Increased risk of hypocalcemia with decreased kidney function in patients prescribed bisphosphonates based on real-world data from the MID-NET® in Japan: a new-user cohort study.

BACKGROUND: In the post-marketing stage, cases of hypocalcemia associated with bisphosphonate preparations (BPs) have been reported in patients with decreased kidney function, despite warning against use of BPs in such patients in the package insert (PI) of Japan. The purpose of this study was to investigate the safety of BPs in patients with decreased kidney function. METHODS: The cohort study was conducted in patients with osteoporosis and newly prescribed bisphosphonate utilizing real-world data from MID-NET® in Japan. The adjusted hazard ratios (aHRs) for hypocalcemia (a corrected serum Ca level < 8.00 mg/dL) relative to the normal group were calculated in each decreased kidney function group (mild, moderate or severe group). RESULTS: A total of 14,551 patients were included in the analysis, comprising 2,601 (17.88%) with normal (eGFR ≥ 90 mL/min/1.73m2), 7,613 (52.32%) with mild (60 ≤ eGFR < 90 mL/min/1.73m2), 3,919 (26.93%) with moderate (30 ≤ eGFR < 60 mL/min/1.73m2), and 418 (2.87%) with severe kidney function (eGFR < 30 mL/min/1.73m2). The aHRs (95% confidence interval) for hypocalcemia were 1.85 (0.75-4.57), 2.30 (0.86-6.21), and 22.74 (8.37-61.78) in the mild, moderate, and severe groups, respectively. The increased risk of hypocalcemia depending on kidney function was also observed even when calculating the aHR for each specific BP such as alendronate sodium hydrate, minodronic acid hydrate, and sodium risedronate hydrate. Furthermore, similar results were obtained in the sensitivity analysis by altering the outcome definition to a 20% or more reduction in corrected serum Ca level from the baseline, as well as when focusing on patients with more than one laboratory test result per 30 days during the follow-up period. CONCLUSIONS: These findings suggest that the risk of hypocalcemia during BP prescription is higher in patients with decreased kidney function, particularly those with severely decreased kidney function. The quantitative real-world evidence on the safety risk of BPs obtained in this study has led to the PI revision describing a relationship between hypocalcemia risk and decreased kidney function as a regulatory action in Japan and will contribute to promoting the proper use of BPs with appropriate risk management in clinical practice.

Recent Status of Phase I Clinical Trials for Brain Tumors: A Regulatory Science Study of Exploratory Efficacy Endpoints.

BACKGROUND: Appropriate exploratory efficacy data from Phase I trials are vital for subsequent phases. Owing to the uniqueness of brain tumors (BTs), use of different strategies to evaluate efficacy is warranted. We studied exploratory efficacy evaluation in Phase I trials involving BTs. METHODS: Using Clarivate's Cortellis™, 42 Phase I trials of BT interventions conducted from 2020 to 2022 were analyzed for efficacy endpoints, which were set as primary endpoints (PEs) or secondary endpoints (SEs). Additionally, these metrics were compared in two subgroups: trials including only BTs (Group-A) and those including BTs among mixed solid tumors (Group-B). RESULTS: Selected studies included a median of 1.5 PEs (range, 1-6) and 5 SEs (range, 0-19). Efficacy endpoints were included as PEs and SEs in 2 (5%) and 31 (78%) trials, respectively. Among the latter 31 trials that included 94 efficacy endpoints, 24, 22, 20, 9, and 8 reflected overall response rate (ORR), progression-free survival (PFS), overall survival (OS), duration of response (DOR), and disease control rate (DCR), respectively. ORR for BT was determined using various methods; however, the Response Evaluation Criteria in Solid Tumors (RECIST) was used less frequently in Group-A than in Group-B (p = 0.0039). CONCLUSIONS: Recent Phase I trials included efficacy endpoints as SEs, with ORR, PFS, or OS included in ~ 50% trials and DOR or DCR in ~ 25%. No established criteria exist for imaging evaluation of BTs. Phase I trials involving mixed solid tumor cohorts revealed challenges in designing methods to assess the exploratory efficacy of BTs.

Lower Risks of Gastrointestinal Perforation and Intestinal Obstruction in Patients with Atypical Antipsychotics in Comparison with Typical Antipsychotics Based on Real-World Data from the MID-NET® in Japan.

Intestinal perforation and obstruction are known to be one of the adverse events caused by antipsychotics; however, warning information on package inserts varies among antipsychotics. To investigate the risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics compared with those in patients prescribed typical antipsychotics, a nested case-control study was conducted utilizing real-world data from the MID-NET® medical information database in Japan. The study period spanned from January 1, 2009, to December 31, 2018. We found that the risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics were significantly lower than those in patients prescribed typical antipsychotics (adjusted odds ratio, 0.48; 95% confidence interval, 0.29-0.80). This finding was supported with prolonged periods for the exposure definition in the sensitivity analyses. In addition, no major differences in the risks of atypical antipsychotics, such as risperidone, quetiapine, olanzapine, and aripiprazole, were identified in this study. The safety profile regarding the lower risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics should be considered when choosing antipsychotics in clinical practice in terms of the proper use of such drugs.

Structure and Function of Gli123 Involved in Mycoplasma mobile Gliding.

Mycoplasma mobile is a fish pathogen that glides on solid surfaces by means of its own gliding machinery composed of internal and surface structures. In the present study, we focused on the function and structure of Gli123, a surface protein that is essential for the localization of other surface proteins. The amino acid sequence of Gli123, which is 1,128 amino acids long, contains lipoprotein-specific repeats. We isolated the native Gli123 protein from M. mobile cells and a recombinant protein, rGli123, from Escherichia coli. The isolated rGli123 complemented a nonbinding and nongliding mutant of M. mobile that lacked Gli123. Circular dichroism and rotary-shadowing electron microscopy (EM) showed that rGli123 has a structure that is not significantly different from that of the native protein. Rotary-shadowing EM suggested that Gli123 adopts two distinct globular and rod-like structures, depending on the ionic strength of the solution. Negative-staining EM coupled with single-particle analysis revealed that Gli123 forms a globular structure featuring a small protrusion with dimensions of approximately 15.7, 14.7, and 14.1 nm for the "height," major axis and minor axis, respectively. Small-angle X-ray scattering analyses indicated a rod-like structure composed of several tandem globular domains with total dimensions of approximately 34 nm in length and 6 nm in width. Both molecular structures were suggested to be dimers, based on the predicted molecular size and structure. Gli123 may have evolved by multiplication of repeating lipoprotein units and acquired a role for Gli521 and Gli349 assembly. IMPORTANCE Mycoplasmas are pathogenic bacteria that are widespread in animals. They are characterized by small cell and genome sizes but are equipped with unique abilities for infection, such as surface variation and gliding. Here, we focused on a surface-localizing protein named Gli123 that is essential for Mycoplasma mobile gliding. This study suggested that Gli123 undergoes drastic conformational changes between its rod-like and globular structures. These changes may be caused by a repetitive structure common in the surface proteins that is responsible for the modulation of the cell surface structure and related to the assembly process for the surface gliding machinery. An evolutionary process for surface proteins essential for this mycoplasma gliding was also suggested in the present study.

Characterizing Granulocytopenia Associated with Thiamazole in Patients with Hyperthyroidism Based on Real-World Data from the MID-NET in Japan.

Despite the requirement of routine blood tests during thiamazole treatment in Japan, granulocytopenia among patients treated with thiamazole has been occasionally reported to the Pharmaceuticals and Medical Devices Agency (PMDA). To characterize granulocytopenia in patients with thiamazole in Japan, the effects of routine blood tests were examined in a cohort of new users of thiamazole or propylthiouracil utilizing the MID-NET. The occurrence of granulocytopenia (neutrophil count ≤ 1,500/µL) in a given period was compared between patients with and without blood test results prior to the period. The trend in neutrophil count during thiamazole treatment was also compared between patients with and without granulocytopenia. A nested case-control study based on the cohort was conducted to identify potential risk factors for granulocytopenia during thiamazole treatment. In the new user cohort including 4,371 patients treated with thiamazole, the occurrence of granulocytopenia in patients who had undergone blood tests at all previous periods was similar or higher than that among those who had not undergone blood test in all previous periods (e.g., adjusted odds ratio in period 2 was 1.63). The neutrophil count was relatively lower in the group of patients with granulocytopenia even before the occurrence of granulocytopenia. In a nested case-control study, an upward tendency of the risk was observed when a patient was co-prescribed anti-arrhythmic drugs or antiulcer drugs with thiamazole. The characteristics of granulocytopenia during thiamazole treatment elucidated in this study should be recognized in clinical practice for the proper use of thiamazole.

Efficacy Endpoints in Phase II Clinical Trials for Meningioma: An Analysis of Recent Clinical Trials.

BACKGROUND: Response Evaluation Criteria in Solid Tumors (RECIST)-based response rates are commonly used as efficacy endpoints in phase II clinical trials for solid tumors. However, no consensus has been reached concerning adequate efficacy endpoints for phase II clinical trials targeting meningioma. Irregularity of lesions after resection, and varying degrees of dysplasia and histologic subtypes make establishing an appropriate efficacy evaluation difficult. METHODS: We analyzed primary efficacy endpoints (PEEs) and background factors from 48 trials retrieved from ClinicalTrials.gov ( https://clinicaltrials.gov/ ) using the search criteria "meningioma," "interventional," "phase II," and "study start 4/1/2001 to 3/31/2021." Primary purpose of the study was efficacy endpoint setting in overall population and three subgroups. RESULTS: Among 45 PEEs set in the 39 trials included; 33 trials with single PEE, and six trials with double PEEs, 17/45 (38%) trials adopted progression-free survival (PFS) rate, 15/45 (33%) trials response rate (seven Macdonald criteria or modified, three RECIST, three volumetric estimation, one RANO criteria, one unknown), 10/45 (22%) PFS, 1/45 (2%) OS, and 2/45 (4%) other endpoints. Although 26 PEEs were time-to-event endpoints, 19 of the 26 PEEs were single-arm studies. CONCLUSIONS: Time-to-event efficacy endpoints were often compared to historical data, and two-dimensional evaluation is more suitable than one-dimensional one. Accumulation of prognostic data is essential to standardize time-to-event efficacy endpoints. Considering the difficulty of setting design for phase II clinical studies targeting meningioma, evaluation might be done with multiple efficacy endpoints.

HARmonized Protocol Template to Enhance Reproducibility of hypothesis evaluating real-world evidence studies on treatment effects: A good practices report of a joint ISPE/ISPOR task force.

PROBLEM: Ambiguity in communication of key study parameters limits the utility of real-world evidence (RWE) studies in healthcare decision-making. Clear communication about data provenance, design, analysis, and implementation is needed. This would facilitate reproducibility, replication in independent data, and assessment of potential sources of bias. WHAT WE DID: The International Society for Pharmacoepidemiology (ISPE) and ISPOR-The Professional Society for Health Economics and Outcomes Research (ISPOR) convened a joint task force, including representation from key international stakeholders, to create a harmonized protocol template for RWE studies that evaluate a treatment effect and are intended to inform decision-making. The template builds on existing efforts to improve transparency and incorporates recent insights regarding the level of detail needed to enable RWE study reproducibility. The overarching principle was to reach for sufficient clarity regarding data, design, analysis, and implementation to achieve 3 main goals. One, to help investigators thoroughly consider, then document their choices and rationale for key study parameters that define the causal question (e.g., target estimand), two, to facilitate decision-making by enabling reviewers to readily assess potential for biases related to these choices, and three, to facilitate reproducibility. STRATEGIES TO DISSEMINATE AND FACILITATE USE: Recognizing that the impact of this harmonized template relies on uptake, we have outlined a plan to introduce and pilot the template with key international stakeholders over the next 2 years. CONCLUSION: The HARmonized Protocol Template to Enhance Reproducibility (HARPER) helps to create a shared understanding of intended scientific decisions through a common text, tabular and visual structure. The template provides a set of core recommendations for clear and reproducible RWE study protocols and is intended to be used as a backbone throughout the research process from developing a valid study protocol, to registration, through implementation and reporting on those implementation decisions.

Descriptive Analysis for the Trend of Pharmacovigilance Planning in Risk Management Plans on New Drugs Approved During 2016-2019.

BACKGROUND: Japanese pharmaceutical authorities have conducted regulatory renovations of pharmacovigilance planning (PVP) since implementing new procedures for developing post-marketing study plans in 2018 in order to promote more focused and scientific approaches. This study aimed to descriptively assess the effects of those regulatory renovations on PVP for new drugs in Japan. METHODS: We identified PVP information (drug characteristics, efficacy and safety issues, and additional activities) from the first version of risk management plans for new drugs approved between 2016 and 2019. The following indicators were analyzed: (1) proportion of the number of drugs with at least one efficacy issue among all the drugs, (2) proportion of the number of safety issues with additional activity among all the safety issues, and (3) proportion of database studies among all additional activities. RESULTS: In total, 168 drugs, 1212 safety issues, and 301 additional activities were identified. The proportion of drugs with at least one efficacy issue decreased from 91.4% in 2016 to 27.3% in 2019, and the proportion of safety issues with additional activity also decreased from 93.9% in 2016 to 53.7% in 2019. In contrast, the proportion of database studies increased from 0 to 19.2%. The percentages of additional activities targeting important identified and potential risks also gradually decreased during the 4-year period. CONCLUSION: Notable changes in the three indicators during 2016-2019 were observed, which suggests that regulatory renovation has affected PVP in Japan.

HARmonized Protocol Template to Enhance Reproducibility of Hypothesis Evaluating Real-World Evidence Studies on Treatment Effects: A Good Practices Report of a Joint ISPE/ISPOR Task Force.

OBJECTIVES: Ambiguity in communication of key study parameters limits the utility of real-world evidence (RWE) studies in healthcare decision-making. Clear communication about data provenance, design, analysis, and implementation is needed. This would facilitate reproducibility, replication in independent data, and assessment of potential sources of bias. METHODS: The International Society for Pharmacoepidemiology (ISPE) and ISPOR-The Professional Society for Health Economics and Outcomes Research (ISPOR) convened a joint task force, including representation from key international stakeholders, to create a harmonized protocol template for RWE studies that evaluate a treatment effect and are intended to inform decision-making. The template builds on existing efforts to improve transparency and incorporates recent insights regarding the level of detail needed to enable RWE study reproducibility. The over-arching principle was to reach for sufficient clarity regarding data, design, analysis, and implementation to achieve 3 main goals. One, to help investigators thoroughly consider, then document their choices and rationale for key study parameters that define the causal question (e.g., target estimand), two, to facilitate decision-making by enabling reviewers to readily assess potential for biases related to these choices, and three, to facilitate reproducibility. STRATEGIES TO DISSEMINATE AND FACILITATE USE: Recognizing that the impact of this harmonized template relies on uptake, we have outlined a plan to introduce and pilot the template with key international stakeholders over the next 2 years. CONCLUSION: The HARmonized Protocol Template to Enhance Reproducibility (HARPER) helps to create a shared understanding of intended scientific decisions through a common text, tabular and visual structure. The template provides a set of core recommendations for clear and reproducible RWE study protocols and is intended to be used as a backbone throughout the research process from developing a valid study protocol, to registration, through implementation and reporting on those implementation decisions.

Analysis and enhancement of risk management for ethnic differences in antineoplastic drugs in Japan.

BACKGROUND: Risk management in the post-marketing phase is crucial to minimize health problems caused by drugs. Because ethnic factors may affect drug safety, the objective of this study was to explore concrete approaches to reflecting ethnic factors in risk management under multi-regional drug development. METHODS: We assessed Pharmaceuticals and Medical Devices Agency (PMDA) review reports on antineoplastic drugs approved as new molecular entities in the last 10 years to identify any differences in the incidence of adverse drug reactions (ADRs) related to myelosuppression, hepatic impairment, renal impairment, and interstitial lung disease between Japanese and non-Japanese populations. In addition, we investigated how those ADRs were handled in the labeling of each drug. RESULTS: In total, 44 drugs were available for comparing the incidence of ADRs between Japanese and non-Japanese populations. Of these, 32 drugs had a higher incidence of ADRs in the Japanese population. However, the incidence of ADRs in the Japanese population was described in the labeling for 7 drugs, and only the incidence in the overall population in multi-regional phase III trials was described in the labeling for the remaining 25 drugs. Of these 25 drugs, two drugs were immediately placed under emergency safety control measures after approval because of the high incidence of ADRs in Japanese patients. CONCLUSIONS: For drugs that might cause serious ADRs and with a higher incidence in the Japanese population, information should be provided on the incidence in the Japanese population as well as in the overall population.

Transcatheter aortic valve implantation under lower activated clotting time in a patient with hemorrhagic gastric cancer: a case report.

BACKGROUND: Perioperative management of transcatheter aortic valve implantation (TAVI) in patients with a high risk of bleeding requires careful consideration. CASE PRESENTATION: A 74-year-old man complained of chest pain and was admitted to our hospital. Close examination revealed severe aortic stenosis (AS) and hemorrhagic gastric cancer. Hemorrhage from gastric cancer was controlled using endoscopic hemostasis. While both gastric cancer and AS required surgery, we decided to perform transfemoral transcatheter aortic valve implantation (TAVI) under monitored anesthesia. To reduce bleeding from gastric cancer, we carefully adjusted the heparin dose to maintain the activated clotting time (ACT) between 180 and 200 s. TAVI with a balloon-expandable valve was completed without thrombotic complications. Laparoscopic distal gastrectomy was performed on the 6th day after TAVI. CONCLUSIONS: We report the successful management of TAVI in a patient with hemorrhagic gastric cancer. In TAVI for patients with hemorrhagic diseases, careful consideration of antithrombotic therapy is required.

Assessing the Risk of Decrease in Kidney Function in Patients Prescribed Direct-Acting Antivirals for Hepatitis C Utilizing the MID-NET® Medical Information Database Network in Japan.

An association between kidney disease and direct-acting antivirals against hepatitis C (DAAs) has been suggested, however the warning on the package insert (PI) of the drug varies among DAAs. In this study, the risk of decreased kidney function associated with DAAs marketed in Japan was investigated to determine whether the risk of kidney disease is a common adverse event and class effect of DAAs. Data for patients who were new users of DAAs marketed in Japan, with eGFR ≥ 45 mL/min/1.73 m2 and without specific risk factors, were extracted from the MID-NET® medical information database network in Japan. Changes from the baseline on estimated glomerular filtration rate (eGFR) categories (eGFR ≥ 90, 90 > eGFR ≥ 60, 60 > eGFR ≥ 45, 45 > eGFR ≥ 30, 30 > eGFR ≥ 15, 15 > eGFR; unit: mL/min/1.73 m2) were used for evaluating the risk of decreased kidney function. Exposure groups for DAAs and relevant concomitant drugs were categorized into 10 patterns based on the PI. Among the 10 patterns, a significant increase in the incidence rate ratio (P < 0.01) was observed in the prescription patterns of concomitant use of telaprevir with peginterferon alpha and ribavirin, concomitant use of daclatasvir hydrochloride with asunaprevir, and ombitasvir hydrate combined with paritaprevir hydrate and ritonavir, which were concomitantly used with ribavirin; such an increase was not observed in the other prescription patterns. The effects of DAAs on kidney function may differ among drugs, suggesting the possibility that the risk of kidney disease is not a class effect of DAAs and should be evaluated individually for each DAA.

Validity of identification algorithms combining diagnostic codes with other measures for acute ischemic stroke in MID-NET®.

PURPOSE: We aimed to develop a reliable identification algorithm combining diagnostic codes with several treatment factors for inpatients with acute ischemic stroke (AIS) to conduct pharmacoepidemiological studies using the administrative database MID-NET® in Japan. METHODS: We validated 11 identification algorithms based on 56 different diagnostic codes (International Classification of Diseases, Tenth Revision; ICD-10) using Diagnosis Procedure Combination (DPC) data combined with information on AIS therapeutic procedures added as "AND" condition or "OR" condition. The target population for this study was 366 randomly selected hospitalized patients with possible cases of AIS, defined as relevant ICD-10 codes and diagnostic imaging and prescription or surgical procedure, in three institutions between April 1, 2015 and March 31, 2017. We determined the positive predictive values (PPVs) of these identification algorithms based on comparisons with a gold standard consisting of chart reviews by experienced specialist physicians. Additionally, the sensitivities of them among 166 patients with the possible cases of AIS at a single institution were evaluated. RESULTS: The PPVs were 0.618 (95% confidence interval [CI]: 0.566-0.667) to 0.909 (95% CI: 0.708-0.989) and progressively increased with adding or limiting information on AIS therapeutic procedures as "AND" condition in the identification algorithms. The PPVs for identification algorithms based on diagnostic codes I63.x were >0.8. However, the sensitivities progressively decreased to a maximum of ~0.2 after adding information on AIS therapeutic procedures as "AND" condition. CONCLUSIONS: The identification algorithms based on the combination of appropriate ICD-10 diagnostic codes in DPC data and other AIS treatment factors may be useful to studies for AIS at a national level using MID-NET®.

Thoracoscopic infrared ablation to create a box lesion as a treatment for atrial fibrillation.

BACKGROUND: Creating a box lesion in the posterior wall of the left atrium from the epicardial side of the beating heart remains a challenge. Although a transmural lesion can be created by applying radiofrequency (RF) energy at clampable sites, it is still difficult to create a transmural lesion at unclampable sites because the inner blood flow in the unclampable free wall weakens the thermal effect on the outside. Our aim was to apply the newly developed infrared coagulator to create linear transmural lesions on the beating heart thoracoscopically to treat atrial fibrillation (AF). CASE PRESENTATION: A 71-year-old male was referred to our hospital with a diagnosis of hypertrophic cardiomyopathy and permanent atrial fibrillation. The patient was first diagnosed with atrial fibrillation 20 years before. Direct current cardioversion had been performed every few years a total of four times, but sinus rhythm restoration had always been temporary. On February 27, 2020, thoracoscopic PV isolation together with infrared roof- and bottom-line ablation to create a box lesion and left atrial appendage amputation (LAAA) were performed. The coagulator could be applied to clinical thoracoscopic surgery to successfully create a box lesion without any complication. The patient restored a regular sinus rhythm, it has been maintained for eleven months, and there have been no adverse events. CONCLUSIONS: The infrared coagulator might have enough potential to create transmural lesions on the beating heart in thoracoscopic AF surgery.

Evolving Acceptance and Use of RWE for Regulatory Decision Making on the Benefit/Risk Assessment of a Drug in Japan.

There is growing interest in the utilization of real-world data (RWD) and real-world evidence (RWE) for regulatory purposes. However, there are challenges in the practical utilization of RWD to provide RWE as a basis for regulatory decision making. This article presents the regulatory initiatives in Japan and efforts taken to promote the utilization of RWD/RWE for regulatory decision making at the pre- and postapproval stages of a drug. There has been a rapid increase in the number of RWD cases evaluated for drug safety assessment in Japan. Nevertheless, more regulatory experiences and considerations are necessary for the utilization of RWD in the efficacy evaluation of a drug. Based on past experiences, data reliability and appropriateness of the methodology for analysis are the major discussion points in utilizing RWD and RWE for regulatory decision making. International harmonization of regulatory requirements is another important area in utilizing RWD and sharing the RWE globally. We describe our perspective on providing RWE, which is useful for regulatory decision making throughout a drug's life cycle.

Oral acetaminophen-induced spinal 5-hydroxytriyptamine release produces analgesic effects in the rat formalin test.

The mechanism by which acetaminophen produces its analgesic effects is not fully understood. One possible mechanism is the activation of the spinal 5-hydroxytryptamine (5-HT) receptor, although direct evidence of spinal 5-HT release has not yet been reported. N-arachidonoylphenolamine (AM404), a metabolite of acetaminophen, is believed to be the key substance that contributes to the analgesic effects of acetaminophen. In this study, we examined whether acetaminophen and AM404 induce spinal 5-HT release and the mechanism through which spinal 5-HT receptor activation exerts analgesic effects in a rat formalin test in an inflammatory pain model. Spinal 5-HT release was examined by intrathecal microdialysis in conscious and freely moving rats. Acetaminophen was administered orally, and AM404 was administered intracerebroventricularly. In rat formalin tests, oral acetaminophen and intracerebroventricular AM404 induced significant spinal 5-HT release and produced analgesic effects. The analgesic effect of oral acetaminophen was partially antagonized by intrathecal administration of WAY100135 (a 5-HT1A receptor antagonist) and SB269970 (a 5-HT7 receptor antagonist). In contrast, the analgesic effect of intracerebroventricular AM404 was completely antagonized by WAY100135, while SB269970 had no effect. Our data suggest that while oral acetaminophen and intracerebroventricular AM404 activate the spinal 5-HT system, the role of the spinal 5-HT system activated by oral acetaminophen differs from that activated by intracerebroventricular AM404.

Analgesic characteristics of a newly developed α2δ ligand, mirogabalin, on inflammatory pain.

Mirogabalin is a novel α2δ ligand approved in Japan for the treatment of peripheral neuropathic pain. However, the sites of action of α2δ ligands to produce analgesic effects on inflammatory pain remain unclear. In this study, we investigated the analgesic effect and site of action of mirogabalin using the rat formalin test, an acute inflammatory pain model. Mirogabalin was administered orally, intrathecally, and intracerebroventricularly. Open field tests were performed to evaluate the effect of oral-, intrathecally, and intracerebroventricularly administered mirogabalin on locomotor activity and orientation ability. Oral mirogabalin produced an analgesic effect when the formalin test was performed 4 h, but not 1 or 2 h, after oral administration. Intrathecal, but not intracerebroventricular, administration of mirogabalin produced analgesic effects when mirogabalin was administered 10 min before formalin injection. These analgesic effects were not antagonized by idazoxan, an α2 adrenergic antagonist; WAY100135, a 5-HT1A antagonist; or naloxone, an opioid receptor antagonist. Mirogabalin attenuated moving distances 1 and 2 h after oral administration and 10 min after intracerebroventricular administration, but not 10 min after intrathecal administration. In the oral administration group, the time course of the analgesic effect was different from that of moving distance. In the intracerebroventricular group, mirogabalin attenuated moving distances but did not produce an analgesic effect. In the intrathecal group, mirogabalin produced an analgesic effect but did not affect moving distances. These findings suggest that the analgesic effect of mirogabalin on the rat formalin test is mediated by spinal action and not by the activation of α2, 5-HT1A, or opioid receptors, and that the inhibitory effect of mirogabalin on moving distances is mediated by the supraspinal brain.

Guidelines for clinical evaluation of anti-cancer drugs.

Clinical studies intended for regulatory approval must demonstrate the clinical benefits of the drug in a target population. Clinical development of a drug proceeds by stepwise clinical studies; after safety and pharmacokinetics are evaluated and the recommended dosage and administration are determined, efficacy and safety are evaluated in an exploratory manner, and finally clinical benefits are compared with conventional standard therapies. Guidelines for the clinical evaluation of anti-cancer drugs in Japan were established in 1991 and amended in 2006 after molecular-targeted drugs were introduced. Recent progress in the development of drugs acting on the immune system and cancer genomic medicine targeting rare but important molecular subtypes have altered the strategy for development of anti-cancer drugs. It is often difficult to conduct a confirmatory randomized controlled study using overall survival as the primary endpoint in rare molecular subtypes, and the primary evaluation of the efficacy of some drugs and subsequent approval is based on the tumor response. As conducting clinical studies for rare subtypes solely within Japan is difficult, drug development needs to be conducted within a global study. However, this requires robust monitoring to detect possible ethnic differences in pharmacokinetics and drug efficacy. Development using the conditional approval system for drugs enforced in 2020 may be considered, when clinical utility is evaluated based on surrogate endpoints. Because of these changes, we have revised the guidelines for the clinical evaluation of anti-cancer drugs in Japan. To promote global development of anti-cancer drugs involving Japan, the guidelines have been translated into English.

Designation Products: Boron Neutron Capture Therapy for Head and Neck Carcinoma.

The Japanese Ministry of Health, Labour and Welfare approved a drug called borofalan (10 B), a treatment system, and a dose calculation program for boron neutron capture therapy (BNCT) in March 2020. The application pertaining to the products submitted to the Pharmaceuticals and Medical Devices Agency was supported by a Japanese, open-label, uncontrolled trial (Study 002) in patients with unresectable, locally recurrent head and neck squamous cell carcinoma after chemoradiotherapy or radiotherapy, or in those with unresectable locally advanced or locally recurrent (LA/LR) head and neck nonsquamous cell carcinoma. The drug was administered as a single intravenous dose using infusion rates of 200 mg/kg per hour for the first 2 hours after the start of administration and 100 mg/kg per hour during irradiation. Neutron irradiation was performed using the devices at a single dose of 12 Gy-equivalent for oral, pharyngeal, or laryngeal mucosa for up to 60 minutes from 2 hours after the start of drug administration. The primary endpoint was the overall response rate (ORR). The results of Study 002 showed that the ORR based on an assessment of the Independent Central Review Committee per RECIST version 1.1 was 71.4% (90% confidence interval [CI], 51.3%-86.8%). The lower limit of the 90% CI exceeded the prespecified threshold for ORR. When BNCT is applied to patients with unresectable LA/LR head and neck cancer, precautions should be taken, and patients should be monitored for possible onset of dysphagia, brain abscess, skin disorder, crystal urine, cataract, and/or carotid hemorrhage. IMPLICATIONS FOR PRACTICE: Borofalan (10 B), a treatment system and a dose calculation program for boron neutron capture therapy (BNCT), demonstrated significant efficacy in an open-label, uncontrolled trial in which overall response rate was the primary endpoint for patients with unresectable locally advanced or locally recurrent head and neck cancer. Although no information about survival benefits was obtained, BNCT will become an effective treatment option that is expected to manage local lesions that are intractable with any standard therapy. In addition, BNCT is expected to maintain quality of life of the intended patient population, on account of its high tumor selectivity and low invasiveness.