Advanced Methods for Dose and Regimen Finding During Drug Development: Summary of the EMA/EFPIA Workshop on Dose Finding (London 4-5 December 2014).

Inadequate dose selection for confirmatory trials is currently still one of the most challenging issues in drug development, as illustrated by high rates of late-stage attritions in clinical development and postmarketing commitments required by regulatory institutions. In an effort to shift the current paradigm in dose and regimen selection and highlight the availability and usefulness of well-established and regulatory-acceptable methods, the European Medicines Agency (EMA) in collaboration with the European Federation of Pharmaceutical Industries Association (EFPIA) hosted a multistakeholder workshop on dose finding (London 4-5 December 2014). Some methodologies that could constitute a toolkit for drug developers and regulators were presented. These methods are described in the present report: they include five advanced methods for data analysis (empirical regression models, pharmacometrics models, quantitative systems pharmacology models, MCP-Mod, and model averaging) and three methods for study design optimization (Fisher information matrix (FIM)-based methods, clinical trial simulations, and adaptive studies). Pairwise comparisons were also discussed during the workshop; however, mostly for historical reasons. This paper discusses the added value and limitations of these methods as well as challenges for their implementation. Some applications in different therapeutic areas are also summarized, in line with the discussions at the workshop. There was agreement at the workshop on the fact that selection of dose for phase III is an estimation problem and should not be addressed via hypothesis testing. Dose selection for phase III trials should be informed by well-designed dose-finding studies; however, the specific choice of method(s) will depend on several aspects and it is not possible to recommend a generalized decision tree. There are many valuable methods available, the methods are not mutually exclusive, and they should be used in conjunction to ensure a scientifically rigorous understanding of the dosing rationale.

The Role of Modeling and Simulation in Development and Registration of Medicinal Products: Output From the EFPIA/EMA Modeling and Simulation Workshop.

The European Medicines Agency (EMA) and the Federation of Pharmaceutical Industries and Associations (EFPIA) hosted a workshop on modeling and simulation (M&S).(1) Representatives from industry, academia, and regulatory agencies from Europe and beyond discussed the role of M&S in the development and registration of medicinal products within plenary and breakout sessions (BOS). This manuscript summarizes the plenary discussion (Table 1) focusing on the European perspective. Deliverables from each BOS are included in separate papers.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e31; doi:10.1038/psp.2013.7; advance online publication 27 February 2013.

Fatal massive hemolysis as the first manifestation of Clostridium perfringens septicemia in a patient with non-systematic or local predisposing disorder.

We report a case of fulminant massive hemolysis due to Clostridium perfringens septicemia in an elderly patient with non-systematic or local predisposing disorder. The patient presented with atypical symptoms but the progress of the disease was extremely rapid and he died almost 3h after his hospital admission. A focal infection or a possible portal of bacterial access was not found.

Low genetic diversity of the intrinsic OXA-51-like class D carbapenemases among Acinetobacter baumannii clinical isolates in Greece.

This study examined the geographical distribution and diversity of the intrinsic OXA-51-like class D carbapenemases among Acinetobacter baumannii clones recovered in three major Greek regions from 2000 to 2005. The blaOXA-66 allele was exclusively detected among clonally distinct A. baumannii isolates recovered in the regions of Thessaloniki and Larissa. This sequence was also the most widespread among A. baumannii isolates in Athens, while less frequent were blaOXA-69 and blaOXA-65 alleles. These findings highlight the high prevalence of a specific blaOXA-51-like allele in Greece, possibly indicating that our A. baumannii clones might have originated from a common ancestor. However, the possibility that blaOXA-51-like variants, with blaOXA-66 predominating, are widely disseminated among several unrelated A. baumannii strains cannot be excluded.

The influence of local instillation of fusidic acid on the development of microbial complications after lung resection.

The efficacy of local instillation of fusidic acid in the prevention of post-surgical microbial complications during various types of lung resection was studied. Four hundred ninety two consecutive patients who underwent 504 thoracotomies for non-small cell lung carcinoma during April 1998-May 2004 were reviewed. The 290 patients of the first period who underwent 298 thoracotomies received a chemoprophylactic regimen of intravenous cefuroxime while the 202 patients of the second period who underwent 206 thoracotomies were additionally treated with fusidic acid, irrigated with local instillation into the pleural space, for the prevention of postoperative septic complications. Patients were followed postoperatively for development of septic complications (empyema and bronchopleural fistula) as well as of pneumonia and wound infection. Seventeen patients (5.7%) of the first period developed empyema and 13 fistula (4.4%), whereas only 2 patients (1.0%) of the second period developed empyema and fistula (OR = 5.876; 95% CI, 1.343- 25.716; P = 0.008 and OR = 4.193; 95% CI, 1.003-20.130; P = 0.034, respectively). Cases of pneumonia decreased, but not significantly, from 21 (7.0%) during the first period to 9 (4.4%) during the second period (OR = 1.613; 95% CI, 0.724-3.593; P = 0.257) while cases of wound infection decreased significantly from 19 (6.4%) to 2 (1.0%) (OR = 6.567; 95% CI, 1.513-28.510; P = 0.003). During the first period 23 pathogens were found from cases of empyema and 73 pathogens from cases of pneumonia and wound infection, whereas during the second period 3 and 18 pathogens were respectively found (OR = 5.3; 95% CI, 1.570-17.888; P = 0.003, and OR = 2.804; 95% CI, 1.628-4.838; P <0.001, respectively). These results indicate that local instillation of fusidic acid in the pleural space prior to lung resection seems effective in reducing the rate of septic complications as well as of wound infections.

Coxsackievirus B3 sequences in the myocardium of fatal cases in a cluster of acute myocarditis in Greece.

AIM: The investigation of three fatal cases during a nationwide cluster of cases of an upper respiratory tract infection (URTI) associated with myocarditis and/or pericarditis in Greece in 2002. METHODS: In the three women who died, necropsies were performed and tissue sections were taken for histological examination, antigen detection by immunohistochemistry and indirect immunofluorescence assay (IFA), amplification of viral genomes by nested reverse transcription polymerase chain reaction (RT-PCR), and sequence analysis. RESULTS: All samples showed histological signs of active myocarditis. Immunohistochemistry revealed the presence of the enterovirus VP1 family of proteins and IFA revealed the presence of coxsackievirus B3 antigen. Nested RT-PCR amplified enteroviral alleles of the 5'-untranslated region which were identical to each other and to the coxsackievirus B3 sequences. CONCLUSIONS: This study provides pathological evidence of enteroviral infection among fatal myocarditis cases in a nationwide URTI cluster of cases associated with myocarditis and/or pericarditis.

Transcriptional impairment of beta-catenin/E-cadherin complex is not associated with beta-catenin mutations in colorectal carcinomas.

We report the absence of beta-catenin mutations in 63 sporadic colorectal carcinomas (SCRCs) with demonstrated decreased beta-catenin and E-cadherin mRNA expression and E-cadherin protein expression in a subset of carcinomas examined, suggesting that beta-catenin mutations are an extremely rare phenomenon in SCRCs and are not responsible for the transcriptional impairment of the beta-catenin/E-cadherin adhesion complex observed in these tumours.

c-mos immunoreactivity is an indicator of good prognosis in lung cancer.

AIMS: Reports concerning the expression of cytoplasmic components of the mitogen-activating protein kinase (MAPK) pathway in lung cancer are limited. One of the molecules participating in this pathway is the product of the c-mos proto-oncogene. In vitro investigations, in somatic cells, have shown that c-mos expression has opposing effects on cell cycle progression suggesting that it may represent an important determinant of aberrant cell function. In this study we analysed, by immunohistochemical means, its status in a series of lung carcinomas and correlated the findings with clinicopathological parameters and survival of the patients. METHODS AND RESULTS: Sixty cases of lung carcinomas were included in the study. These comprised 52 non-small (NSCLCs) and eight small cell lung carcinomas (SCLCs). Sections from the carcinomas were immunostained with the polyclonal anti-c-mos antibody P-19. Specificity was tested by using the appropriate control peptide and control cell lines. Expression was observed in 63% of the cases, with NSCLCs showing higher reactivity (67%) than SCLCs (37.5%). Staining was observed mainly to the cytoplasm and membranes of the cancerous cells, but some nuclei reacted as well. An intratumour heterogeneous immunoreactivity was noticed. The most interesting and unexpected finding was that c-mos positive staining was associated with better recurrence-free survival in our series, regardless of histological type (P = 0.035). Furthermore, favourable disease-related and recurrence-free survival was observed in the SqC group with c-mos immunoreactivity (P < 0. 001). CONCLUSIONS: c-mos proto-oncogene is expressed in a significant proportion of lung carcinomas and may play a role in its development. The fact that its expression is associated with a relatively good prognosis may be indicative of a negative impact on tumour growth.

Allelic imbalance at the 5q14 locus is associated with decreased apoptotic rate in non-small cell lung carcinomas (NSCLCs). Possible synergistic effect with p53 gene alterations on apoptosis.

Deletions in the 5q14 region have been described in a variety of neoplasms, such as testicular germ cell tumors, ovarian, gastric and lung cancer. The high frequency of allelic losses observed in this region implies the presence of putative tumor suppressor gene(s) (TSGs). In the present study, we investigated in a series of 56 non-small cell lung carcinomas (NSCLCs) the allelic imbalance (Alm) within the 5q14 region, employing the D5S644 marker, and its relationship with p53 abnormalities, the kinetic parameters [proliferation index (PI) and apoptotic index (AI)] and the ploidy status of the carcinomas. AI at D5S644 was found at a frequency of 51.2%. The rather high percentage of Alm in stage I tumors suggests an early involvement in NSCLC development. LOH at 5q14 was associated with decreased AR in lung tumors insinuating the presence of a putative TSG(s) (P=0.008). Simultaneous alterations of both p53 and D5S644 locus were the most frequent pattern observed (37.5%). Cases demonstrating this profile also exhibited a marked decrease in AI (P=0.001). These findings imply a synergistic mechanism of co-operation between different TSGs. However, proliferation activity was dependent only on p53 status, leading to the assumption that the putative TSG(s) present at 5q14 may probably be involved in normal apoptotic procedures. Further studies are needed to identify the candidate gene(s).

Expression of p16(INK4A) and alterations of the 9p21-23 chromosome region in non-small-cell lung carcinomas: relationship with tumor growth parameters and ploidy status.

The 9p21-23 chromosome region harbors a number of known and putative tumor-suppressor genes (TSGs). The best characterized gene in this area is p16(INK4A) (CDKN2A). Alterations of its product have been observed in various malignancies, including non-small-cell lung carcinomas (NSCLCs). We earlier investigated the mechanisms underlying p16(INK4A) inactivation. In the present study, we examined, in a series of 87 NSCLCs, its relationship with the kinetic parameters [proliferation index (PI) and apoptotic index (Al)] and the ploidy status of the tumors. In addition, we extended our previous LOH analysis of the 9p21-23 region by examining flanking areas of p16(INK4A). Aberrant p16 expression was observed in 41.4% of the carcinomas. A significant association was found with increased PI (p = 0.037), but not with apoptosis. Aneuploid tumors were more frequently correlated with abnormal p16 staining (p = 0. 05). A high frequency of allelic imbalance (Alm) was noticed at the D9S161 (51.3%) and D9S157 (64.5%) loci, which lie approximately 4cM centromeric and 7cM telomeric, respectively, to CDKN2A. Abnormal p16(INK4A) expression was strongly correlated with Alm at D9S161 (p = 0.004). Allelic losses at D9S157 occurred more frequently in early stages (p = 0.018) and were significantly associated with deletions at D9S161 (p = 0.035). We conclude that, in a sub-set of NSCLCs, (i) abnormal p16 expression contributes to tumor growth mainly by increasing the proliferative activity in the initial stages of carcinogenesis; (ii) the association with aneuploidy merely reflects the impact of aberrant p16 on proliferative activity; and (iii) other putative TSGs possibly reside within the 9p21-23 region that possibly co-operate in certain cases with CDKN2A in the development of NSCLCs.

Sensitive differential detection of genetically related mycobacterial pathogens in archival material.

A polymerase chain reaction (PCR) assay targeted to the immunogenic protein MPB64 gene was used to detect members of the Mycobacterium tuberculosis complex, and an outward-primed PCR (OPPCR) designed on the IS6110 element allowed differentiation between Mycobacterium bovis and Mycobacterium tuberculosis. Additionally, the amplification of IS1110 and 16S ribosomal RNA sequences combined with a dot blotting assay were able to differentially detect Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium paratuberculosis. The validity of the experimental procedure was tested on reference material and formalin-fixed paraffin-embedded samples from patients with tuberculosis, sarcoidosis, or Crohn disease. We demonstrated mycobacterial DNA in 59 of 75 cases with histologic lesions typical of tuberculosis; we detected M tuberculosis and M paratuberculosis in 6 of 25 sarcoidosis cases and in 7 of 20 Crohn disease specimens, respectively. The proposed diagnostic procedure is directly applicable to archival material and allows differentiation of genetically related mycobacterial pathogens in more detail than other molecular methods. It provides a tool for the diagnostic study of tuberculosis, sarcoidosis, and Crohn disease.

Hereditary postlingual sensorineural hearing loss mapping to chromosome Xq21.

BACKGROUND: Mutations on the X-chromosome clinically manifesting different phenotypes of hearing loss have been mapped to the long arm at different loci, DFN1-DFN3. Another defect in a family with sex-linked, postlingual, progressive sensorineural hearing loss was mapped to Xq. METHODS: Clinically, the family was evaluated by physical and audiometric examination of 17 members including computerized tomographic (CT) evaluation of the proband. Molecular evaluation consisted of polymerase chain reaction amplification of patient genomic DNA and resolution 32P-labeled fragments by polyacrylamide gels. Inheritance of DNA alleles and deafness were analyzed using the MLINK computer program. RESULTS: Five affected males demonstrated symmetrical sensorineural hearing loss as significant as 100 decibels (dB). Two carrier females had a milder loss with frequency findings of 10 dB to 60 dB. Computerized tomography (CT) evaluation of the temporal bones of the proband was normal. The odds were 200:1 that the responsible gene was linked to locus DXS986 (maximum lod score = 2.3 at 0 = 0). Analysis of recombination events defined by family members demonstrates that the responsible gene lies in a 21 cM (30 MB) interval, between loci DXS12175 and 1106. The disease locus in this family does not appear to map to DFN1 or DFN3. CONCLUSION: The family described here, with affected males who have progressive, postlingual sensorineural hearing loss and mildly affected females maps most compatibly to the DFN2 locus. Analysis of hereditary deafness in this family refines the DFN2 locus to a 9.2 Mb region in chromosome X band q21 between DXS990 and DXS106.

Recent advances in early prostatic cancer.

Early prostatic carcinoma is a slowly progressing, localized malignant tumor which has been recently discovered with increased frequency due to the use of improved diagnostic methods. The combination of digital rectal examination, serum PSA level and transrectal ultrasound is currently the best available diagnostic tool, although other putative diagnostic markers and techniques are being investigated. Core needle biopsy may follow if there is suspicion of malignancy and in doubtful cases the most useful antibody for the immunohistochemical diagnosis of early, low grade prostatic carcinoma is clone 34 beta E12. Cytogenetic techniques and molecular biological methods are increasingly being used for further investigating localized prostate carcinomas in order to identify early molecular targets and alterations, which may lead to progression. Chromosome abnormalities, cell to cell and cell to matrix interactions, changes in the status of steroid hormone receptors, oncogenes and tumor suppressor genes, as well as other, as yet unclear, events may be of importance in prostate carcinogenesis and the progression of early malignant tumors to aggressive phenotypes. A variety of putative prognostic markers, apart from serum PSA levels, histological grade and tumor volume, such as neuroendocrine differentiation, angiogenesis, cell proliferation labeling index and ploidy analysis may prove useful in evaluating tumor progression in early prostatic carcinomas. The final and most important goal of all investigations related to early prostate cancer is to contribute to the best therapeutic management of the individual patient.

Aberrant p16 expression is correlated with hemizygous deletions at the 9p21-22 chromosome region in non-small cell lung carcinomas.

The p16 protein is encoded by the CDKN2 gene, and functions as an inhibitor of cyclin-dependent kinase 4 and 6 (CDK4/6). Phosphorylation of the retinoblastoma protein (pRb) by CDK4/6 represents a vital step in cell cycle progression. Alterations of p16INK4A are frequent events in human malignancies. In non-small cell lung carcinoma (NSCLC) the data concerning the mechanisms of p16INK4A inactivation suggest that point mutations and aberrant methylation of its promoter can only account for a proportion of the cases with abnormal p16 immunoexpression. The role of deletions in this procedure is not yet clarified. In order to gain more insight into the role of deletions in p16INK4A deregulated expression, we investigated the state of the chromosomal region 9p21-22 in a series of 57 NSCLCs, by performing a detailed mapping analysis, using a tight cluster of highly polymorphic microsatellite markers, and correlating the findings with p16 immunostaining. Abnormal p16 expression was observed in 46% of the NSCLCs examined. No relationship was observed between p16 abnormal staining and various clinicopathological parameters. Abnormal p16 protein staining was strongly associated with hemizygous deletions at the IFNA and D9S171 microsatellite loci, which demarcate the region encoding the p16INK4A gene (P = 0.002). These findings suggest that deregulated expression of p16 is involved in the multistage process of NSCL carcinogenesis and that deletions may represent a predominant mechanism of p16INK4A inactivation. A significant percentage also of LOH was noticed at the D9S162 (35%) and D9S126 (38%) loci which lie 6cM and 4cM, respectively, far from the area which encodes p16INK4A, implying that other tumor suppressor genes (TSGs) may reside in this region. Although the overall incidence of LOH at the examined region was high (58%), we did not observe any correlation with smoking habits, histology and lymph node status. Another noteworthy finding was the existence of microsatellite instability (MI) in 11% of the patients. MI provides a marker for replication error phenotype (RER+), a recently defined manifestation of genetic instability observed in a wide range of tumors. In conclusion, alterations (LOH + MI) at the 9p21-22 chromosome region are frequent events in NSCLCs and may affect directly or indirectly the expression of p16.

Multiplex polymerase chain reaction for the detection of mycobacterial DNA in cases of tuberculosis and sarcoidosis.

The aims of the present study were: (1) to design a sensitive and specific polymerase chain reaction-based method that would allow detection of most common human typical and atypical mycobacterial strains and (2) to apply the method on formalin-fixed paraffin-embedded (FFPE) tissue and sputum samples from patients with clinicopathological evidence of tuberculosis and sarcoidosis. Three sets of primers were selected. The first detects specifically members of the Mycobacterium tuberculosis (M. tuberculosis) complex, amplifying a 243 bp fragment of the gene encoding the immunogenic protein MPB 64, whereas the second traces members of the Mycobacterium avium (M. avium) complex producing a 91 bp fragment of the IS1110 element. The third pair of primers is specific for slow-growing mycobacteria, amplifying a 383 bp region of the 65 kDa mycobacterial antigen gene. Our multiplex polymerase chain reaction assay identified mycobacterial DNA of 10(-3) colony-forming units (CFU)/mL from sputum samples, 10(-5) CFU/mL from FFPE tissue samples and 10(-6) CFU/mL from pure broth cultures. By performing the method on 75 FFPE tissue samples with histological and clinical evidence of tuberculosis and 300 sputum specimens from patients suspected of tuberculosis, we found 38 M. tuberculosis complex, 7 M. avium complex, and 14 slow-growing mycobacteria positive samples in the first case and in the second we found 95 M. tuberculosis complex, 21 M. avium complex, and 35 slow-growing mycobacteria positive samples. The sensitivity of the assay was significantly higher than that of Ziehl-Neelsen and in some cases higher than culture, especially when applied on atypical mycobacteria. In addition, 25 cases histologically and clinically characterized as sarcoidosis were investigated for mycobacterial DNA sequences and in nine of these, DNA corresponding to M. tuberculosis complex was detected. The method described can be applied directly on FFPE and sputum samples and allows not only the detection of mycobacterial DNA, but also an assessment concerning the species involved.

Comparison of the enzyme-linked immunosorbant assay III, recombinant immunoblot third generation assay, and polymerase chain reaction method in the detection of hepatitis C virus infection in haemodialysis patients.

Hepatitis C virus (HCV) serotyping assays have evolved from simple antibody screening tests to complex RNA-based qualitative and quantitative methods. The objective of this study was to compare the HCV screening results from 161 patients in long-term maintenance haemodialysis (HD) as assessed by the recently developed Enzyme Linked ImmunosorbantAssay III (ELISA III), confirmed by the Recombinant Immunoblot 3rd generation assay (RIBA 3rd) and determined by the qualitative HCV reverse transcription polymerase chain reaction (RT-PCR) method. One hundred sixty-one HD patients were tested for the presence of anti-HCV antibodies by the ELISA III and confirmed by the RIBA 3rd. HCV RNA was determined by an HCV RT-PCR method. All reported results that were designated as discrepant, anti-HCV (+) and/or HCV RNA (+) were further investigated by means of a quantitative HCV RT-PCR assay. Reported results obtained from ELISA III and qualitative RT-PCR assays were HCV positive for 16/161 patients (9,93%) and these were designated as anti-HCV (+)/HCV RNA (+). Subsequently, these 16 anti-HCV positive/161 HD patients were confirmed by the RIBA 3rd. Three individuals anti-HCV (-)/RIBA (+)/HCV RNA (-)], the viral load that was reported from the quantitative RT-PCR was less than the assay detection level (< 2,000 viral copies/ml). In view of previous observations, our findings suggest that ELISA III remains still a highly reliable and valuable assay. However, despite the cost, the combination of both ELISA III and qualitative RT-PCR allows a definitive classification on HCV diagnosis.

Modulation of wild-type p53 activity by mutant p53 R273H depends on the p53 responsive element (p53RE). A comparative study between the p53REs of the MDM2, WAFI/Cip1 and Bax genes in the lung cancer environment. WAFI/Cip1 = WAF1/Cip1.

Wild-type (wt) p53 is a tumor-suppressor protein which acts via transcriptional and transcriptional-independent mechanisms. The transcriptional function of p53 is mediated by specific responsive elements (REs). The MDM2, WAF1/Cip1 and Bax genes possess p53REs and their activation by wt p53 induces cell cycle progression, arrest and programmed cell death (apoptosis), respectively. Mutations of the p53 gene are detected in more than 50% of the human malignant tumors. p53 mutants seem to have a more stable conformation and are suggested to exert dominant-negative inhibition of wt p53 in cells containing both wt and mutant (mt) alleles. However, recent studies show that certain mt p53 proteins posses a "gain of function" phenotype. In the present study, we examined the effects of the second most frequent p53 mutant R273H on the p53REs of the MDM2, WAF1/Cip1 and Bax genes in the H1299 non-small cell lung carcinoma cell line. Although mt p53 R273H alone was unable to bind and transactivate the corresponding p53REs, it enhanced the MDM2-p53RE mediated gene transcription of wt p53 (positive-dominant effect) and prevented the wt p53 transactivation of the p53REs of WAF1/Cip1 and Bax genes (negative-dominant effect). Our data suggest that in the appropriate environment, differential transcription of critical p53 target genes by certain p53 mutant proteins may illustrate another mechanism implicated in tumor development.