neutropenia patterns, palbociclib dose management, and clinical responses after dose reduction in Japanese patients in PALOMA-2 and PALOMA-3 and a single-arm Japanese phase 2 study.
Methods
PALOMA-2 and the Japanese phase 2 study enrolled postmenopausal women with estrogen receptor–positive, HER2− ABC who had not received prior systemic therapy for advanced disease; PALOMA-3 enrolled women with HR+/HER2− ABC, regardless of menopausal status, whose disease had progressed after prior ET. Palbociclib (125 mg/day) was administered 3 weeks on/1 week off. Dose reduction/interruption, cycle delay, tumor response, and laboratory-assessed neutropenia were analyzed in Japanese patients who received palbociclib.
Results
A total of 101 Japanese patients received palbociclib + ET. Among Japanese patients in the 3 studies, the frequency of all-grade/grade 3/grade 4 neutropenia was 94%/53%/34%, 100%/69%/21%, and 100%/67%/26%, respectively. Twenty (63%), 28 (67%), and 15 (56%) patients required palbociclib dose reduction. Dose interruption or reduction did not affect palbociclib treatment duration, and durable tumor response was observed despite dose reduction.
Conclusion
Neutropenia was manageable with dose modifications, without affecting palbociclib treatment duration or efficacy.
Trial registration
Pfizer (NCT01740427, NCT01684215, NCT01942135).
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