Oxycodone: A Current Perspective on Its Pharmacology, Abuse, and Pharmacotherapeutic Developments.

Oxycodone, a semisynthetic derivative of naturally occurring thebaine, an opioid alkaloid, has been available for more than 100 years. Although thebaine cannot be used therapeutically due to the occurrence of convulsions at higher doses, it has been converted to a number of other widely used compounds that include naloxone, naltrexone, buprenorphine, and oxycodone. Despite the early identification of oxycodone, it was not until the 1990s that clinical studies began to explore its analgesic efficacy. These studies were followed by the pursuit of several preclinical studies to examine the analgesic effects and abuse liability of oxycodone in laboratory animals and the subjective effects in human volunteers. For a number of years oxycodone was at the forefront of the opioid crisis, playing a significant role in contributing to opioid misuse and abuse, with suggestions that it led to transitioning to other opioids. Several concerns were expressed as early as the 1940s that oxycodone had significant abuse potential similar to heroin and morphine. Both animal and human abuse liability studies have confirmed, and in some cases amplified, these early warnings. Despite sharing a similar structure with morphine and pharmacological actions also mediated by the µ-opioid receptor, there are several differences in the pharmacology and neurobiology of oxycodone. The data that have emerged from the many efforts to analyze the pharmacological and molecular mechanism of oxycodone have generated considerable insight into its many actions, reviewed here, which, in turn, have provided new information on opioid receptor pharmacology. SIGNIFICANCE STATEMENT: Oxycodone, a µ-opioid receptor agonist, was synthesized in 1916 and introduced into clinical use in Germany in 1917. It has been studied extensively as a therapeutic analgesic for acute and chronic neuropathic pain as an alternative to morphine. Oxycodone emerged as a drug with widespread abuse. This article brings together an integrated, detailed review of the pharmacology of oxycodone, preclinical and clinical studies of pain and abuse, and recent advances to identify potential opioid analgesics without abuse liability.

HPV-induced host epigenetic reprogramming is lost upon progression to high-grade cervical intraepithelial neoplasia.

The impact of a pathogen on host disease can only be studied in samples covering the entire spectrum of pathogenesis. Persistent oncogenic human papilloma virus (HPV) infection is the most common cause for cervical cancer. Here, we investigate HPV-induced host epigenome-wide changes prior to development of cytological abnormalities. Using cervical sample methylation array data from disease-free women with or without an oncogenic HPV infection, we develop the WID (Women's cancer risk identification)-HPV, a signature reflective of changes in the healthy host epigenome related to high-risk HPV strains (AUC = 0.78, 95% CI: 0.72-0.85, in nondiseased women). Looking at HPV-associated changes across disease development, HPV-infected women with minor cytological alterations (cervical intraepithelial neoplasia grade 1/2, CIN1/2), but surprisingly not those with precancerous changes or invasive cervical cancer (CIN3+), show an increased WID-HPV index, indicating the WID-HPV may reflect a successful viral clearance response absent in progression to cancer. Further investigation revealed the WID-HPV is positively associated with apoptosis (ρ = 0.48; P < .001) and negatively associated with epigenetic replicative age (ρ = -0.43; P < .001). Taken together, our data suggest the WID-HPV captures a clearance response associated with apoptosis of HPV-infected cells. This response may be dampened or lost with increased underlying replicative age of infected cells, resulting in progression to cancer.

The WID-EC test for the detection and risk prediction of endometrial cancer.

The incidence of endometrial cancer is rising. Measures to identify women at risk and to detect endometrial cancer earlier are required to reduce the morbidity triggered by the aggressive treatment required for advanced endometrial cancer. We developed the WID-EC (Women's cancer risk IDentification-Endometrial Cancer) test, which is based on DNA methylation at 500 CpG sites, in a discovery set of cervical liquid-based cytology samples from 1086 women with and without an endometrial cancer (217 cancer cases and 869 healthy controls) with a worse prognosis (grade 3 or ≥stage IB). We validated the WID-EC test in an independent external validation set of 64 endometrial cancer cases and 225 controls. We further validated the test in 150 healthy women (prospective set) who provided a cervical sample as part of the routine Swedish cervical screening programme, 54 of whom developed endometrial cancer within 3 years of sample collection. The WID-EC test identified women with endometrial cancer with a receiver operator characteristic area under the curve (AUC) of 0.92 (95% CI: 0.88-0.97) in the external set and of 0.82 (95% CI: 0.74-0.89) in the prospective validation set. Using an optimal cutoff, cancer cases were detected with a sensitivity of 86% and a specificity of 90% in the external validation set, and a sensitivity and specificity of 52% and 98% respectively in the prospective validation set. The WID-EC test can identify women with or at risk of endometrial cancer.

DNA methylation-based detection and prediction of cervical intraepithelial neoplasia grade 3 and invasive cervical cancer with the WID™-qCIN test.

BACKGROUND: Cervical screening using primary human papilloma virus (HPV) testing and cytology is being implemented in several countries. Cytology as triage for colposcopy referral suffers from several shortcomings. HPV testing overcomes some of these but lacks specificity in women under 30. Here, we aimed to develop and validate an automatable triage test that is highly sensitive and specific independently of age and sample heterogeneity, and predicts progression to CIN3+ in HPV+ patients. RESULTS: The WID™-qCIN, assessing three regions in human genes DPP6, RALYL, and GSX1, was validated in both a diagnostic (case-control) and predictive setting (nested case-control), in a total of 761 samples. Using a predefined threshold, the sensitivity of the WID™-qCIN test was 100% and 78% to detect invasive cancer and CIN3, respectively. Sensitivity to detect CIN3+ was 65% and 83% for women < and ≥ 30 years of age. The specificity was 90%. Importantly, the WID™-qCIN test identified 52% of ≥ 30-year-old women with a cytology negative (cyt-) index sample who were diagnosed with CIN3 1-4 years after sample donation. CONCLUSION: We identified suitable DNAme regions in an epigenome-wide discovery using HPV+ controls and CIN3+ cases and established the WID™-qCIN, a PCR-based DNAme test. The WID™-qCIN test has a high sensitivity and specificity that may outperform conventional cervical triage tests and can in an objective, cheap, and scalable fashion identify most women with and at risk of (pre-)invasive cervical cancer. However, evaluation was limited to case-control settings and future studies will assess performance and generalisability in a randomised controlled trial.

Glutamatergic systems in neuropathic pain and emerging non-opioid therapies.

Neuropathic pain, a disease of the somatosensory nervous system, afflicts many individuals and adequate management with current pharmacotherapies remains elusive. The glutamatergic system of neurons, receptors and transporters are intimately involved in pain but, to date, there have been few drugs developed that therapeutically modulate this system. Glutamate transporters, or excitatory amino acid transporters (EAATs), remove excess glutamate around pain transmitting neurons to decrease nociception suggesting that the modulation of glutamate transporters may represent a novel approach to the treatment of pain. This review highlights and summarizes (1) the physiology of the glutamatergic system in neuropathic pain, (2) the preclinical evidence for dysregulation of glutamate transport in animal pain models, and (3) emerging novel therapies that modulate glutamate transporters. Successful drug discovery requires continuous focus on basic and translational methods to fully elucidate the etiologies of this disease to enable the development of targeted therapies. Increasing the efficacy of astrocytic EAATs may serve as a new way to successfully treat those suffering from this devastating disease.

The WID-CIN test identifies women with, and at risk of, cervical intraepithelial neoplasia grade 3 and invasive cervical cancer.

BACKGROUND: Cervical screening is transitioning from primary cytology to primary human papillomavirus (HPV) testing. HPV testing is highly sensitive but there is currently no high-specificity triage method for colposcopy referral to detect cervical intraepithelial neoplasia grade 3 or above (CIN3+) in women positive for high-risk (hr) HPV subtypes. An objective, automatable test that could accurately perform triage, independently of sample heterogeneity and age, is urgently required. METHODS: We analyzed DNA methylation at ~850,000 CpG sites across the genome in a total of 1254 cervical liquid-based cytology (LBC) samples from cases of screen-detected histologically verified CIN1-3+ (98% hrHPV-positive) and population-based control women free from any cervical disease (100% hrHPV-positive). Samples were provided by a state-of-the-art population-based cohort biobank and consisted of (i) a discovery set of 170 CIN3+ cases and 202 hrHPV-positive/cytology-negative controls; (ii) a diagnostic validation set of 87 CIN3+, 90 CIN2, 166 CIN1, and 111 hrHPV-positive/cytology-negative controls; and (iii) a predictive validation set of 428 cytology-negative samples (418 hrHPV-positive) of which 210 were diagnosed with CIN3+ in the upcoming 1-4 years and 218 remained disease-free. RESULTS: We developed the WID-CIN (Women's cancer risk IDentification-Cervical Intraepithelial Neoplasia) test, a DNA methylation signature consisting of 5000 CpG sites. The receiver operating characteristic area under the curve (AUC) in the independent diagnostic validation set was 0.92 (95% CI 0.88-0.96). At 75% specificity (≤CIN1), the overall sensitivity to detect CIN3+ is 89.7% (83.3-96.1) in all and 92.7% (85.9-99.6) and 65.6% (49.2-82.1) in women aged ≥30 and <30. In hrHPV-positive/cytology-negative samples in the predictive validation set, the WID-CIN detected 54.8% (48.0-61.5) cases developing 1-4 years after sample donation in all ages or 56.9% (47.6-66.2) and 53.5% (43.7-63.2) in ≥30 and <30-year-old women, at a specificity of 75%. CONCLUSIONS: The WID-CIN test identifies the vast majority of hrHPV-positive women with current CIN3+ lesions. In the absence of cytologic abnormalities, a positive WID-CIN test result is likely to indicate a significantly increased risk of developing CIN3+ in the near future.

Antiprogestins reduce epigenetic field cancerization in breast tissue of young healthy women.

BACKGROUND: Breast cancer is a leading cause of death in premenopausal women. Progesterone drives expansion of luminal progenitor cells, leading to the development of poor-prognostic breast cancers. However, it is not known if antagonising progesterone can prevent breast cancers in humans. We suggest that targeting progesterone signalling could be a means of reducing features which are known to promote breast cancer formation. METHODS: In healthy premenopausal women with and without a BRCA mutation we studied (i) estrogen and progesterone levels in saliva over an entire menstrual cycle (n = 20); (ii) cancer-free normal breast-tissue from a control population who had no family or personal history of breast cancer and equivalently from BRCA1/2 mutation carriers (n = 28); triple negative breast cancer (TNBC) biopsies and healthy breast tissue taken from sites surrounding the TNBC in the same individuals (n = 14); and biopsies of ER+ve/PR+ve stage T1-T2 cancers and healthy breast tissue taken from sites surrounding the cancer in the same individuals (n = 31); and (iii) DNA methylation and DNA mutations in normal breast tissue (before and after treatment) from clinical trials that assessed the potential preventative effects of vitamins and antiprogestins (mifepristone and ulipristal acetate; n = 44). RESULTS: Daily levels of progesterone were higher throughout the menstrual cycle of BRCA1/2 mutation carriers, raising the prospect of targeting progesterone signalling as a means of cancer risk reduction in this population. Furthermore, breast field cancerization DNA methylation signatures reflective of (i) the mitotic age of normal breast epithelium and (ii) the proportion of luminal progenitor cells were increased in breast cancers, indicating that luminal progenitor cells with elevated replicative age are more prone to malignant transformation. The progesterone receptor antagonist mifepristone reduced both the mitotic age and the proportion of luminal progenitor cells in normal breast tissue of all control women and in 64% of BRCA1/2 mutation carriers. These findings were validated by an alternate progesterone receptor antagonist, ulipristal acetate, which yielded similar results. Importantly, mifepristone reduced both the TP53 mutation frequency as well as the number of TP53 mutations in mitotic-age-responders. CONCLUSIONS: These data support the potential usage of antiprogestins for primary prevention of poor-prognostic breast cancers. TRIAL REGISTRATION: Clinical trial 1 Mifepristone treatment prior to insertion of a levonorgestrel releasing intrauterine system for improved bleeding control - a randomized controlled trial, clinicaltrialsregister.eu, 2009-009014-40 ; registered on 20 July 2009. Clinical trial 2 The effect of a progesterone receptor modulator on breast tissue in women with BRCA1 and 2 mutations, clinicaltrials.gov, NCT01898312 ; registered on 07 May 2013. Clinical trial 3 A pilot prevention study of the effects of the anti- progestin Ulipristal Acetate (UA) on surrogate markers of breast cancer risk, clinicaltrialsregister.eu, 2015-001587-19 ; registered on 15 July 2015.

The WID-BC-index identifies women with primary poor prognostic breast cancer based on DNA methylation in cervical samples.

Genetic and non-genetic factors contribute to breast cancer development. An epigenome-based signature capturing these components in easily accessible samples could identify women at risk. Here, we analyse the DNA methylome in 2,818 cervical, 357 and 227 matched buccal and blood samples respectively, and 42 breast tissue samples from women with and without breast cancer. Utilising cervical liquid-based cytology samples, we develop the DNA methylation-based Women's risk IDentification for Breast Cancer index (WID-BC-index) that identifies women with breast cancer with an AUROC (Area Under the Receiver Operator Characteristic) of 0.84 (95% CI: 0.80-0.88) and 0.81 (95% CI: 0.76-0.86) in internal and external validation sets, respectively. CpGs at progesterone receptor binding sites hypomethylated in normal breast tissue of women with breast cancer or in BRCA mutation carriers are also hypomethylated in cervical samples of women with poor prognostic breast cancer. Our data indicate that a systemic epigenetic programming defect is highly prevalent in women who develop breast cancer. Further studies validating the WID-BC-index may enable clinical implementation for monitoring breast cancer risk.

The DNA methylome of cervical cells can predict the presence of ovarian cancer.

The vast majority of epithelial ovarian cancer arises from tissues that are embryologically derived from the Müllerian Duct. Here, we demonstrate that a DNA methylation signature in easy-to-access Müllerian Duct-derived cervical cells from women with and without ovarian cancer (i.e. referred to as the Women's risk IDentification for Ovarian Cancer index or WID-OC-index) is capable of identifying women with an ovarian cancer in the absence of tumour DNA with an AUC of 0.76 and women with an endometrial cancer with an AUC of 0.81. This and the observation that the cervical cell WID-OC-index mimics the epigenetic program of those cells at risk of becoming cancerous in BRCA1/2 germline mutation carriers (i.e. mammary epithelium, fallopian tube fimbriae, prostate) further suggest that the epigenetic misprogramming of cervical cells is an indicator for cancer predisposition. This concept has the potential to advance the field of risk-stratified cancer screening and prevention.

Susceptibility to hormone-mediated cancer is reflected by different tick rates of the epithelial and general epigenetic clock.

BACKGROUND: A variety of epigenetic clocks utilizing DNA methylation changes have been developed; these clocks are either tissue-independent or designed to predict chronological age based on blood or saliva samples. Whether discordant tick rates between tissue-specific and general epigenetic clocks play a role in health and disease has not yet been explored. RESULTS: Here we analyze 1941 cervical cytology samples, which contain a mixture of hormone-sensitive cervical epithelial cells and immune cells, and develop the WID general clock (Women's IDentification of risk), an epigenetic clock that is shared by epithelial and immune cells and optimized for cervical samples. We then develop the WID epithelial clock and WID immune clock, which define epithelial- and immune-specific clocks, respectively. We find that the WID-relative-epithelial-age (WID-REA), defined as the difference between the epithelial and general clocks, is significantly reduced in cervical samples from pre-menopausal women with breast cancer (OR 2.7, 95% CI 1.28-5.72). We find the same effect in normal breast tissue samples from pre-menopausal women at high risk of breast cancer and show that potential risk reducing anti-progesterone drugs can reverse this. In post-menopausal women, this directionality is reversed. Hormone replacement therapy consistently leads to a significantly lower WID-REA in cancer-free women, but not in post-menopausal women with breast or ovarian cancer. CONCLUSIONS: Our findings imply that there are multiple epigenetic clocks, many of which are tissue-specific, and that the differential tick rate between these clocks may be an informative surrogate measure of disease risk.

Toll-Like Receptors (TLRs) in Health and Disease: An Overview.

Toll-like receptors were discovered as proteins playing a crucial role in the dorsoventral patterning during embryonic development in the Drosophila melanogaster (D. melanogaster) almost 40 years ago. Subsequently, further research also showed a role of the Toll protein or Toll receptor in the recognition of Gram-positive bacterial and fungal pathogens infecting D. melanogaster. In 1997, the human homolog was reported and the receptor was named the Toll-like receptor 4 (TLR4) that recognizes lipopolysaccharide (LPS) of the Gram-negative bacteria as a pathogen-associated molecular pattern (PAMP). Identification of TLR4 in humans filled the long existing gap in the field of infection and immunity, addressing the mystery surrounding the recognition of foreign pathogens/microbes by the immune system. It is now known that mammals (mice and humans) express 13 different TLRs that are expressed on the outer cell membrane or intracellularly, and which recognize different PAMPs or microbe-associated molecular patterns (MAMPs) and death/damage-associated molecular patterns (DAMPs) to initiate the protective immune response. However, their dysregulation generates profound and prolonged pro-inflammatory immune responses responsible for different inflammatory and immune-mediated diseases. This chapter provides an overview of TLRs in the control of the immune response, their association with different diseases, including TLR single nucleotide polymorphisms (SNPs), interactions with microRNAs (miRs), use in drug development and vaccine design, and expansion in neurosciences to include pain, addiction, metabolism, reproduction, and wound healing.

Chemokine receptor antagonists enhance morphine's antinociceptive effect but not respiratory depression.

AIMS: We have shown that chemokines injected into the periaqueductal gray region of the brain blocks opioid-induced analgesia in the rat cold-water tail flick test (CWTF). The present experiments tested whether chemokine receptor antagonists (CRAs), in combination with sub-analgesic doses of morphine, would provide maximal analgesia in the CWTF test and the mouse formalin pain assay. The effect of CRAs on respiratory depression was also evaluated. MAIN METHODS: One, two or four CRAs (AMD3100/CXCR4, maraviroc/CCR5, RS504393/CCR2 orAZD8797/CX3CR1) were used in combination with sub-analgesic doses of morphine, all given systemically. Pain was assessed using the rat CWTF test or formalin injection into the paw of mice scored by licking. Respiration and oxygen saturation were measured in rats using a MouseOX® Plus - pulse oximeter. KEY FINDINGS: In the CWTF test, a sub-maximal dose of morphine in combination with maraviroc alone, maraviroc plus AMD3100, or with the four chemokine receptor antagonists, produced synergistic increases in antinociception. In the formalin test, the combination of four CRAs plus a sub-maximal dose of morphine resulted in increased antinociception in both male and female mice. AMD3100 had an additive effect with morphine in both sexes. Coadministration of CRAs with morphine did not potentiate the opioid respiratory depressive effect. SIGNIFICANCE: These results support the conclusion that combinations of CRAs can increase the potency of sub-analgesic doses of morphine analgesia without increasing respiratory depression. The results support an "opioid sparing" strategy for alleviation of pain using reduced doses of opioids in combination with CRAs to achieve maximal analgesia.

Monte Carlo simulation of uncertainty to identify barriers to optimizing blood pressure control.

OBJECTIVES: To assess the impact of variable drug response and measurement error on SBP control. METHODS: We simulated a treat-to-target strategy for populations with different pretreatment SBP, whereby medications were added sequentially until measured SBP (mSBP) less than 140 mmHg. Monte Carlo simulations determined variability of both drug response (drugeff ±â€Šσdrug; 10 ±â€Š5 mmHg base case) and measurement error (σmeas; 10 mmHg base case) of true SBP (tSBP). The primary outcome measure was the proportion of individuals who achieved target less than 140 mmHg. RESULTS: Decision-making based on mSBP resulted in 35.0% of individuals with initial tSBP 150 mmHg being either inappropriately given, or inappropriately denied a second drug. When the simulation was run for multiple drug titrations, measurement error limited tSBP control for all populations tested. A strategy of drug titration based on a second measurement for individuals at risk of incorrect decisions (mSBP 120-150 mmHg; σmeas 15 mmHg) reduced the proportion above target from 40.1 to 30.0% when initial tSBP 160 mmHg. When the measurement variability for the second reading was reduced below that usually seen in clinical practice (σmeas 5 mmHg), the proportion above target decreased further to 17.4%. CONCLUSION: In this simulation, measurement error had the greatest impact on the proportion of individuals achieving their SBP target. Efforts to reduce this error through repeated measures, alternative measurement techniques or changing thresholds, are promising strategies to reduce cardiovascular morbidity and mortality and should be investigated in clinical trials. Here we have shown that Monte Carlo simulations are a useful technique to investigate the influence of uncertainty for different hypertension management strategies.

Selective recruitment designs for improving observational studies using electronic health records.

Large-scale electronic health records (EHRs) present an opportunity to quickly identify suitable individuals in order to directly invite them to participate in an observational study. EHRs can contain data from millions of individuals, raising the question of how to optimally select a cohort of size n from a larger pool of size N. In this article, we propose a simple selective recruitment protocol that selects a cohort in which covariates of interest tend to have a uniform distribution. We show that selectively recruited cohorts potentially offer greater statistical power and more accurate parameter estimates than randomly selected cohorts. Our protocol can be applied to studies with multiple categorical and continuous covariates. We apply our protocol to a numerically simulated prospective observational study using an EHR database of stable acute coronary disease patients from 82 089 individuals in the U.K. Selective recruitment designs require a smaller sample size, leading to more efficient and cost-effective studies.

Genetic association of FKBP5 with PTSD in US service members deployed to Iraq and Afghanistan.

Post-traumatic stress disorder (PTSD) is a debilitating mental disorder with a prevalence of more than 7% in the US population and 12% in the military. An interaction of childhood trauma with FKBP5 (a glucocorticoid-regulated immunophilin) has been reported to be associated with PTSD in the general population. However, there are few reports on the association of FKBP5 with PTSD, particularly in important high-risk population such as the military. Here, we examined the association between four single-nucleotide polymorphisms (SNPs; rs3800373, rs9296158, rs1360780, rs9470080) covering the FKBP5 gene and probable PTSD in US service members deployed to Iraq and Afghanistan, a high-risk military population (n = 3890) (Hines et al., 2014). We found that probable PTSD subjects were significantly more likely to carry the A-allele of rs3800373, G-allele of rs9296158, C-allele of rs1360780, and C-allele of rs9470080. Furthermore, the four SNPs were in one block of strong pairwise linkage disequilibrium (r = 0.91-0.96). Within the block there were two major haplotypes of CATT and AGCC (rs3800373-rs9296158-rs1360780-rs9470080) that account for 99% of haplotype diversity. The distribution of the AGCC haplotype was significantly higher in probable PTSD subjects compared to non-PTSD (p<.05). The diplotype-based analysis indicated that the AGCC carriers tended to be probable PTSD. In this study, we demonstrated the association between FKBP5 and probable PTSD in US service members deployed to Iraq and Afghanistan, indicating that FKBP5 might be a risk factor for PTSD.

HER2-HER3 Heterodimer Quantification by FRET-FLIM and Patient Subclass Analysis of the COIN Colorectal Trial.

BACKGROUND: The phase III MRC COIN trial showed no statistically significant benefit from adding the EGFR-target cetuximab to oxaliplatin-based chemotherapy in first-line treatment of advanced colorectal cancer. This study exploits additional information on HER2-HER3 dimerization to achieve patient stratification and reveal previously hidden subgroups of patients who had differing disease progression and treatment response. METHODS: HER2-HER3 dimerization was quantified by fluorescence lifetime imaging microscopy in primary tumor samples from 550 COIN trial patients receiving oxaliplatin and fluoropyrimidine chemotherapy with or without cetuximab. Bayesian latent class analysis and covariate reduction was performed to analyze the effects of HER2-HER3 dimer, RAS mutation, and cetuximab on progression-free survival and overall survival (OS). All statistical tests were two-sided. RESULTS: Latent class analysis on a cohort of 398 patients revealed two patient subclasses with differing prognoses (median OS = 1624 days [95% confidence interval [CI] = 1466 to 1816 days] vs 461 days [95% CI = 431 to 504 days]): Class 1 (15.6%) showed a benefit from cetuximab in OS (hazard ratio = 0.43, 95% CI = 0.25 to 0.76, P = .004). Class 2 showed an association of increased HER2-HER3 with better OS (hazard ratio = 0.64, 95% CI = 0.44 to 0.94, P = .02). A class prediction signature was formed and tested on an independent validation cohort (n = 152) validating the prognostic utility of the dimer assay. Similar subclasses were also discovered in full trial dataset (n = 1630) based on 10 baseline clinicopathological and genetic covariates. CONCLUSIONS: Our work suggests that the combined use of HER dimer imaging and conventional mutation analyses will be able to identify a small subclass of patients (>10%) who will have better prognosis following chemotherapy. A larger prospective cohort will be required to confirm its utility in predicting the outcome of anti-EGFR treatment.

Perspectives of Pharmacology over the Past 100 Years.

It is fitting that the 100th anniversary of the Handbook of Experimental Pharmacology celebrates not only its founding but also the founding of experimental pharmacology as both had their beginnings in Germany. Founded in 1919 by Arthur Heffter (1859-1925) as the "Handbuch der Experimentellen Pharmakologie" and renamed to its current title in 1937, the Handbook has continued to capture the emergence and developments of experimental pharmacology since the initial systematic work of Rudolf Buchheim and his student Oswald Schmiedeberg. Heffter, the first Chairman of the German Society of Pharmacology, was also responsible for isolating mescaline as the active psychedelic component from the peyote cactus, thereby initiating a series of studies along with an Institute that, much like the Handbook and the discipline of pharmacology, continues to discover and disseminate new findings to this day. These early endeavors to establish pharmacology as a viable and valuable contributor to the medical sciences met with considerable resistance and challenges. However, the persistence and dedication of these early pharmacologists placed pharmacology on a firm foundation from which to spread this discipline globally, leading ultimately to our current understanding of the principles of drug action and with an impact likely unanticipated by these founding scientists. Summarizing the beginnings of these efforts and their early spread to other countries provides an appropriate context in which to document the many contributions pharmacological research has made over the past 100 years and provide an opportunity to anticipate expectations around its future developments.

Neuronal Circuit-Based Computer Modeling as a Phenotypic Strategy for CNS R&D.

With the success rate of drugs for CNS indications at an all-time low, new approaches are needed to turn the tide of failed clinical trials. This paper reviews the history of CNS drug Discovery over the last 60 years and proposes a new paradigm based on the lessons learned. The initial wave of successful therapeutics discovered using careful clinical observations was followed by an emphasis on a phenotypic target-agnostic approach, often leading to successful drugs with a rich pharmacology. The subsequent introduction of molecular biology and the focus on a target-driven strategy has largely dominated drug discovery efforts over the last 30 years, but has not increased the probability of success, because these highly selective molecules are unlikely to address the complex pathological phenotypes of most CNS disorders. In many cases, reliance on preclinical animal models has lacked robust translational power. We argue that Quantitative Systems Pharmacology (QSP), a mechanism-based computer model of biological processes informed by preclinical knowledge and enhanced by neuroimaging and clinical data could be a new powerful knowledge generator engine and paradigm for rational polypharmacy. Progress in the academic discipline of computational neurosciences, allows one to model the effect of pathology and therapeutic interventions on neuronal circuit firing activity that can relate to clinical phenotypes, driven by complex properties of specific brain region activation states. The model is validated by optimizing the correlation between relevant emergent properties of these neuronal circuits and historical clinical and imaging datasets. A rationally designed polypharmacy target profile will be discovered using reverse engineering and sensitivity analysis. Small molecules will be identified using a combination of Artificial Intelligence methods and computational modeling, tested subsequently in heterologous cellular systems with human targets. Animal models will be used to establish target engagement and for ADME-Tox, with the QSP approach complemented by in vivo preclinical models that can be further refined to increase predictive validity. The QSP platform can also mitigate the variability in clinical trials with the concept of virtual patients. Because the QSP platform integrates knowledge from a wide variety of sources in an actionable simulation, it offers the possibility of substantially improving the success rate of CNS R&D programs while, at the same time, reducing both cost and the number of animals.