A phase I, randomized, placebo-controlled study of molnupiravir in healthy Japanese to support special approval in Japan to treat COVID-19

Molnupiravir (MK-4482) is an oral prodrug of the antiviral ribonucleoside analog, N-hydroxycytidine (NHC), which has activity against RNA viruses, including severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). We conducted a phase I safety and pharmacokinetic study of molnupiravir in healthy Japanese adult participants. A sample size larger than typically used in pharmacokinetic studies was implemented to collect additional safety data in the Japanese population to support special approval for emergency use in Japan. Single doses of molnupiravir up to 1600 mg and multiple doses of 400 and 800 mg administered every 12 h (q12h) for 5.5 days were generally well-tolerated. NHC appeared rapidly in plasma and reached maximum concentration (C_max ), with a median time to C_max (T_max ) between 1.00 and 2.00 h. Area under the concentration versus time curve from zero to infinity (AUC_0-inf ), area under the concentration versus time curve from zero to 12 h (AUC_0-12 ), and C_max of plasma NHC increased approximately dose proportionally. With q12h dosing, the geometric mean (GM) accumulation ratios for NHC AUC_0-12 and C_max were ~1 for 400 and 800 mg. Pharmacokinetics of NHC triphosphate (NHC-TP), the active metabolite of NHC was assessed in peripheral blood mononuclear cells and also demonstrated roughly dose proportional pharmacokinetics. The GM accumulation ratios for NHC-TP AUC_0-12 and C_max were ~2.5 for 400 and 800 mg. Following administration with food, only a modest reduction (24%) in plasma NHC C_max with comparable AUC_0-inf was seen, supporting administration without regard to food.

Pembrolizumab Plus Chemotherapy in Japanese Patients With Persistent, Recurrent or Metastatic Cervical Cancer: Results From KEYNOTE ‐826

Pembrolizumab plus chemotherapy with or without bevacizumab demonstrated prolonged progression‐free survival (PFS) and overall survival (OS) versus chemotherapy in patients with persistent, recurrent, or metastatic cervical cancer in the phase 3, randomized, double‐blind, placebo‐controlled KEYNOTE‐826 study. We report outcomes in patients enrolled in Japan. Patients received pembrolizumab 200 mg or placebo Q3W for up to 35 cycles plus chemotherapy (paclitaxel 175 mg/m² + cisplatin 50 mg/m² or carboplatin AUC 5) with or without bevacizumab 15 mg/kg. Dual primary endpoints were PFS per RECIST v1.1 by investigator assessment and OS in the global population; these were evaluated in patients with tumors with PD‐L1 combined positive score (CPS) ≥1, all‐comers, and PD‐L1 CPS ≥10. Fifty‐seven patients from Japan were randomized (pembrolizumab plus chemotherapy, n = 35; placebo plus chemotherapy, n = 22). Pembrolizumab plus chemotherapy improved PFS versus placebo plus chemotherapy in patients with PD‐L1 CPS ≥1 (n = 51; hazard ratio [HR; 95% CI], 0.36 [0.16–0.77]), all‐comers (n = 57; 0.45 [0.22–0.90]), and patients with PD‐L1 CPS ≥10 (n = 25; 0.36 [0.12–1.07]). HRs (95% CI) for OS were 0.38 (0.14–1.01), 0.41 (0.17–1.00), and 0.37 (0.10–1.30), respectively. Incidence of grade 3–5 AEs was 94% in the pembrolizumab group and 100% in the placebo group. Consistent with findings in the global KEYNOTE‐826 study, pembrolizumab plus chemotherapy with or without bevacizumab may prolong survival versus placebo plus chemotherapy with or without bevacizumab and had a manageable safety profile in Japanese patients with persistent, recurrent, or metastatic cervical cancer.

Efficacy and safety of nintedanib in Japanese patients with progressive fibrosing interstitial lung diseases: Subgroup analysis of the randomised, double-blind, placebo-controlled, phase 3 INBUILD trial

BACKGROUND

The efficacy of nintedanib in progressive fibrosing interstitial lung diseases (ILDs) was demonstrated in the randomised, double-blind, placebo-controlled INBUILD trial. This subgroup analysis evaluated the efficacy and safety of nintedanib in the Japanese population.

METHODS

Patients with progressive fibrosing ILDs (evaluated by physicians within 24 months of screening) were randomised (1:1) to twice-daily 150-mg nintedanib or placebo; treatment continued until the last patient completed 52 weeks. The primary endpoint was the annual rate of decline in forced vital capacity (FVC) over 52 weeks. Time-to-first acute ILD exacerbation or death and time-to-death up until the last patient had completed the week 52 visit were evaluated. This subgroup analysis included 108 Japanese patients.

RESULTS

The adjusted annual rates of FVC decline (mL/year) over 52 weeks for Japanese patients were -148.31 (nintedanib) and -240.36 (placebo), adjusted difference: 92.05 (95% CI: -10.69-194.80) and for non-Japanese patients were -67.41 (nintedanib) and -177.65 (placebo), adjusted difference: 110.24 (95% CI: 64.97-155.52). No heterogeneity in treatment effect between Japanese and non-Japanese subgroups was observed (treatment-by-subgroup interaction, p = 0.75). The risks of "acute exacerbation or death" (hazard ratio, 0.30 [95% CI: 0.10-0.91]) and mortality (hazard ratio, 0.54 [95% CI: 0.14-2.11]) in Japanese patients were numerically lower for nintedanib than placebo. There were no new or unexpected safety findings.

CONCLUSIONS

In Japanese patients, nintedanib slowed ILD progression, evidenced by a reduction in the annual rate of decline in FVC vs placebo. The efficacy and safety of nintedanib in Japanese patients were consistent with the overall INBUILD population. CLINICALTRIALS.GOV: NCT02999178 (21-Dec-2016).

Nintedanib in patients with systemic sclerosis-associated interstitial lung disease: A Japanese population analysis of the SENSCIS trial

OBJECTIVE

We examined the efficacy and safety of nintedanib in Japanese patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) in the global Safety and Efficacy of Nintedanib in Systemic Sclerosis (SENSCIS) trial.

METHODS

Randomised patients received oral nintedanib 150 mg (N = 34) twice daily or placebo (N = 36) until the last patient reached 52 weeks of treatment (up to 100 weeks). Data were analysed using a subgroup analysis model with Japanese and non-Japanese patients as subgroup variables.

RESULTS

In Japanese patients, the adjusted annual rate of forced vital capacity (FVC) decline over 52 weeks was -86.2 mL/year (nintedanib) and -90.9 mL/year (placebo); treatment difference, 4.67 mL/year (95% confidence interval, -103.28, 112.63). Treatment effect heterogeneity between Japanese and non-Japanese patients was not detected (treatment-by-visit-by-subgroup interaction; p = .49). FVC decline was smaller for nintedanib versus placebo through 100 weeks in Japanese patients. The most commonly reported adverse events with nintedanib were gastrointestinal and liver disorder events; most were mild-to-moderate in severity.

CONCLUSION

In both Japanese and non-Japanese patients with SSc-ILD, nintedanib slowed the progression of ILD, with no heterogeneity detected between the subgroups. The safety profile for nintedanib in Japanese patients was similar to that observed in patients with idiopathic pulmonary fibrosis (ClinicalTrials.gov: NCT02597933).

Restricted mean survival time as a summary measure of time-to-event outcome

Many clinical research studies evaluate a time-to-event outcome, illustrate survival functions, and conventionally report estimated hazard ratios to express the magnitude of the treatment effect when comparing between groups. However, it may not be straightforward to interpret the hazard ratio clinically and statistically when the proportional hazards assumption is invalid. In some recent papers published in clinical journals, the use of restricted mean survival time (RMST) or τ-year mean survival time is discussed as one of the alternative summary measures for the time-to-event outcome. The RMST is defined as the expected value of time to event limited to a specific time point corresponding to the area under the survival curve up to the specific time point. This article summarizes the necessary information to conduct statistical analysis using the RMST, including the definition and statistical properties of the RMST, adjusted analysis methods, sample size calculation, information fraction for the RMST difference, and clinical and statistical meaning and interpretation. Additionally, we discuss how to set the specific time point to define the RMST from two main points of view. We also provide developed SAS codes to determine the sample size required to detect an expected RMST difference with appropriate power and reconstruct individual survival data to estimate an RMST reference value from a reported survival curve.

Open-label phase 2 study of faldaprevir, deleobuvir and ribavirin in Japanese treatment-naive patients with chronic hepatitis C virus genotype 1 infection

AIM

The safety and efficacy of the NS3/4A protease inhibitor faldaprevir in combination with the non-nucleoside NS5B polymerase inhibitor deleobuvir and ribavirin in Japanese treatment-naive patients with chronic genotype 1 hepatitis C virus (HCV) infection was evaluated.

METHODS

In this multicenter, open-label phase 2 study, patients were assigned to 8 weeks of treatment with 80 mg (group 1) or 120 mg (group 2) faldaprevir once daily (q.d.) in combination with deleobuvir 600 mg twice daily and weight-based ribavirin. This was followed by a 24-week treatment with faldaprevir 120 mg q.d. in combination with peginterferon-α-2a and ribavirin. The primary objective was safety; virological response at weeks 4 and 8 was a secondary endpoint.

RESULTS

Twelve and 13 patients were treated in group 1 and 2, respectively; all were infected with HCV genotype 1b. All patients experienced a drug-related adverse event (AE). The frequency of individual events was generally numerically greater in group 2 than 1. The most common AEs were nausea (66.7%, group 1; 76.9%, group 2) and vomiting (33.3%, group 1; 61.5%, group 2). Virological response at weeks 4 and 8 was achieved by 11 (91.7%) patients in group 1; in group 2, 12 (92.3%) patients achieved virological response at week 4 and all at week 8. All patients who achieved the week 8 endpoint achieved sustained virological response at week 12.

CONCLUSION

Faldaprevir 80 or 120 mg q.d. in combination with deleobuvir and ribavirin was tolerable and had similar efficacy in Japanese patients with HCV genotype 1 infection. ClinicalTrials.gov: NCT01528735.

JDP2 suppresses adipocyte differentiation by regulating histone acetylation

Among the events that control cellular differentiation, the acetylation of histones plays a critical role in the regulation of transcription and the modification of chromatin. Jun dimerization protein 2 (JDP2), a member of the AP-1 family, is an inhibitor of such acetylation and contributes to the maintenance of chromatin structure. In an examination of Jdp2 'knock-out' (KO) mice, we observed elevated numbers of white adipocytes and significant accumulation of lipid in the adipose tissue in sections of scapulae. In addition, mouse embryo fibroblasts (MEFs) from Jdp2 KO mice were more susceptible to adipocyte differentiation in response to hormonal induction and members of the CCAAT/enhancer-binding proteins (C/EBP) gene family were expressed at levels higher than MEFs from wild-type mice. Furthermore, JDP2 inhibited both the acetylation of histone H3 in the promoter of the gene for C/EBPdelta and transcription from this promoter. Our data indicate that JDP2 plays a key role as a repressor of adipocyte differentiation by regulating the expression of the gene for C/EBPdelta via inhibition of histone acetylation.

Interaction of Myc-associated zinc finger protein with DCC, the product of a tumor-suppressor gene, during the neural differentiation of P19 EC cells

Expression of the DCC (deleted in colorectal cancer) protein is strongly induced during the neural differentiation of mouse P19 embryonal carcinoma (EC) cells that occurs when these cells are treated with retinoic acid (RA). Myc-associated zinc finger protein (MAZ) is a DNA-binding protein that is widely expressed and functions in human, mouse and hamster cells as an activator, an initiator or a terminator of transcription. However, the biological functions of MAZ remain elusive. We report here that MAZ associates with the cytoplasmic domain of the DCC protein in vivo and in vitro. Yeast two-hybrid assays confirmed this association. An immunofluorescence study demonstrated that DCC protein is expressed at elevated levels in neuron-like P19 EC cells, in particular in axons, in which the MAZ protein is also expressed. We found that MAZ was translocated from the nucleus to the cytoplasm during the RA-induced terminal differentiation of P19 EC cells with resultant loss of the ability of MAZ to bind to the ME1a1 site of the c-myc promoter. Taken together, our observations imply that the DCC protein might play a critical role as a signaling molecule in the regulation of the transcriptional activity of MAZ during the neural differentiation of P19 EC cells.

Two consecutive zinc fingers in Sp1 and in MAZ are essential for interactions with cis-elements

The zinc finger proteins Sp1 and Myc-associated zinc finger protein (MAZ) are transcription factors that control the expression of various genes. Regulation of transcription by these factors is based on interactions between GC-rich DNA-binding sites (GGGCGG for Sp1 and GGGAGGG for MAZ) and the carboxyl-terminal zinc finger motifs of the two proteins. Sp1 and MAZ have three and six zinc fingers, respectively, and the details of their interactions with cis-elements remain to be clarified. We demonstrate here that Sp1 and MAZ interact with the same GC-rich DNA-binding sites, apparently sharing DNA-binding sites with each other. We found that the DNA binding activities of Sp1 and MAZ depended mainly on consecutive zinc fingers, namely the second and third zinc fingers in Sp1 and the third and fourth zinc fingers in MAZ. Furthermore, the interactions of the zinc finger proteins with the same cis-elements appear to play a critical role in the regulation of gene expression. It seems plausible that two consecutive zinc finger motifs in a zinc finger protein might be essential for interaction of the protein with DNA.

Independent repression of a GC-rich housekeeping gene by Sp1 and MAZ involves the same cis-elements

The transcription factors Sp1 and MAZ (Myc-associated zinc finger protein) contain several zinc finger motifs, and each functions as both a positive and a negative regulator of gene expression. In this study, we characterized the extremely GC-rich promoter of the human gene for MAZ, which is known as a housekeeping gene. Unique symmetrical motifs in the promoter region (nucleotides -383 to -334) were essential for the expression of the gene for MAZ, whereas an upstream silencer element (nucleotides -784 to -612) was found to act in a position-dependent but orientation-independent manner. Sp1 and MAZ bound to the same cis-elements in the GC-rich promoter, apparently sharing DNA-binding sites. The relative extent of binding of Sp1 and MAZ to these cis-elements corresponded to the extent of negative regulation of the expression of the gene for MAZ in various lines of cells. Furthermore, novel repressive domains in both Sp1 (amino acids 622-788) and MAZ (amino acids 127-292) were identified. Suppression by Sp1 and suppression by MAZ were independent phenomena; histone deacetylases were involved in the autorepression by MAZ itself, whereas DNA methyltransferase 1 was associated with suppression by Sp1. Our results indicate that both deacetylation and methylation might be involved in the regulation of expression of a single gene via the actions of different zinc finger proteins that bind to the same cis-elements.

Identification of mouse Jun dimerization protein 2 as a novel repressor of ATF-2

A mouse cDNA that encodes a DNA-binding protein was identified by yeast two-hybrid screening, using activating transcription factor-2 (ATF-2) as the bait. The protein contained a bZIP (basic amino acid-leucine zipper region) domain and its amino acid sequence was almost identical to that of rat Jun dimerization protein 2 (JDP2). Mouse JDP2 interacted with ATF-2 both in vitro and in vivo via its bZIP domain. It was encoded by a single gene and various transcripts were expressed in all tested tissues of adult mice, as well as in embryos, albeit at different levels in various tissues. Furthermore, mouse JDP2 bound to the cAMP-response element (CRE) as a homodimer or as a heterodimer with ATF-2, and repressed CRE-dependent transcription that was mediated by ATF-2. JDP2 was identified as a novel repressor protein that affects ATF-2-mediated transcription.

TOK-1, a novel p21Cip1-binding protein that cooperatively enhances p21-dependent inhibitory activity toward CDK2 kinase

A p21(Cip1/Waf1/Sdi1) is known to act as a negative cell-cycle regulator by inhibiting kinase activity of a variety of cyclin-dependent kinases. In addition to binding of the cyclin-dependent kinase to the N-terminal region of p21, p21 is also bound at its C-terminal region by proliferating cell nuclear antigen (PCNA), SET/TAF1, and calmodulin, indicating the versatile function of p21. In this study, we cloned cDNA encoding a novel protein named TOK-1 as a p21 C-terminal-binding protein by a two-hybrid system. Two splicing isoforms of TOK-1, TOK-1alpha and TOK-1beta, comprising 322 and 314 amino acids, respectively, were co-localized with p21 in nuclei and showed a similar expression profile to that of p21 in human tissues. TOK-1alpha, but not TOK-1beta, directly bound to the C-terminal proximal region of p21, and both were expressed at the G(1)/S boundary of the cell cycle. TOK-1alpha also preferentially bound to an active form of cyclin-dependent kinase 2 (CDK2) via p21, and these made a ternary complex in human cells. Furthermore, the results of three different types of experiments showed that TOK-1alpha enhanced the inhibitory activity of p21 toward histone H1 kinase activity of CDK2. TOK-1alpha is thus thought to be a new type of CDK2 modulator.

The coactivators p300 and CBP have different functions during the differentiation of F9 cells

We have characterized an element (differentiation response element, DRE) in the promoter region of the c-jun gene that is both necessary and sufficient for retinoic acid (RA) and adenovirus early region (E1A) mediated up-regulation of c-jun gene expression during the differentiation of F9 cells. The DRF complex, which binds specifically to DRE, is composed of the E1A-associated protein p300 and the activation transcription factor-2 (ATF-2) as a DNA-binding subunit of the DRF. The molecular association of p300 and ATF-2 enhances the transcription of the c-jun gene, which requires protein kinase C alpha mediated phosphorylation of Ser-121 of ATF-2 within its p300 interaction domain. We used antisense oligodeoxynucleotides (AS-ODNs) capable of binding specifically to the mRNA for either p300 or CBP to examine the individual roles of p300 and CBP during the RA-induced differentiation, exit from the cell cycle, and apoptosis of F9 cells. F9 cells treated with AS-ODNs specific for p300 mRNA became resistant to RA-induced differentiation, while cells incubated with AS-ODNs specific for CBP mRNA were still able to differentiate. Despite their similarities p300 and CBP appear to have distinct functions during the differentiation of F9 cells. These results suggest that ATF-2 and p300 cooperate in the control of transcription by forming a protein complex in response to RA or E1A, and that the phosphorylation of ATF-2 and p300 is probably a signaling event in the pathway that leads to the transactivation of the c-jun gene in F9 cell differentiation.

Structural organization and expression of the mouse gene for Pur-1, a highly conserved homolog of the human MAZ gene

We have characterized the genomic structure and expression of the mouse gene for Pur-1. The cloned Pur-1 gene spans a 5-kb region encompassing the promoter, five exons, four introns and the 3'-untranslated region. All exon-intron junction sequences conform to the GT/AG rule. The promoter region has typical features of a housekeeping gene: a high G + C content (77.5%); a high frequency of CpG dinucleotides, in particular within the region 0.5 kb upstream of the site of initiation of translation; and the absence of canonical TATA and CAAT boxes. S1 nuclease protection assay demonstrated the presence of multiple sites for initiation of transcription around a site 108 nucleotides upstream of the ATG codon. Comparison of Pur-1 with the human gene for MAZ (Myc-associated zinc finger protein) revealed a striking homology of both their nucleotide and deduced protein sequences, an identical genomic organization and high similarity in promoter architecture and mRNA expression pattern. Sequence analysis of the 5'-flanking region of Pur-1 revealed numerous potential binding sites for transcription factors Sp1, AP-2 and Pur-1/MAZ itself. An element required for basal Pur-1 expression was mapped from nucleotide -258 to +43. This region also mediated stimulation of basal transcription by ectopically expressed MAZ protein. We conclude that the Pur-1 gene is the murine homolog of human MAZ and, like it, belongs to the family of housekeeping genes.

p300 and ATF-2 are components of the DRF complex, which regulates retinoic acid- and E1A-mediated transcription of the c-jun gene in F9 cells

Transcriptional activation of the c-jun gene is a critical event in the differentiation of F9 cells. In our previous studies we characterized an element [differentiation response element (DRE)] in the c-jun promoter that is both necessary and sufficient to confer the capacity for differentiation-dependent up-regulation. This element binds the differentiation regulatory factor (DRF) complex, of which one component is the adenovirus E1A-associated protein p300. We have now identified activation transcription factor-2 (ATF-2) as a DNA-binding subunit of the DRF complex. p300 and ATF-2 interact with each other in vivo and in vitro. The bromodomain and the C/H2 domain of p300 mediate the binding to ATF-2, which in turn requires a proline-rich region between amino acids 112 and 350 for its interaction with p300. The phosphorylation of the serine residue at position 121 of ATF-2 appears to be induced by protein kinase C alpha (PKC alpha) after treatment of cells with retinoic acid (RA) or induction with E1A. In cotransfection assays, wild-type ATF-2 enhanced the transcription of an E2/tk-luciferase construct, in conjunction with p300-E2. However, a mutant form of ATF-2 with a mutation at position 121 (pCMVATF-2(Ser121-Ala)) did not. These results suggest that ATF-2 and p300 cooperate in the control of transcription by forming a protein complex that is responsive to differentiation-inducing signals, such as RA or E1A, and moreover, that the phosphorylation of ATF-2 by PKC alpha is probably a signaling event in the pathway that leads to the transactivation of the c-jun gene in F9 cells.

Assignment of the human gene for KBF2/RBP-Jk to chromosome 9p12-13 and 9q13 by fluorescence in situ hybridization

The transcription factor KBF2 has been characterized as a factor that binds to the NFkB site of mouse major histocompatibility complex (MHC) class I genes and its amino acid sequence has been shwn to be identical to those of members of the recombination signal-sequence binding protein (RBP-Jk) family. Previous studies by Amakawa et al. (Genomics 17, 306-315, 1993) demonstrated that the functional gene is localized at human chromosome 3q25. However, in the present study we showed by in situ hybridization with the functional KBF2/RBPJk cosmid clone that the gene is localized at 9p12-13 and 9q13, namely, at the same loci as pseudogenes that were reported previously (Zhang et al, Jpn J Human Genet 39, 391-401, 1994).

Detection of Bacteroides fragilis by PCR assay targeting the neuraminidase-encoding gene

Oligonucleotide primers were designed on the basis of the sequence of the neuraminidase-encoding gene (nanH) of Bacteroides fragilis and used for the specific detection of this anaerobe by the nested PCR assay. Fifty-nine of 60 representative strains of Bact. fragilis were detected, while none of 45 strains of other species generated visible PCR products. The detection limits of Bact. fragilis cells and DNA by the nested PCR were 10 colony-forming units and 10 fg of chromosomal DNA, respectively. The PCR assay targeting the nanH gene has the potential for the detection of Bact. fragilis.

Nucleotide sequence of the gene encoding beta-isopropylmalate dehydrogenase (leuB) from Bacteroides fragilis

The complete nucleotide sequence of the gene (leuB) coding for beta-isopropylmalate dehydrogenase of Bacteroides fragilis was determined. An open reading frame of 1,061 nucleotides was detected that could encode a polypeptide of 353 amino acid residues with a calculated molecular mass of 39,179 Da. The deduced amino acid sequence of the beta-isopropylmalate dehydrogenase from B. fragilis showed substantial sequence similarity with the beta-isopropylmalate dehydrogenases from other bacteria.

[A case of ischemic colitis due to polyarteritis nodosa]

A 78-year-old female was admitted to our hospital with acute abdomen (abdominal pain and bloody stool). Abdominal examination revealed mild rebound tenderness on the right side. The laboratory data revealed severe inflammation (WBC: 33100/microliters, CRP:35.5 mg/dl). Panperitonitis was suspected because of diffuse and severe abdominal pain and rebound tenderness on the next day. X-ray examination by gastrografin showed mucosal irregularity and tubular narrowing of the tubular narrowing of the ascending colon which indicated ischemic colitis, and an emergency operation was performed. Histological examination of the pathologic specimens revealed fibrinoid necrosis and destruction of the internal lamina in small and medium-size arteries. We report a case diagnosed as ischemic colitis due to polyarteritis nodosa by the findings of its pathologic specimens.