The safety, tolerability and pharmacokinetics of niraparib in Japanese patients with solid tumours: results of a phase I dose-escalation study.

BACKGROUND: Niraparib is the only poly (adenosine diphosphate-ribose)-polymerase (PARP) inhibitor available as oral monotherapy for maintenance, regardless of BRCA mutational status. METHODS: This phase I, open-label, non-randomized, dose-escalation study was conducted in Japan using a 3 + 3 design. Adults (≥20 years) with metastatic or locally advanced solid tumours were enrolled. Niraparib 200 mg (cohort 1) or 300 mg (cohort 2) was administered once daily in 21-day cycles (no drug holiday between cycles) until progressive disease (PD) or unacceptable toxicity. The primary objective was to evaluate the safety and tolerability of niraparib in Japanese patients with advanced solid tumours. The number of patients with dose-limiting toxicities in cycle 1 and number with treatment-emergent adverse events were primary endpoints. Secondary endpoints were pharmacokinetics and tumour response. RESULTS: There were three patients in cohort 1 and six patients in cohort 2. Only one patient, in cohort 2, developed a dose-limiting toxicity (grade 4 platelet count decreased). All patients in both cohorts developed treatment-emergent adverse events. The most common treatment-related treatment-emergent adverse events were decreased appetite (n = 2) in cohort 1, and platelet count decreased as well as aspartate aminotransferase increased (both n = 5) in cohort 2. Mean Cmax and AUC0-24 of niraparib increased dose-proportionally after multiple doses (accumulation ratio of between 1.64 and 3.65); median tmax was 3-4 h. Two patients, both in cohort 2, had a partial response to treatment. CONCLUSIONS: Niraparib (200 or 300 mg/day) was tolerable and had a favourable pharmacokinetic profile in Japanese patients with advanced solid tumours.

Phase 2 single-arm study on the safety of maintenance niraparib in Japanese patients with platinum-sensitive relapsed ovarian cancer.

OBJECTIVE: The primary objective of this study was to evaluate the safety of niraparib 300 mg/day in Japanese patients with platinum-sensitive, relapsed ovarian cancer in a maintenance setting. METHODS: Phase 2, multicenter, open-label, single-arm study enrolled Japanese patients with platinum-sensitive, relapsed ovarian cancer who had received ≥2 platinum-based regimens. The primary endpoint (incidence of grade 3 or 4 thrombocytopenia-related events within 30 days after initial niraparib administration) was justified by the incidences of a global pivotal phase 3 study and its post-hoc safety analysis on thrombocytopenia, the major hematological adverse event of niraparib. The overall safety analysis examined other treatment-emergent adverse events (TEAEs). RESULTS: Enrolled patients (n=19) had a median (min, max) body weight of 53.9 (40.8-79.1) kg; all but one patient weighed <77 kg. Most (94.7%) patients initially received niraparib 300 mg/day but this decreased in subsequent cycles (mean±standard deviation dose intensity, 191.6±65.7 mg/day). In total, 6/19 (31.6%) patients experienced grade 3 or 4 thrombocytopenia-related events within 30 days of initial niraparib administration. Other common TEAEs included nausea, and decreased platelet or neutrophil counts. No progression-free or overall survival events occurred; only 1 of 4 response-evaluable patients had a post-baseline tumor assessment (stable disease). CONCLUSION: The incidence of grade 3 or 4 thrombocytopenia-related events in Japanese ovarian cancer patients was similar to that in the corresponding non-Japanese study. Overall, the safety profile was acceptable and consistent with the known safety profile and previous experience with niraparib. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03759587.

Phase 2 single-arm study on the efficacy and safety of niraparib in Japanese patients with heavily pretreated, homologous recombination-deficient ovarian cancer.

OBJECTIVE: To evaluate the efficacy and safety of niraparib in Japanese women with heavily pretreated ovarian cancer. METHODS: This Phase 2 open-label, single-arm study enrolled Japanese women with homologous recombination deficiency-positive relapsed, high-grade serous ovarian, fallopian tube, or primary peritoneal cancer who had completed 3-4 lines of therapy. The starting dose of niraparib was 300 mg administered once daily in continuous 28-day cycles until objective progressive disease, unacceptable toxicity, consent withdrawal or discontinuation. The primary endpoint, objective response rate (ORR), was assessed by the investigator using RECIST version 1.1. Safety evaluations included the incidence of treatment-emergent adverse events (TEAEs), including serious TEAEs. RESULTS: Twenty women were enrolled and the confirmed ORR in the full analysis set (FAS) was 35.0% (7/20), consisting of 1 complete response and 6 partial responses. Disease control rate in the FAS was 90.0%. The most frequently reported TEAEs (>50%) were anemia, nausea, and platelet count decreased. One patient (5.0%) had TEAEs leading to discontinuation of niraparib whereas reductions or interruptions were reported in 14 (70.0%) and 15 (75.0%) patients, respectively. The median dose intensity (202.9 mg daily) corresponded to a relative dose intensity of 67.6%. CONCLUSION: Efficacy and safety of niraparib in heavily pretreated Japanese women was comparable to that seen in an equivalent population of non-Japanese women. No new safety signals were identified. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03759600.

Efficacy and safety of leuprorelin acetate 6-month depot, TAP-144-SR (6M), in combination with tamoxifen in postoperative, premenopausal patients with hormone receptor-positive breast cancer: a phase III, randomized, open-label, parallel-group comparative study.

BACKGROUND: Leuprorelin acetate, a luteinizing hormone-releasing hormone agonist, is used worldwide in premenopausal women with hormone receptor-positive breast cancer. This study was conducted to assess the non-inferiority of the 6-month depot formulation, TAP-144-SR (6M) 22.5 mg to the 3-month depot formulation, TAP-144-SR (3M) 11.25 mg in postoperative, premenopausal patients with hormone receptor-positive breast cancer. METHODS: This was a 96-week phase III, randomized, open-label, parallel-group comparative study. All patients concomitantly received oral tamoxifen (20 mg daily). The primary endpoint was the suppression rate of serum estradiol (E2) to the menopausal level (≤30 pg/mL) from Week 4 through Week 48. RESULTS: In total, 167 patients were randomized to receive TAP-144-SR (6M) (n = 83) or TAP-144-SR (3M) (n = 84) and the E2 suppression rate was 97.6 and 96.4 %, respectively. The estimated between-group difference was 1.2 % (95 % confidence interval -5.2 to 7.8). The non-inferiority of TAP-144-SR (6M) to TAP-144-SR (3M) for E2 suppression was confirmed. As for safety, common adverse events were hot flush and injection site reactions including induration, pain, and erythema in both treatment groups, which were of ≤Grade 2 in severity and not serious. No significant between-group differences in safety profiles and tolerability were observed. CONCLUSIONS: TAP-144-SR (6M) was not inferior to TAP-144-SR (3M) for its suppressive effect on serum E2. TAP-144-SR (6M) was also as well tolerated as TAP-144-SR (3M).

Randomized, double-blind, phase III study to evaluate the efficacy and safety of once-daily treatment with alogliptin and metformin hydrochloride in Japanese patients with type 2 diabetes.

This randomized, double-blind, phase III study evaluated the efficacy and safety of once-daily treatment with alogliptin (25 mg once daily), alone or with metformin hydrochloride (500 mg once daily or 250 mg twice daily), in Japanese patients with type 2 diabetes. The primary endpoint was change in glycated haemoglobin (HbA1c) from baseline to the end of treatment (week 24). The least squares (LS) mean (standard error) change in HbA1c from baseline to the end of treatment (week 24) was 0.16 (0.072)% in alogliptin alone, -0.49 (0.049)% in alogliptin/metformin once daily, and -0.60 (0.049)% in alogliptin/metformin twice daily. The LS mean difference in HbA1c change from baseline between alogliptin/metformin once daily and alogliptin alone (alogliptin/metformin once daily minus alogliptin alone) was -0.65% (95% confidence interval [CI] -0.821, -0.480) and between alogliptin/metformin once daily and twice daily (once daily minus twice daily) was 0.11% (95% CI -0.026, 0.247). The overall frequency of adverse events was similar among the groups. This study showed that the efficacy of alogliptin/metformin once daily was superior to alogliptin alone and non-inferior to alogliptin/metformin twice daily, and that alogliptin/metformin once daily was safe and well tolerated in Japanese patients with type 2 diabetes.