New Drug Development Strategy in Japan: Flexibility in Guideline Adherence.

Recently, a new type of drug lag, known as "drug loss" has emerged in Japan. It is a condition where the development of a drug approved in other countries has not been initiated in Japan. For 265 new drugs approved in the United States or Europe during 2010-2020, only 31% had commenced development in Japan as of December 31, 2020. A characteristic feature of Japanese guidelines on new drug development is that, in principle, clinical trial data in Japanese participants are required in each study phase. Given key players in new drug development are shifting from large pharmaceutical companies to emerging biopharma companies, primarily based outside Japan, the necessity for Japanese data may contribute to the drug lag. This study aimed to clarify the guideline adherence to new drug applications in Japan. Of the 159 new drugs approved in Japan between April 2019 and March 2024, the clinical data packages for almost all drugs included both pharmacokinetic (PK) data and efficacy and safety data in Japanese participants, irrespective of the study phase or design. We identified three flexible development approaches: the absence of Japanese dose-response data (39.6%), absence of Japanese confirmatory data generated from phase III randomized controlled trials (35.2%), and post-hoc Japanese PK data (43.0%, 34/79). Biologics, orphan drug designation, antineoplastic agents, and same applicant and originator were identified as factors significantly associated with these flexibilities. The results will help foreign companies, including emerging biopharmas, in formulating effective new drug development strategies, potentially alleviating the drug lag in Japan.

Age-Specific Dose Regimens of Dexmedetomidine for Pediatric Patients in Intensive Care Following Elective Surgery: A Phase 3, Multicenter, Open-Label Clinical Trial in Japan.

OBJECTIVES: To demonstrate the efficacy, safety, and pharmacokinetics of dexmedetomidine as a potential sedative for pediatric surgery patients in the ICU. DESIGN: Phase 3, multicenter, open-label study. SETTING: This study included 61 patients at 13 tertiary hospitals in Japan. PATIENTS: Pediatric patients (≥ 45 wk corrected gestational age to < 17 yr) undergoing intensive care treatment with mechanical ventilation requiring greater than 6 hours estimated duration of sedation following elective cardiac surgery. INTERVENTIONS: Dexmedetomidine was IV administered without a loading dose at age-specific dose regimens 0.2-1.4 (< 6 yr) and 0.2-1.0 µg/kg/hr (≥ 6 yr). The primary endpoint was the percentage of patients who did not require a rescue sedative (midazolam) infusion during mechanical ventilation or for the first 24 hours of a greater than 24 hours ventilation following the commencement of dexmedetomidine administration. MEASUREMENTS AND MAIN RESULTS: Overall, 47 of the 61 patients (77.0%) did not require rescue midazolam. Adverse events were reported in 53 patients (86.9%). Frequently observed adverse events were hypotension (47.5%), bradycardia (31.1%), and respiratory depression (26.2%). Most of these adverse events were mild, a few moderate, and none severe. Although serious adverse events occurred in four patients, including one cardiac tamponade resulting in the withdrawal of dexmedetomidine, none of the adverse events resulted in mortality or were directly related to dexmedetomidine. The plasma dexmedetomidine concentration generally reached the target concentration of 0.3-1.25 ng/mL at 1-2 hours prior to completion of administration or immediately prior to the commencement of tapering. CONCLUSIONS: The age-specific dose regimens of dexmedetomidine without an initial loading dose achieved an adequate sedation level during mechanical ventilation and caused no clinically significant adverse events in the intensive care pediatric patients. These effects were achieved within the therapeutic range of dexmedetomidine plasma concentration and were accompanied by minimal effects on hemodynamics and respiration.

Tofacitinib for the treatment of moderate to severe chronic plaque psoriasis in Japanese patients: Subgroup analyses from a randomized, placebo-controlled phase 3 trial.

Tofacitinib is an oral Janus kinase inhibitor. These post-hoc analyses assessed tofacitinib efficacy and safety in Japanese patients with psoriasis enrolled in a 52-week global phase 3 study. Patients received tofacitinib 5 mg, tofacitinib 10 mg or placebo twice daily (b.i.d.); placebo-treated patients advanced to tofacitinib at week 16. Primary efficacy end-points were the proportions of patients with 75% or more reduction from baseline Psoriasis Area and Severity Index (PASI-75) and Physician's Global Assessment (PGA) of "clear" or "almost clear" (PGA response) at week 16. Other end-points included: Itch Severity Item (ISI), Dermatology Life Quality Index (DLQI) score and Nail Psoriasis Severity Index (NAPSI). Adverse events (AEs) were recorded throughout the study. Overall, 58 Japanese patients were included in this analysis (tofacitinib 5 mg b.i.d., n = 22; 10 mg b.i.d., n = 24; placebo, n = 12); 29 completed the study. At week 16, significantly more patients receiving tofacitinib 5 and 10 mg b.i.d. versus placebo achieved PASI-75 (50% and 75% vs 0%, P < 0.01) and PGA response (59% and 75% vs 0%, P < 0.001). Substantial improvements in ISI, DLQI and NAPSI score were observed with both tofacitinib doses. Over 52 weeks, similar rates of AEs were reported across treatment groups; one serious AE occurred with tofacitinib 10 mg b.i.d. Herpes zoster occurred in three patients receiving tofacitinib 10 mg b.i.d. No deaths, serious infections, malignancies or gastrointestinal perforations were reported. Results were generally consistent with global analysis, suggesting sustained efficacy and a manageable safety profile, with increased herpes zoster incidence, of tofacitinib in Japanese patients with psoriasis.

Is antipsychotic polypharmacy associated with metabolic syndrome even after adjustment for lifestyle effects?: a cross-sectional study.

BACKGROUND: Although the validity and safety of antipsychotic polypharmacy remains unclear, it is commonplace in the treatment of schizophrenia. This study aimed to investigate the degree that antipsychotic polypharmacy contributed to metabolic syndrome in outpatients with schizophrenia, after adjustment for the effects of lifestyle. METHODS: A cross-sectional survey was carried out between April 2007 and October 2007 at Yamanashi Prefectural KITA hospital in Japan. 334 patients consented to this cross-sectional study. We measured the components consisting metabolic syndrome, and interviewed the participants about their lifestyle. We classified metabolic syndrome into four groups according to the severity of metabolic disturbance: the metabolic syndrome; the pre-metabolic syndrome; the visceral fat obesity; and the normal group. We used multinomial logistic regression models to assess the association of metabolic syndrome with antipsychotic polypharmacy, adjusting for lifestyle. RESULTS: Seventy-four (22.2%) patients were in the metabolic syndrome group, 61 (18.3%) patients were in the pre-metabolic syndrome group, and 41 (12.3%) patients were in visceral fat obesity group. Antipsychotic polypharmacy was present in 167 (50.0%) patients. In multinomial logistic regression analyses, antipsychotic polypharmacy was significantly associated with the pre-metabolic syndrome group (adjusted odds ratio [AOR], 2.348; 95% confidence interval [CI], 1.181-4.668), but not with the metabolic syndrome group (AOR, 1.269; 95%CI, 0.679-2.371). CONCLUSIONS: These results suggest that antipsychotic polypharmacy, compared with monotherapy, may be independently associated with an increased risk of having pre-metabolic syndrome, even after adjusting for patients' lifestyle characteristics. As metabolic syndrome is associated with an increased risk of cardiovascular mortality, further studies are needed to clarify the validity and safety of antipsychotic polypharmacy.

Intraosseous delivery of paclitaxel-loaded hydroxyapatitealginate composite beads delaying paralysis caused by metastatic spine cancer in rats.

OBJECT: Bone is frequently the first site and the only site of breast cancer at recurrence. Local control is important especially for metastatic spine cancer, because epidural spinal cord compression is significantly associated with the quality of life and survival of these patients. The authors have developed a local delivery system of paclitaxel in the form of hydroxyapatite-alginate composite beads. This study was conducted to clarify the therapeutic effect in a rat model of metastatic spine cancer. METHODS: Twenty-one rats with metastatic spine cancer were divided into 3 groups: a local treatment group (6 rats), a systemic treatment group (9 rats), and a control group (6 rats). The hind-limb motor function of the animals was monitored daily by using the Basso-Beattie-Bresnahan scale. The authors monitored the disease-free time and survival times. The log-rank test was used to define statistically significant differences between the 3 groups. RESULTS: The animals in the control group developed hind-limb paralysis at a mean of 10.8 days and died at a mean of 16.0 days. The animals treated with 2.4 wt% of paclitaxel-loaded hydroxyapatite-alginate composite beads (the local treatment group) showed a 140-150% increase in the disease-free time and survival time compared with that of the control group. Although an approximately 30-fold higher dosage of paclitaxel was administered, the therapeutic effect was not evident in the systemic treatment group. CONCLUSIONS: Intraosseous delivery of paclitaxel-loaded hydroxyapatite-alginate composite beads delayed paralysis caused by metastatic spine cancer in rats. The results indicate that intraosseous chemotherapy may provide an effective local treatment of metastatic spine cancer.