The stromal elements of a malignant tumor can promote cancer progression and metastasis. The structure of the tumor stroma includes connective tissue elements, blood vessels, nerves, and extracellular matrix (ECM). Some of the cellular elements of the tumor stroma are cancer-associated f ibroblasts (CAFs). The origin and function of CAFs have been actively studied over the past thirty years. CAFs produce collagen, the main scaffold protein of the extracellular matrix. Collagen in the tumor stroma stimulates f ibrosis, enhances the rigidity of tumor tissue, and disrupts the transmission of proliferation and differentiation signaling pathways. CAFs control tumor angiogenesis, cell motility, tumor immunogenic properties, and the development of resistance to chemo- and immunotherapy. As a result of metabolic adaptation of rapidly growing tumor tissue to the nutrients and oxygen deprivation, the main type of energy production in cells changes from oxidative phosphorylation to anaerobic glycolysis. These changes lead to sequential molecular alterations, including the induction of specif ied transcriptional factors that result in the CAFs activation. The molecular phenotype of activated CAFs is similar to f ibroblasts activated during inf lammation. In activated CAFs, alpha-smooth muscle actin (α-SMA) is synthetized de novo and various proteases and f ibronectin are produced. Since CAFs are found in all types of carcinomas, these cells are potential targetsfor the development of new approaches for anticancer therapy. Some CAFs originate from resident f ibroblastsof the organs invaded by the tumor, while others originate from epithelial tumor cells, which are undergoing anepithelial-mesenchymal transition (EMT). To date, many molecular and metabolic inducers of the EMT have beendiscovered including the transforming growth factor-beta (TGF-β), hypoxia, and inf lammation. This review classifies modern concepts of molecular markers of CAFs, their functional features, and discusses the stages of epithelial-mesenchymal transition, and the potential of CAFs as a target for antitumor therapy Modern concept of tumor morphology postulates that solidtumors are formed by epithelial and stromal cells, such asfibroblasts, endothelial cells, and immune cells . Stromal cells with a fibroblast-like phenotype, theso-called cancer-associated fibroblasts (CAFs), in contrast tonormal fibroblasts, contain various chromosomal abnormalities,such as duplications, multiple rearrangements, and eventhe loss of entire chromosomes . CAFscontrol tumor angiogenesis, motility and metastasis of cancercells, tumor immunogenic properties, and the developmentof resistance to chemotherapy and immunotherapy .A meta-analysis of the clinical relevance of the tumorstroma has demonstrated the association of high CAFs contentwith the advanced stages of tumor progression, as wellas with the high risk of local recurrence after tumor resection.In 1995, a heterogeneous origin of CAFs was hypothesizedby Rønnov-Jessen and colleagues, who showed that breastcancer CAFs can originate from resident fibroblasts, vascularsmooth muscle cells, and pericytes .To date, it has been shown that precursors of mesenchymalcells from the red bone marrow, endothelial and epithelialcells, resident fibroblasts of the affected tissue, adipocytesand vascular adventitia cells can be sources of CAFs . For the initiation of theCAFs phenotype in some progenitor cells, additional stimulationwith cytokines and growth factors, such as transforminggrowth factor beta (TGF-β), fibroblast growth factor (FGF),and other signaling molecules is required (Table 1) .Tumor epithelial cells can undergo transformation intoCAFs via the epithelial-mesenchymal transition (EMT). EMT is a dynamic process of transdifferentiation ofepithelial cells into fibroblast-like cells. The EMT plays animportant role not only in cancer, but also in embryogenesisand regeneration. In particular, EMT occurs in embryonic stemcells producing mesoderm and neural crest, and in skin cellsduring wound healing . Dynamic changesin cell morphology during EMT are caused by changes inthe regulatory genes’ expression with production of certainproteins. These proteins are considered as EMT markers. Among these markers, the most significant areN-cadherin and vimentin, which are responsible for the rearrangementof the cytoskeleton and the change in the shapeof the cell, as well as the change in cell-to-cell and cell-toextracellularmatrix (ECM) interactions .In addition to molecular inducers of EMT, the importantrole of hypoxic conditions has been shown. Hypoxia activatesEMT via the binding of the hypoxia-inducible factor (HIF-1)to the promoters of genes responsible for EMT activation.HIF-1 has been shown to increase the expression of the transcriptionfactors genes of the zinc finger motif family such asZEB1, Snail and SLUG. Overexpression of these factors isassociated with the mesenchymal phenotype and a decreasein the abundance of epithelial cell markers – E-cadherin andtype 1 tight junction protein (TJP1 or ZO-1) .Endothelial cells of tumor vessels can undergo an endothelial-mesenchymal transition (EndMT) and acquire thephenotype and functional features of CAFs with the loss ofendothelial cells molecular markers, such as the endothelialcell/platelet adhesion molecule (CD31), and the acquisition ofmarkers specific for mesenchymal cells, such as α-SMA andfibroblast specific protein 1 (FSP-1) .An important component of breast cancer stroma areadipose cells, which can transform into tumor-associatedadipocytes, and then into CAFs. Such changes are accompaniedby an increase in the expression of molecular markersof mesenchymal cells, including, PPARG (receptors inducedby peroxisome activators gamma), RUNX-2 (transcriptionfactor containing the Runt type 2 DNA-binding domain), andSOX9 (transcription factor of the HMG family DNA-bindingproteins) .Using the model of prostate cancer, it was shown thatmesenchymal stem cells (MSCs) can differentiate into CAFsafter the activation of the chemokine receptor type 6 (CXCR6)by its ligand CXCL16. Moreover, the activation of CXCR6results in the secretion of stromal factor-1 (CXCL12) involvedin EMT . Weber and colleagues also showedthat the extracellular structural protein osteopontin (OPN),which plays a key role in bone formation, activates TGF-βgene expression in integrin-dependent MSCs to maintain thephenotype of CAFs in breast cancer. Interestingly, even specializedcells such as Ito cells in the liver, pancreatic stellatecells, and mammary myofibroblasts can acquire the phenotypeof CAFs . These examples illustrate a widerange of cells that, responding to the molecular changes ina tumor, are able to acquire the CAFs’ phenotype and, as aconsequence, be involved in tumor homeostasis.The involvement of CAFs in carcinogenesis and tumor progressionmakes them a potential target for the developmentof novel therapeutic approaches. A potentially clinicallysignificant marker of CAF is the transmembrane mucin-likeprotein podoplanin (PDPN) (Table 2); to date, PDPN has beendescribed as a marker of lymphoid capillary progenitor cellsand CAFs in lung cancers. Expression of podoplanin wasshowed in 54 (30.5 %) out of 177 CAFs’ populations studied inthe work of Yurugi et al. Interestingly, all podoplanin-positiveCAFs correlated with invasiveness of adenocarcinomas, whilea podoplanin-negative phenotype was shown only in noninvasiveadenocarcinomas .Platelet-derived growth factor receptors α/β are importantmarkers of CAFs. PDGFRα/β belong to the 3rd class oftyrosine kinases and are activated by interaction with thePDGF ligand. PDGFR regulates the organogenesis of varioussystems during embryogenesis; however, the significanceof the PDGFRα and -β receptors activation in tumors is stillpoorly understood. It has been shown that the expression ofthe PDGFRβ receptor is increased in the tumor microenvironmentcells, where platelet growth factor activates CAFsand, probably, stimulates cancer progression . PDGFRα-positive CAFs have been found in thestroma of melanoma, suggesting that these CAFs originatefrom resident fibroblasts as a result of their activation . Serum amyloid A (SAA-1) protein is one of thepotential targets of CAFs; its expression and involvementin tumor progression has been shown in CAFs from gastrictumors .In the search for specific markers of the tumor stroma cells,among the CAFs of prostate adenocarcinoma, an increasedcontent of the surface protein with a single V-domain of immunoglobulin(CD90), initially found on T cells and neurons,was identified as a specific marker. The high level of CD90 onthe cell surface differentiates the tumor-associated stroma and “benign” stroma. Since CD90 expression was shown only intumor associated fibroblasts, this marker is a potential targetfor therapy .Certain CAFs proteins can be prognostic markers of tumorinvasiveness. One of these markers is a protein from the familyof low molecular weight calcium-binding proteins ofthe S100 – S100A4 family . S100 familyproteins have both intracellular and extracellular activitydue to maintaining the calcium balance and Ca2+-dependentprocesses. S100A4 activates a cascade of reactions associatedmainly with the secretion of pro-inflammatory cytokines andthe expression of growth factors, extracellular matrix proteins,metalloproteinases, and others. Intracellular activity ofS100A4 is of particular interest, and is associated with theenhancement of the invasive capabilities of tumor cells, theirescape from apoptosis, and the stem phenotype of the cells. During the study of the role ofS100A4 in tumor progression, it was shown that suppressionof S100A4 decreased tumor growth . The role of stromal cells thatsecrete S100A4 was shown in the MMTV-PyVmT mousemodel with the S100A4 knocked-out gene during orthotopicco-transplantation of CSML100 mouse mammary adenocarcinomacells and MEF mouse embryonic fibroblasts. MEFcell lines were obtained by spontaneous immortalization ofprimary embryonic fibroblasts from mouse embryos with theS100A4+ and S100A4– phenotypes. Upon co-transplantationof tumor cells and fibroblasts with the S100A4– phenotypein syngeneic mice, no metastases were formed, however,upon transplantation of S100A4+ fibroblasts, the metastaticpotential of tumor cells returned. S100A4+ fibroblasts werecharacterized by increased mobility and invasiveness comparedto S100A4– fibroblasts, as well as the ability to secreteS100A4 into the tumor microenvironment .To date, it is clear that the expression of certain CAFsmarkers does not unambiguously predict the aggressivenessof the tumor. For example, the loss of caveolin-1 in breastcancer CAFs has been shown to be associated with a poorprognosis because the population of these cells stimulates thegrowth of triple negative (ER-/PR-/HER2-) breast cancer cells. In a parallel study, the expression ofcaveolin-1 in the breast cancer CAFs stimulated the remodelingof the tumor microenvironment, thereby facilitating theinvasion of malignant cells and an increased invasiveness levelcorrelated with the metastatic potential of the tumor . These contradictingresultsindicate the diverse role of caveolin-1 in histologicallydifferent tumors. More studies should be made to determinecaveolin-1 as a tumor prognostic marker.CAFs-dependent stimulation of the tumor cells proliferationand their invasion is of particular interest in the study oftumor. This interest is primarily due to the fact that even inthe precancerous phenotype of epithelial cells, some residentfibroblasts are already transformed into CAFs . Fibroblasts from intestinal tumors and polyps werea good model to confirm the contribution of stromal cells totumor growth and progression. These fibroblasts were shownto stimulate the proliferation of tumor and polyp cells .The interaction of tumor epithelial cells with CAFs wasanalyzed by comparing the histological picture of varioustypes of gastric cancer. In a study by Orimo and Weinberg,it was demonstrated that in the case of diffuse gastric cancer,CAFs and epithelial cells are more closely spaced, while inthe intestinal type, CAFs form a stroma-like matrix, due towhich tumor epithelial cells retain their glandular structure.Using the model of heterogeneous 3D spheroids, consistingof breast cancer epithelial cells and fibroblasts, Dang and colleaguesshowed that CAFs stimulated the migration of tumorcells of basal breast cancer (ER-/PR-/HER2-). Interestingly,this effect was not observed in the models of luminal breastcancer types  . These data are consistent with clinical observationsindicating a higher percentage of metastasis in triplenegativebreast cancer compared with other types of breast tumors. However, which factors make cells of basal breastcancer sensitive to CAFs stimulation remain undiscovered.In order to reach the blood and lymphatic streams, tumorcells should pass through the basement membrane (BM), separatingthem from connective tissue and vessels. Thus, CAFsare able to synthesize metalloproteinases – endopeptidasescapable of destroying proteins of all types of the BM extracellularmatrix . In 2017, Glentis andcolleagues revealed a metalloproteinase-independent CAFssupportedovercome of BM by tumor cells. They demonstratedthe ability of CAFs to stretch BM with the formation of pores,and through these pores, epithelial tumor cells and CAFs canmigrate into the bloodstream and form metastases in distantorgans. Interestingly, BM regions with low expression oflamininand type IV collagen exhibited the highest tendencyfor stretching . This alternative CAFsdependentmigration pathway explains the ineffectiveness ofthe metalloproteinase inhibitors application in patients withhead and neck tumors.The paracrine secretion of IL-1α by CAFs in bladder cancerwith further activation of the Wnt pathway in tumor cells isthe perfect illustration of the pro-carcinogenic role of CAFs. Moreover, bladder cancer СAFs secretingIL-8 are able to stimulate the secretion of neuropilin-1,which enhances the proliferation of tumor cells and is oneof the potential prognostic markers of malignancy . Interestingly, recent studies have shown thatneuropilin-1 may be a co-factor in the induction of EMT.Paracrine stimulation of the epithelial-mesenchymal transitionin tumor epithelial cells by CAFs is an important factorcontributing to tumor progression. The central mechanism ofEMT in the tumor is the TGF-β/Smad pathway activation,induced by TGF-β from stromal fibroblasts  . The Smad factor is a transcription factor that controlsthe expression of EMT genes. Vered and colleagues showedthat cells with EMT markers are found in primary foci ofsquamous cell carcinoma of the tongue as well as in regionallymph nodes metastases. This confirms the importance of CAFs in the induction of metastasis and in the formation ofa secondary tumor node .The central mechanism of the EMT activation in ovariancancer is the induction of the CXCR4/Wnt/β-catenin pathwayin tumor epithelial cells. CAFs secreting stromal growth factor-1 (SDF-1 or CXCL12) have been shown to be the majorplayers in this process. Moreover, SDF-1 is also interlinkedwith the resistance of tumor cells to chemotherapeutic agentssuch as cisplatin .In 2020, Franzè and colleagues demonstrated the activationof CAFs phenotype in normal fibroblasts from rectal polypsco-cultured with CAFs. They showed that CAFs derivedfrom colorectal tumors can secrete IL-34, which in normalfibroblasts activates the expression of CAFs markers suchas α-SMA, vimentin, and fibroblast activating protein (FAP).Even though most of the described functions of СAFs areassociated with the stimulation of tumor progression, someauthors also describe СAFs as tumor-suppressing players. Forexample, the subpopulation of CAFs expressing the melanomaadhesion molecule (CD146) in breast tumors correlated witha retarded cell proliferation in estrogen-dependent types ofbreast cancer . Since CAFs secretecytokines involved in the recruitment and maturation ofmacrophages, T-lymphocytes and natural killer cells , they increase the availabilityof the tumor to immune cells and promote antitumor immuneresponse . In the study of oral cancer,it was also shown that CAFs can suppress the proliferationof tumor cells. In particular, the population of CAFs secretingBone Morphogenetic Protein 4 (BMP4) and expressingα-SMA inhibited the proliferation of cancer stem cells (CSC). Using the mice model with a predispositionfor the development of pancreatic cancer, Rhim and colleaguesexhibited the role of CAFs in cancer progression. They excludedthe α-SMA-positive population of CAFs or CAFs withinhibited Hedgehog signaling pathway. These modificationssuppress the growth of pancreatic ductal adenocarcinoma.Histological analysis of tumors revealed abnormalities in thevessel’s formation .These examples demonstrate the tumor-suppressing functionof CAFs only in high differentiated cancers with nosimilarity in undifferentiated ones. It can be assumed thatapart from origin and tissue of the affected organ, the functionof CAFs is determined by the differentiation stage of cancercells .Cell cultures obtained from patients’ tumors after surgery aremost often used to study the properties of CAFs. It is necessaryto establish new CAFs cell cultures, since in vitro CAFs tendto age rapidly, and the possibilities of their use are limitedby early passages . Moreover, in commerciallyavailable cell collections American Type CultureCollection (ATCC), European Collection of AuthenticatedCell Cultures (ECACC), Russian collection of cell cultures,etc. cell lines with the CAFs phenotype are limited. For instance,in ATCC, only one CAFs cell line is available. Thiscell culture originates from the prostate adenocarcinoma and ismodified by the introduction of the telomerase transgene underthe control of the constitutive promoter of the polyoma virusSV40 hTERT PF179T CAF. This modification of fibroblastsis aimed at maintaining the proliferative properties of CAFs.To obtain cell cultures from tumor tissue, mechanical disaggregation,enzymatic dissociation, chelation and their combinationare used. Trypsin and type IV collagenase are mostoften used to destroy the stroma of tumor tissue. The choice ofwhat technique to use should consider the histological originof the tissue of interest. When tissue disaggregated, CAFs canrepresent a small population of cells and obtaining a monoculturerequires an additional stage of their separation fromthe total cell mass. In order to isolate a particular populationof CAFs, magnetic separation, or FACS of cells with immunostainingof specific CAFs markers such as FAP or α-SMAare used . The main difficulty in isolating CAFs lies in adaptingprotocols for vital staining of intracellular markers such asα-SMA, FAP, and vimentin. Therefore, it is highly desirableto include surface markers such as CD90 in the analysis.Clear understanding the tumor microenvironment role iscrucial for the development of new approaches in cancer diagnosticsand treatment. The multifaceted influence of CAFson tumor progression makes them an important object for thestudy of carcinogenesis and the development of new antitumoragents. The use of drugs targeted to the components of thetumor microenvironment has not demonstrated efficacy foranti-metalloproteinase compounds and angiogenesis inhibitorsas well as T-cell immunity checkpoints inhibitors in sometypes of cancer . The heterogeneity ofthe molecular phenotypes of CAFs can be an important factorin the failure of CAF-targeted cancer treatment. The scientificcommunity should develop more detailed classifications ofvarious subtypes of CAFs considering their involvement intumor progression.Thus, a detailed classification of CAFs and a study of thefunctions of each phenotypic subgroup may provide importantknowledge for the development of new methodsfor the CAF-related treatment and diagnosis of oncologicaldiseases.The authors declare no conflict of interest.Alkasalias T., Moyano-Galceran L., Arsenian-Henriksson M., Lehti K.Fibroblasts in the tumor microenvironment: shield or spear? Int. J.Mol. Sci. 2018;19(5):1532. 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Metabolic comorbidities including diabetes (DM) and dyslipidemia pose challenges to the long-term care of people with HIV (PWH). Incidence of cardiovascular disease and DM are reported at higher rates in PWH than the general population. Obesity is broadly prevalent in both the general population and PWH, and higher body mass index (BMI) can contribute to metabolic complications. Here we present longer-term follow up on incidence of DM, hypertension (HTN), BMI categorical shifts, and lipid changes over 144 weeks of blinded treatment from two trials of PWH initiating antiretroviral therapy.We assessed incidence of metabolic complications in adult PWH in Study 1489: bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) vs dolutegravir/abacavir/ lamivudine (DTG/ABC/3TC) and Study 1490: B/F/TAF vs DTG+F/TAF. Treatment-emergent (TE) metabolic comorbidities were defined by standard MedDRA search lists. CDC-defined BMI categories were compared from baseline (BL) to Week 144. Analyses by sex at birth and race were performed, as well as for lipid changes.Among 1,274 total participants, median (range) age was 33 years (18-77), 90% men, 33% black. In study 1489, BL prevalence of DM and HTN was 4.5 and 12.1% with TE DM and HTN in B/F/TAF being 0.7% and 10%, and for DTG/ABC/3TC 1.3% and 6.9%, respectively. In study 1490, BL prevalence of DM and HTN was 6.8 and 18.8% with TE DM and HTN in B/F/TAF being 2.1 and 5.8%, and for DTG+F/TAF 2.3 and 6.5%, respectively. BMI shift from Normal to Obese: B/F/TAF 0%, DTG/ABC/3TC 3.2%, p=0.12 (1489) (Table 1); B/F/TAF 2.5%, DTG+F/TAF 2.9% p=1.00 (1490) (Table 2). Subgroup analyses by gender/race showed similar findings for TE DM, HTN, and BMI changes. Median changes from BL fasted lipids were small (Table 1).Table 1§. Studies 1489 and 1490: Metabolic Outcomes from Baseline to Week 144Table 2±. Shift Table of BMI Category at Week 144 by Baseline BMI Category – OverallThrough over 144 weeks of follow up, PWH randomized to initiate B/F/TAF, DTG/ABC/3TC or DTG+F/TAF had low rates of incident DM or HTN-related AEs, with no statistically significant differences by treatment group. BMI changes/categorical shifts from BL did not significantly differ by regimen, and no clinically significant change or difference by regimen in lipids were observed. While data are limited by three years of follow up, they are strengthened by randomized study design of three widely used initial ART regimens.Eric Daar, MD, Bristol-Myers Squibb (Consultant)Gilead Sciences Inc. Janssen Merck Teva ViiV Healthcare  Chloe Orkin, MD, Gilead Sciences Inc. Janssen Merck ViiV Healthcare  Paul Sax, MD, Gilead Sciences Janssen (Consultant)Merck ViiV  Jeffrey L. Stephens, MD, Gilead Sciences Inc.  Ellen Koenig, MD, Gilead Sciences Inc. (Scientific Research Study Investigator) Amanda Clarke, MD, Gilead Sciences Inc. ViiV Healthcare  Axel Baumgarten, MD, AbbVie Bristol-Myers Squibb Gilead Sciences Inc. Janssen (Speaker’s Bureau)Merck (Advisor or Review Panel member) Cynthia Brinson, MD, Abbvie (Scientific Research Study Investigator)BI (Scientific Research Study Investigator)Gilead Sciences Inc. GSK (Scientific Research Study Investigator)Novo Nordisk (Scientific Research Study Investigator)ViiV Healthcare  Moti Ramgopal, MD FIDSA, Abbvie Gilead Janssen Merck ViiV  Hailin Huang, PhD, Gilead Sciences Inc.  Terry Farrow, MD, Gilead Sciences Inc.  Jared Baeten, MD, PHD, Gilead Sciences Inc.  Jason Hindman, PharmD, Gilead Sciences Inc.  Hal Martin, MD, MPH, Gilead Sciences Inc.  Kimberly Workowski, MD, Nothing to disclose


Cabotegravir (CAB) plus rilpivirine (RPV) is the first complete long-acting (LA) regimen recommended by treatment guidelines for the maintenance of HIV-1 virologic suppression. CAB+RPV LA dosed every 4 weeks (Q4W) or every 8 weeks (Q8W) demonstrated noninferior efficacy in multinational Phase 3/3b trials. This This analysis focuses on data for US/CAN participants naive to CAB+RPV (n=376) from the larger pooled population of the ATLAS, FLAIR, and ATLAS-2M Phase 3/3b studies (N=1245). Endpoints included the proportion of participants with plasma HIV-1 RNA ≥ 50 and < 50 c/mL at W48 , incidence of confirmed virologic failure , safety, and treatment preference through W48.2) previously associated with CVF. Among the US/CAN participants with a single baseline factor, none met CVF. Overall, archived RPV RAMs were observed in 3.2% (12/376), HIV subtype A6/A1 in 1.1% (4/376), and BMI ≥ 30 kg/m2 in 26.3% (99/376) of participants. Safety and injection site reaction findings were similar to the overall pooled population (Table 2). Most participants  preferred LA over oral dosing . 376 US/CAN participants received CAB+RPV LA Q4W or Q8W. Median (range) age was 39y (20–74); 14.9% were female, 66.0% were White. At W48, 93.1% (350/376) maintained virologic suppression (HIV-1 RNA < 50 c/mL), 1.9% (7/376) had HIV-1 RNA ≥ 50 c/mL, and 0.8% (3/376) met the CVF criterion, consistent with the overall global pooled population (Table 1). Two of the three participants with CVF had ≥ 2 of the three baseline factors Table 2. Safety summary through Week 48 following CAB+RPV LA Q4W and Q8W or comparator ART in participants naive to CAB+RPV from ATLAS, FLAIR, and ATLAS-2MIn US/CAN Phase 3/3b trial participants, CAB+RPV LA was highly effective and well tolerated, with outcomes consistent with the overall pooled population. Baseline prevalence of archived RPV RAMs and subtype A6/A1 was low and aligned with regional prevalence/surveillance data. CAB+RPV LA provides a tolerable and effective injectable LA treatment option for virologically suppressed US/CAN individuals with HIV.Babafemi O. Taiwo, MBBS, Gilead (Consultant)Merck (Consultant)ViiV Healthcare (Consultant) Darrell Tan, MD PhD, Abbvie (Grant/Research Support)Gilead (Grant/Research Support)GlaxoSmithKline (Scientific Research Study Investigator)ViiV Healthcare (Grant/Research Support) Parul Patel, PharmD, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Paula Teichner, PharmD, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Joseph Polli, PhD, FAAPS, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Louise Garside, PhD, GlaxoSmithKline (Employee) Ronald D’Amico, DO, MSc, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Christine L. Talarico, M.S., GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Rodica Van Solingen-Ristea, MD, Janssen Research and Development (Employee)ViiV Healthcare (Employee) Bryan Baugh, MD, Janssen, Johnson & Johnson  William Spreen, PharmD, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Michael Aboud, MBChB, MRCP, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee) Matthew Bosse, DO, GlaxoSmithKline (Shareholder)ViiV Healthcare (Employee)


Dengue fever is a mosquito-borne viral disease endemic in 128 countries. An unmet clinical need remains for an effective vaccine that can be used more broadly than the vaccine presently available. A clinical development program has evaluated the long-term safety, immunogenicity, and vaccine efficacy (VE) of TAK-003, a live attenuated tetravalent dengue vaccine with a DENV-2 backbone engineered to elicit immune responses to all 4 dengue serotypes. nd dose, and for another 25 months after a booster dose. Data up to 3 years after the second vaccination are currently available.18 clinical trials in 13 countries have involved 28,175 seropositive/seronegative participants aged from 1.5-60 years from endemic/non-endemic regions. In the ongoing pivotal phase III study, 4–16-year-old healthy children  were randomized 2:1 to receive two doses of TAK-003 or placebo, 3 months apart for an evaluation of VE and safety over a multi-year period stratified pre-vaccination dengue serostatus. Active surveillance throughout the trial detected symptomatic dengue. The trial will continue up to 4–4.5 years post 2nd dose. At 18 months, VE was 66.2% (95% CI: 49.1–77.5) in dengue-naive and 76.1% (95% CI: 68.5–81.9) in dengue pre-exposed participants, with VE of 90.4% (95% CI: 82.6–94.7) and 85.9% (95% CI: 31.9–97.1) for prevention of hospitalized VCD and dengue hemorrhagic fever, respectively. Cumulative VE against VCD from first dose to 3 years post 2nd dose was 62.0% (95% CI: 56.6–66.7) and 83.6% (95% CI: 76.8–88.4) in prevention of hospitalized VCD. Some decline in VE was observed over time mainly driven by outpatient dengue. Two doses of TAK-003 3 months apart were well-tolerated with no important safety risks identified up to 3 years after completion of the vaccination schedule. Safety and immunogenicity data from Phase I/II studies established the final formulation and dosing schedule. Overall VE in the pivotal phase III study was 80.2% [95% CI: 73.3–85.3] against virologically confirmed dengue (VCD) at 12 months post 2TAK-003 is immunogenic against all 4 dengue serotypes and continues to be efficacious, well-tolerated, and with no evidence of disease enhancement in seronegative population up to 3 years post-vaccination.Vianney Tricou, D Phil, Takeda Pharmaceuticals International (Employee) Shibadas Biswal, MD, Takeda Vaccines, Inc (Employee) Sanjay S. Patel, PhD, Takeda Pharmaceuticals International AG (Employee) Olaf Zent, MD, Takeda Pharmaceuticals International AG (Employee) Martina Rauscher, PhD, Takeda Pharmaceuticals International AG (Employee) Gonzalo Perez, MD, Takeda group companies (Employee) Walid Kandeil, MD, Takeda Pharmaceuticals International AG (Employee) Nicolas Folschweiller, PhD, Takeda (Employee)


KBP-7072 was active against Staphylococcus aureus , methicillin-resistant S. aureus , S. lugdunensis , and other coagulase-negative staphylococci . KBP-7072 was active against Enterococcus faecalis  and vancomycin-susceptible and -nonsusceptible E. faecium ; Streptococcus pneumoniae , including penicillin- and tetracycline-resistant strains; S. agalactiae , including macrolide-resistant strains; S. pyogenes ; and viridans group streptococci, including S. anginosus group  isolates. KBP-7072 inhibited 90.2%  of all Enterobacterales isolates, including expanded-spectrum β-lactamase-phenotype strains at ≤2 mg/liter. KBP-7072 demonstrated potent activity against Acinetobacter baumannii-calcoaceticus species complex and Stenotrophomonas maltophilia isolates , Haemophilus influenzae , and Moraxella catarrhalis . Based on MIC90 values, KBP-7072 in vitro activity was generally superior to that the other tetracycline class comparators tested. The potent activity of KBP-7072, including resistant organism groups, merits further clinical investigation in infections where these organisms are likely to occur.KBP-7072 is a novel broad-spectrum tetracycline (aminomethylcycline) antibacterial in clinical development  for the treatment of acute bacterial skin and skin structure infections, community-acquired bacterial pneumonia, and complicated intra-abdominal infections. KBP-7072 is active against many of the World Health Organization priority pathogens. In this study, KBP-7072 and tetracycline class comparators were susceptibility tested against 1,057 geographically diverse surveillance isolates from 2019 according to Clinical and Laboratory Standards Institute (CLSI) guidelines. KBP-7072 demonstrated potent  The effectiveness of tetracycline antibacterials has declined since their initial discovery and introduction in the late 1940s, primarily due to the emergence of resistance caused by efflux and ribosomal protection mechanisms . This re1–5–KBP-7072  has comp10–in vitro antibacterial activity against many of the organisms listed on the World Health Organization (WHO) priority pathogen list, including methicillin-resistant Staphylococcus aureus, penicillin-nonsusceptible Streptococcus pneumoniae, vancomycin-resistant Enterococcus faecium, ampicillin-resistant Haemophilus influenzae, and carbapenem-resistant Acinetobacter baumannii , percent intermediate (I), and percent resistant (R) according to CLSI or FDA breakpoint interpretive criteria, are presented in 90 values, KBP-7072 was the most active agent tested against S. aureus, including methicillin-resistant S. aureus (MRSA) , tetracycline-resistant S. aureus , and enterococci , including vancomycin-nonsusceptible strains , S. agalactiae , S. pyogenes , and S. pneumoniae , including penicillin-resistant, tetracycline-resistant, and macrolide-resistant strains at ≤0.12 mg/liter  was comparable in activity to tigecycline , 8-fold more active than omadacycline and minocycline , 16-fold more active than doxycycline , and >32-fold more active than tetracycline   was 4-fold more active than tigecycline , 8-fold more active than omadacycline and minocycline , >32-fold more active than doxycycline , and >64-fold more active than tetracycline  (H. influenzae isolates (100.0%) were inhibited by ≤0.25 mg/liter KBP-7072 (Cumulative percent inhibition and MIC strains  and 2. Kmg/liter . Againstg/liter) . When teg/liter) . All H. KBP-7072 .50/90, 0.06/0.12 mg/liter; 100.0% inhibited at ≤0.5 mg/liter) demonstrated potent in vitro activity against 104 S. aureus isolates, including methicillin-susceptible S. aureus (MSSA)  and MRSA  organism subsets  was 2-fold more active than minocycline , omadacycline , and tigecycline , 8-fold more active than doxycycline , and 128-fold more active than tetracycline  (KBP-7072 (MIC subsets  and 2. Sas 11.5% . Based oeptible) .50/90, 0.03/0.03 mg/liter; 100.0% inhibited at ≤0.03 mg/liter) demonstrated potent in vitro activity against 20 Staphylococcus lugdunensis isolates where resistance to tetracycline was 5.0%  was comparable in activity to minocycline , 2-fold more active than doxycycline , omadacycline , and tigecycline  and 4-fold more active than tetracycline  (KBP-7072 (MICwas 5.0% . Based oeptible)  and 2.50/90, 0.06/0.25 mg/liter, 100% inhibited at ≤0.5 mg/liter) and tigecycline  were comparable in activity against 22 other coagulase-negative staphylococci (CoNS) isolates  was 2-fold more active than minocycline , 4-fold more active than omadacycline , 32-fold more active than doxycycline , and 256-fold more active than tetracycline  against other CoNS isolates  isolates  was 2-fold more active than omadacycline and tigecycline  , minocycline , and tetracycline  demonstrated limited activity against E. faecalis isolates (KBP-7072 was highly active against 51 isolates . Based oeptible) . Doxycycisolates .E. faecium  isolates, and its activity was not adversely affected by susceptibility or nonsusceptibility to vancomycin  was 2-fold more active than tigecycline  and 4-fold more active than omadacycline  , minocycline , and tetracycline  demonstrated reduced activity against E. faecium isolates  . Doxycycisolates .S. pneumoniae isolates (n = 127) were highly susceptible to KBP-7072 , and its activity was not adversely affected by resistance to erythromycin , penicillin , or tetracycline   was comparable in activity to tigecycline , 2-fold more active than omadacycline , 256-fold more active than doxycycline  and minocycline , and 2,048-fold more active than tetracycline  , and 27.6%, respectively , 22.0% for clindamycin, and 18.1% for trimethoprim-sulfamethoxazole (data not shown).g/liter)  and 2. Beptible) . Resistaectively . ResistaS. agalactiae  and 51 S. pyogenes isolates , were inhibited by ≤0.06 mg/liter of KBP-7072 regardless of erythromycin (macrolide) resistance  was comparable in activity to tigecycline , 4-fold more active than omadacycline , 256-fold more active than doxycycline , 512-fold more active than minocycline , and 1,024-fold more active than tetracycline   was 2-fold more active than tigecycline , 4-fold more active than omadacycline , 256-fold more active than doxycycline and minocycline , and 1,024-fold more active than tetracycline   . Similareptible) .Streptococcus anginosus group isolates (n = 17) were inhibited by low concentrations of KBP-7072  and tigecycline  , 256-fold more active than doxycycline (MIC90 8 mg/liter), 512-fold more active than minocycline , and 1,024-fold more active than tetracycline  .All eptible) . Based oeptible) . Resista50/90, 0.25/2 mg/liter; 90.2% inhibited at ≤2 mg/liter) and tigecycline  were the most active tetracycline class compounds tested against 410 Enterobacterales isolates  was 8-fold more active than omadacycline  and minocycline , 16-fold more active than doxycycline , and >32-fold more active than tetracycline  against Enterobacterales isolates  was comparable in activity to tigecycline against 133 tetracycline-resistant Enterobacterales isolates  and meropenem  (data not shown).KBP-7072  and tigecycline  were the most active tetracycline class agents tested against 22 Citrobacter freundii species complex isolates  was 8-fold more active than omadacycline  and 16-fold more active than doxycycline, minocycline, and tetracycline  (KBP-7072 (MICisolates . Based oeptible) .Citrobacter koseri isolates (n = 21) were susceptible (100.0%) to doxycycline, minocycline, tetracycline, and tigecycline. KBP-7072 and tigecycline were the most active tetracycline class agents against C. koseri, with MIC90 values of 0.25 mg/liter.All 90, 0.5 mg/liter; 100.0% inhibited at ≤4 mg/liter) and tigecycline  were the most active tetracycline class agents tested against 50 Enterobacter cloacae species complex isolates  was 4-fold more active than doxycycline  and 8-fold more active than minocycline , omadacycline , and tetracycline   was equally active against ceftazidime-susceptible and ceftazidime-nonsusceptible (AmpC-derepressed phenotype) E. cloacae species complex isolates (KBP-7072 (MICisolates  and 3. Beptible) . KBP-707isolates  and 3.50/90, 0.12/0.5 mg/liter; 100.0% inhibited at ≤2 mg/liter) was active against 77 Escherichia coli isolates, including a subset of 26 expanded-spectrum β-lactamase (ESBL)-phenotype E. coli isolates   was comparable in activity to tigecycline , 4-fold more active than omadacycline , 8-fold more active than minocycline , 32-fold more active than doxycycline , and >64-fold more active than tetracycline  (KBP-7072 (MICg/liter)  and 3. Aeptible) .90, 0.5 mg/liter; 100.0% inhibited at ≤4 mg/liter) and tigecycline  were the most active tetracycline class agents tested against 21 Klebsiella aerogenes isolates  was 4-fold more active than minocycline  and omadacycline , 8-fold more active than doxycycline , and 16-fold more active than tetracycline  (KBP-7072 (MICisolates . Based oeptible) .90, 0.5 mg/liter; 100.0% inhibited at ≤2 mg/liter) and tigecycline  were comparable in activity against 53 K. oxytoca isolates  was 4-fold more active than omadacycline , 8-fold more active than minocycline , and 16-fold more active than doxycycline and tetracycline  (KBP-7072 (MICisolates . Based oeptible) .50/90, 0.25/1 mg/liter; 100.0% inhibited at ≤4 mg/liter) was active against 80 K. pneumoniae isolates, including a subset of 27 ESBL-phenotype K. pneumoniae isolates   was comparable in activity to tigecycline , 8-fold more active than omadacycline , 16-fold more active than doxycycline , >16-fold more active than minocycline , and >32-fold more active than tetracycline  (KBP-7072 (MICg/liter)  and 3. Aeptible) .50/90, 1/2 mg/liter; 95.0% inhibited at ≤2 mg/liter) and tigecycline  were the most active tetracycline class agents tested against 20 Morganella morganii isolates , minocycline , doxycycline , and tetracycline  (KBP-7072 (MICisolates  and 3. Reptible) .Proteus mirabilis isolates, including KBP-7072 , doxycycline , minocycline , omadacycline , tetracycline , and tigecycline  (All tetracycline class agents demonstrated reduced or limited activity against 22 eptible)  and 3.90, 4 mg/liter; 95.5% inhibited at ≤4 mg/liter) and tigecycline  were the most active tetracycline class agents tested against 22 Providencia species isolates , minocycline , omadacycline , and tetracycline  (KBP-7072 (MICisolates  and 3. Oeptible) .90, 1 mg/liter; 95.5% inhibited at ≤1 mg/liter) and tigecycline  were the most active tetracycline class agents tested against 22 Serratia marcescens isolates  was 4-fold more active than minocycline , 8-fold more active than omadacycline , 16-fold more active than doxycycline , and >64-fold more active than tetracycline  (KBP-7072 (MICisolates  and 3. Beptible) .in vitro activity, KBP-7072  was the most potent tetracycline class agent tested against 22 A. baumanniicalcoaceticus species complex isolates  was 4-fold more active than tigecycline , 8-fold more active than minocycline  and omadacycline , >32-fold more active than doxycycline , and >64-fold more active than tetracycline  .Based on isolates . KBP-707eptible) . Compara50/90, 8/16 mg/liter) and all tetracycline class agents was limited against 22 Pseudomonas aeruginosa isolates  and minocycline  demonstrated potent in vitro activity against 22 Stenotrophomonas maltophilia isolates  was 2-fold more active than tigecycline , 8-fold more active than omadacycline , and 64-fold more active than tetracycline .KBP-7072 , doxycycline , minocycline , omadacycline , tetracycline , and tigecycline  (All tetracycline class agents were very active against 52 eptible) .50/90, 0.25/0.5 mg/liter; 100.0% inhibited at ≤0.5 mg/liter) was active against 12 H. parainfluenzae isolates  was comparable in activity to tigecycline , 2-fold more active than tetracycline , and 4-fold more active than doxycycline , minocycline , and omadacycline  (KBP-7072 (MICisolates  and 3. Beptible) .50/90, 0.06/0.06 mg/liter; 100.0% inhibited at ≤0.06 mg/liter), were active against 21 Moraxella catarrhalis isolates  pathogens, vancomycin-resistant E. faecium and MRSA were identified as priority 2 (high) pathogens, and ampicillin-resistant H. influenzae and penicillin-nonsusceptible S. pneumoniae were identified as priority 3 (medium) pathogens  at a dose level of 200 mg. The therapeutic dose for KBP-7072 is projected to be lower than the current daily oral dose for another aminomethylcycline class antibacterial (omadacycline) in community-acquired bacterial pneumonia and acute bacterial skin and skin structure infection ; tetracycline-resistant S. aureus (8-fold); E. faecium (4-fold); S. pneumoniae (2-fold), including penicillin-nonsusceptible strains; beta-hemolytic streptococci (4-fold); Enterobacterales (8-fold), including ESBL-phenotype and tetracycline-resistant strains; A. baumannii (8-fold); S. maltophilia (8-fold); and H. influenzae (4-fold).KBP-7072 has demonstrated dose-proportional pharmacokinetic/pharmacodynamic (PK/PD) properties in both animal models and phase I clinical studies supporting once-daily oral or intravenous administration 1013, 18–2018–nfection . A lowerin vitro activity of KBP-7072 was unaffected by isolates displaying resistance to tetracycline. KBP-7072 remained active against isolates displaying resistance to other antibacterial agents, including ampicillin, ceftazidime, erythromycin, penicillin, and vancomycin.The in vitro activity of KBP-7072 against A. baumannii is also supported by a prior study using 531 isolates that included carbapenem-resistant, colistin-resistant, ESBL-positive, metallo-β-lactamase-producing, and tetracycline-resistant strains  were collected from 117 medical centers located in 35 countries, including the United States , Europe , Latin America , and the Asia-Pacific region  as part of the SENTRY Surveillance Program. The surveillance isolates utilized in this study were randomly selected from patients with skin and skin structure infections , pneumonia in hospitalized patients , and community-acquired respiratory tract infections  and included only 1 isolate/patient/infection episode. The percentage of tetracycline-resistant isolates in this study generally mimicked the 2019 worldwide SENTRY Surveillance Program distributions for A. baumannii (54.5% versus 60.3% in SENTRY), Enterobacterales (32.4% versus 34.6% in SENTRY), H. influenzae (1.9% versus 1.4% in SENTRY), S. aureus (11.5% versus 6.0% in SENTRY), S. agalactiae (80.8% versus 79.6% in SENTRY), S. pneumoniae (27.6% versus 24.7% in SENTRY), and S. pyogenes (19.6% versus 21.2% in SENTRY). Organism identifications were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy .Geographically diverse, recent (2019) bacterial clinical isolates (KBP-7072 and omadacycline (KBP-3039) powders were supplied by KBP Biosciences Co., Ltd. . Doxycycline, tetracycline, and tigecycline powders were obtained from the United States Pharmacopeial Convention . Minocycline powder was obtained from Sigma-Aldrich .E. coli and K. pneumoniae isolates, MRSA, vancomycin-susceptible and -nonsusceptible E. faecium, penicillin-susceptible, -intermediate, -resistant , and tetracycline-resistant S. pneumoniae, erythromycin (macrolide)-resistant S. agalactiae and S. pyogenes, ceftazidime-susceptible and -nonsusceptible E. cloacae, carbapenem (meropenem)-resistant A. baumannii, and ampicillin-resistant H. influenzae  phenotype for fluenzae . Most ESanalysis .Broth microdilution susceptibility testing was conducted at JMI Laboratories according to Clinical and Laboratory Standards Institute M07  and M100E. faecalis ATCC 29212, E. coli ATCC 25922, E. coli ATCC 35218, P. aeruginosa ATCC 27853, and S. aureus ATCC 29213. All (100.0%) of the doxycycline (18/18), minocycline (15/15), omadacycline (18/18), tetracycline (25/25), and tigecycline (18/18) MIC values obtained were within CLSI-approved quality control ranges (JMI Laboratories followed current CLSI quality assurance practices when performing susceptibility tests. MIC values were validated by concurrently testing the CLSI-recommended  American


Scientific Reports 10.1038/s41598-021-84500-6, published online 23 March 2021Correction to: The original version of this Article contained errors in References 27, 43 and 44, where hyperlinks to external data were omitted and as a result were incorrectly given as:27. Kramarenko, A. V. Demo of non-contac polatimetric cardiograph testing, 43. Kramarenko, A. V. Demo of an industrial application (pump work control) of a non-contact rf registration device .44. Kramarenko, A. V. Demo of a car driver monitoring system .The correct references are listed below:https://www.youtube.com/watch?v=gOGvGjJ2QnI (Accessed 23 Jul 2020a).27. Kramarenko, A. V. Demo of non-contac polatimetric cardiograph testing, https://www.youtube.com/watch?v=z-1pzf3iUyM (Accessed 3 Nov 2020b).43. Kramarenko, A. V. Demo of an industrial application (pump work control) of a non-contact rf registration device, https://www.youtube.com/watch?v=yB9uKd3MNxU (Accessed 13 Oct 2020c).44. Kramarenko, A. V. Demo of a car driver monitoring system, The original Article has been corrected.


TB meningitis is the most severe form of tuberculosis (TB), associated with high morbidity and mortality. High-dose rifampin (35mg/kg/day) is safe in adults and substantially improves the bactericidal activity of standard TB regimen. However, there is conflicting data regarding its benefit in TB meningitis where outcomes may also be associated with intracerebral inflammatory responses. Mycobacterium tuberculosis infections were used for these studies . Animals received high-dose (35 mg/kg/day) or standard-dose (10 mg/kg/day) rifampin in combination with isoniazid, pyrazinamide and dexamethasone at human equipotent dosing. Bacterial burden, multi-modality positron emission tomography (PET) imaging, tissue drug concentrations, markers of neuroinflammation, and vascular leak were measured. Imaging data from a patient with TB meningitis was analyzed and correlated with the findings in animals.A novel mouse and a validated rabbit model of TB meningitis utilizing intracranial Figure 1. Mouse model of TB meningitis replicates human histopathology hallmarks. (A) Scheme of infection. (B) Histopathology hematoxylin-eosin (H&E) and acid-fast bacilli (AFB) staining in a representative M. tuberculosis-infected mouse shows regions of meningitis, ventriculitis, choroiditis, necrotizing and non-necrotizing granulomas. The bar represents 100µm. (C) Images show immunofluorescence of microglia activation in red (Iba-1) and nuclear stain in blue (DAPI). The rabbit model of TB meningitis has been described previously . Animal studies were approved by the Johns Hopkins Animal Care and Use Committee.P < 0.01) . There were no differences in intracerebral microglial activation (124I-DPA-713 PET and iDISCO) and pro-inflammatory cytokines during treatment in animals receiving high- or standard-dose rifampin regimens . Whole-brain PET and immunolabeling demonstrated spatially compartmentalized inflammation, vascular leak and rifampin exposures . Longitudinal imaging in the same animals showed a 40% decrease in vascular leak after two weeks of TB treatment. Spatially compartmentalized brain rifampin exposures and decreases in vascular edema over TB treatment were also noted in the TB meningitis patient.Administration of the high-dose rifampin regimen achieved four times higher brain concentration than the standard-dose regimen and displayed higher bactericidal activity in both mice and rabbits  Experimental scheme. R10 (rifampin 10mg/kg), R35 (rifampin 35mg/kg), H (isoniazid), Z (pyrazinamide), D (dexamethasone). (B) Bactericidal activity of high-dose rifampin  and standard-dose rifampin  regimens in mice. (C) Grouped colony forming units (CFU) and (D) rifampin brain concentration in mice after 42 days of TB treatments. (E) Bactericidal activity of high-dose rifampin  and standard-dose rifampin  regimens in rabbits. Data from untreated rabbits  is also shown. (F) Grouped CFU and (G) rifampin brain concentration in rabbits after 14 days of TB treatments. Tissues were assayed using validated ultra-high-performance liquid chromatography and tandem mass spectrometry (LC-MS/MS) for rifampin at the Infectious Diseases Pharmacokinetics Laboratory of the University of Florida. The bacterial burden is represented as CFU per gram of tissue and presented on a logarithmic scale. CFU and mass spectrometry data are represented as mean ± SD. *P < 0.05, **P < 0.01 and ***P < 0.001 calculated using a two-way ANOVA test.Figure 3. Neuroinflammatory responses during TB treatment. (A) Iba-1 and DAPI immunofluorescence in a representative untreated, high-dose and low-dose-treated mouse. (B) Quantification of Iba-1 immunofluorescence before treatment and after 6 weeks of treatment (n = 3 mice per group). Sections were imaged at 40X with Nikon A1+ confocal microscope. HALO was used for visualization and quantification. Quantification of intraparenchymal (C) INF-γ, (D) TNF and (E) MCP-1 in untreated and treated mice (Milliplex Multiplex Luminex assay). (F) Coronal CT and 124I-DPA-713 PET/CT of a representative mouse with TB meningitis before treatment initiation. (G) 124I-DPA-713 PET quantification before treatment  and after 2  and 6  weeks of TB treatment. PET data is represented as median ± IQ. *P < 0.05, **P < 0.01 and ***P < 0.001 were calculated using a two-way ANOVA test.Figure 4. Changes in vascular leakage and rifampin penetration during TB treatment. (A) Experimental scheme in mice. (B) Whole-brain immunolabeling (iDISCO) of a representative M. tuberculosis-infected mouse prior to treatment initiation. Images show immunolabeling of α-smooth muscle actin in grey and microglia activation in red (Iba-1). Asterix represents the areas of vascular amputation. (C) Coronal 18F-py-Albumin PET/CT and quantification (tissue to plasma ratio) in untreated and 2 weeks-treated mice . (D) Serial imaging in a patient with TB meningitis. (E) Transverse T2 post-contrast section and maximal intensity projection (MIP) showing vasogenic edema. (F) Co-registered T2 post-contrast MIP with transverse 11C-rifampin area under the curve (AUC) heat-map, and 11C-rifampin tissue to plasma ratio quantification of the areas with and without vasogenic edema, and unaffected brain. (G) T2 post-contrast MIP at 3 and 45 months after treatment initiation. The patient with TB meningitis was recruited as part of a 11C-rifampin PET research study performed under the U.S. FDA Radioactive Drug Research Committee program for investigational drugs . Human studies were approved by the Johns Hopkins University Institutional Review Board Committee. M = moxifloxacin. PET data is represented as median ± IQ. *P < 0.05, **P < 0.01 and ***P < 0.001 calculated using a two-way ANOVA test.Our cross-species findings suggest that an intensified high-dose rifampin regimen is more efficacious than the standard treatment for TB meningitis without an increase in neuroinflammation. Vascular leak decreases during TB treatment and may account for decreases in rifampin permeability over time. These studies have important implications for antimicrobial development for TB meningitis.Charles A. Peloquin, Pharm.D., Nothing to disclose Alvaro A. Ordonez, MD, Cubresa (Consultant)Fujirebio Diagnostics (Research Grant or Support) Sanjay K. Jain, MD, Fujirebio Diagnostics, Inc., USA (Research Grant or Support)Novobiotic LLC, USA (Research Grant or Support)T3 Pharma, Switzerland (Research Grant or Support) Sanjay K. Jain, MD, Fujirebio Diagnostics, Inc., USA  Involved: Self): Research Grant or Support; Novobiotic LLC, USA  Involved: Self): Research Grant or Support; T3 Pharma, Switzerland  Involved: Self): Research Grant or Support


CLSI broth microdilution was used to determine MICs for Enterobacterales , Pseudomonas aeruginosa , Acinetobacter baumannii complex , Stenotrophomonas maltophilia , and Burkholderia cepacia complex (n = 425). MICs were interpreted by CLSI-approved clinical breakpoints (February 2021). Cefiderocol inhibited 99.8, 96.7, 91.6, and 97.7% of all Enterobacterales, meropenem-nonsusceptible, ceftazidime-avibactam-nonsusceptible, and ceftolozane-tazobactam-nonsusceptible isolates, respectively, at ≤4 μg/mL (susceptible breakpoint). Cefiderocol inhibited 99.9, 99.8, 100, and 99.8% of all P. aeruginosa, meropenem-nonsusceptible, ceftazidime-avibactam-nonsusceptible, and ceftolozane-tazobactam-nonsusceptible isolates, respectively, at ≤4 μg/mL (susceptible breakpoint). Cefiderocol inhibited 96.0% of all A. baumannii complex isolates and 94.2% of meropenem-nonsusceptible isolates at ≤4 μg/mL (susceptible breakpoint) and 98.6% of S. maltophilia isolates at ≤1 μg/mL (susceptible breakpoint). B. cepacia complex isolates were tested with a MIC50 of ≤0.03 μg/mL and MIC90 of 0.5 μg/mL. Annual cefiderocol percent susceptible rates for Enterobacterales  and P. aeruginosa  were unchanged from 2014 to 2019. Annual percent susceptible rates for A. baumannii complex demonstrated sporadic, nondirectional differences ; the wider range for Europe (∼7%) was due to isolates from Russia. Annual percent susceptible rates for S. maltophilia showed minor, nondirectional differences . We conclude that clinical isolates of Enterobacterales (99.8% susceptible), P. aeruginosa (99.9%), A. baumannii (96.0%), and S. maltophilia (98.6%) collected in North America and Europe from 2014 to 2019 were highly susceptible to cefiderocol.We report  Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii as pathogens of the highest  priority for development of new antibacterial agents  when limited or no other treatment options exist , P. aeruginosa, and Acinetobacter baumannii complex. Clinical development of cefiderocol continues for the treatment of serious infections attributable to resistant Gram-negative bacilli, including infections caused by carbapenem-resistant Gram-negative bacilli , and difficult-to-treat Gram-negative bacilli is increasing worldwide, and therapeutic options for infected patients are often limited –3. The W–l agents . Cefiderns exist . In Aprins exist . In Sept bacilli .Cefiderocol possesses a unique mechanism of bacterial cell entry, making it an important addition to the antimicrobial armamentarium. The optimized chloro-catechol moiety within the C-3 side chain of cefiderocol facilitates formation of chelated complexes with ferric iron and expedites its transport across the outer membrane of Gram-negative bacilli using constitutive iron transport systems . Followi7–in vitro activities for recently approved and investigational agents is critical to establishing and supporting treatment decisions and expanding the role of these agents in patient care, particularly for patients where unmet medical need exists , 8 μg/mL (intermediate), and ≥16 μg/mL (resistant) and for Stenotrophomonas maltophilia of ≤1 μg/mL (susceptible) and >1 μg/mL (nonsusceptible)  . The updeptible)  and the eptible)   collected over five consecutive annual SIDERO-WT surveillance studies (from November 2014 to December 2019) conducted in North America and Europe using the recently approved (February 2021) CLSI MIC clinical breakpoints  and 90% (MIC90) of the 31,896 isolates of Enterobacterales tested from North America and Europe from 2014 to 2019 were 0.12 and 1 μg/mL, respectively  isolates of Enterobacterales; 96.7% of meropenem-nonsusceptible isolates were susceptible to cefiderocol. Cefiderocol demonstrated a higher percent susceptible rate against meropenem-nonsusceptible isolates (≥20% higher) than ceftazidime-avibactam (77.0%), cefepime (8.7%), ceftolozane-tazobactam (7.8%), and ciprofloxacin (7.8%). A total of 91.6% of 263 isolates of ceftazidime-avibactam-nonsusceptible  Enterobacterales and 97.7% of 2,658 isolates of ceftolozane-tazobactam-nonsusceptible  Enterobacterales were susceptible to cefiderocol. In comparison, only 3.8% of ceftazidime-avibactam-nonsusceptible Enterobacterales isolates were susceptible to ceftolozane-tazobactam and 90.5% of ceftolozane-tazobactam-nonsusceptible Enterobacterales isolates were susceptible to ceftazidime-avibactam. MIC90 values for colistin  and ciprofloxacin were 1 and >8 μg/mL, respectively, for all isolates of Enterobacterales tested.The minimal inhibitory concentrations of cefiderocol that inhibited 50%  demonstrated a rightward shift (of 1 to 3 doubling dilutions) to higher cefiderocol MICs compared to each respective antimicrobial-susceptible subset; however, as mentioned earlier, most meropenem (96.7%)-, ceftazidime-avibactam (91.6%)-, and ceftolozane-tazobactam (97.7%)-nonsusceptible isolates remained susceptible to cefiderocol, with MICs of ≤4 μg/mL.Cefiderocol MICs for meropenem-nonsusceptible , ceftazi50 and MIC90 were 0.12 and 0.5 μg/mL for 7,700 isolates of P. aeruginosa collected in North America and Europe from 2014 to 2019  P. aeruginosa were 0.25 and 1 μg/mL, respectively, and 99.9% of meropenem-nonsusceptible isolates were susceptible to cefiderocol. Ceftazidime-avibactam, ceftolozane-tazobactam, and cefepime were all tested with MIC90 values of 32 or >64 μg/mL against isolates of meropenem-nonsusceptible P. aeruginosa and exhibited percent susceptible rates of 76.1% (ceftolozane-tazobactam), 75.0% (ceftazidime-avibactam), and 49.0% (cefepime). MIC90 values for ciprofloxacin (31.2% susceptible) and colistin were >8 μg/mL and 1 μg/mL, respectively, for meropenem-nonsusceptible P. aeruginosa. A total of 100% of 477 isolates of ceftazidime-avibactam-nonsusceptible  and 99.8% of 463 isolates of ceftolozane-tazobactam-nonsusceptible  P. aeruginosa, respectively, were susceptible to cefiderocol. In comparison, only 24.3% of ceftazidime-avibactam-nonsusceptible P. aeruginosa isolates were susceptible to ceftolozane-tazobactam, and only 22.0% of ceftolozane-tazobactam-nonsusceptible P. aeruginosa isolates were susceptible to ceftazidime-avibactam.The cefiderocol MIC to 2019 . CefiderP. aeruginosa (both North American and European isolates combined) demonstrated a rightward shift (of 1 doubling dilution) to higher cefiderocol MICs compared to each respective antimicrobial-susceptible subset; however, almost every nonsusceptible isolate (99.8 to 100%) remained susceptible to cefiderocol, with a MIC of ≤4 μg/mL.Cefiderocol MICs for meropenem-nonsusceptible , ceftazi50 and MIC90 of cefiderocol for isolates of A. baumannii complex from both North America and Europe were 0.12 and 1 μg/mL; 96.0% of isolates demonstrated cefiderocol MICs of ≤4 μg/mL  and MIC90 values (1 μg/mL) for the meropenem-nonsusceptible subset of isolates  and Europe (99.3 to 99.9% susceptible) varied over very narrow ranges (0.4 to 0.6%)  than for isolates from Europe (90.4 to 97.5%). In total, there were 171 isolates of A. baumannii with cefiderocol MICs of ≥8 μg/mL (nonsusceptible) collected in Europe from 2014 to 2019. Of these isolates, 74.3% (127/171) were from one country (Russia); 127/437 (29.1%) of isolates from Russia were cefiderocol nonsusceptible, with annual rates of 28.2% (11/39) in 2014, 41.2% (7/17) in 2015, 24.1% (19/79) in 2016, 42.7% (50/117) in 2017, 31.9% (36/113) in 2018, and 5.6% (4/72) in 2019. Other European countries contributing >10 isolates over the study period submitted isolates with cefiderocol-nonsusceptible MICs at rates ranging from zero (no cefiderocol-nonsusceptible isolates) to 7.3% (8/109 isolates [United Kingdom]). Annual cefiderocol MIC distributions for Enterobacterales, P. aeruginosa, A. baumannii complex, S. maltophilia, and B. cepacia complex are provided in Tables S2 to S6 in the supplemental material.Annual cefiderocol percent susceptible rates for isolates of to 0.6%) . Even leEnterobacterales from North America (99.7 to 100%) and Europe (98.2 to 98.8%) were similar , while annual percent susceptible rates for ceftolozane-tazobactam were higher in isolates from North America (93.8 to 94.9%) than in those from Europe (87.3 to 90.6%) (P. aeruginosa from North America were higher for both ceftazidime-avibactam (96.0 to 99.6%) and ceftolozane-tazobactam (96.7 to 99.6%) than for isolates from Europe .Annual percent susceptible rates for ceftazidime-avibactam for isolates of o 90.6%) . Annual Enterobacterales, P. aeruginosa, A. baumannii complex, S. maltophilia, and B. cepacia complex collected in 2019 were also tested against meropenem-vaborbactam and imipenem-relebactam . Meropenem-vaborbactam demonstrated in vitro activity similar to that of ceftazidime-avibactam against Enterobacterales (98.9% of isolates susceptible); <70% of meropenem-nonsusceptible Enterobacterales isolates were susceptible to meropenem-vaborbactam and imipenem-relebactam, compared to 93.2% susceptible for cefiderocol. Imipenem-relebactam was less active (83.9% susceptible) than ceftazidime-avibactam against P. aeruginosa, compared to 99.9% susceptible for cefiderocol. Meropenem-vaborbactam and imipenem-relebactam were largely inactive in vitro against clinical isolates of A. baumannii complex  and S. maltophilia .Isolates of Enterobacterales (99.8%), P. aeruginosa (99.9%), A. baumannii complex (96.0%), and S. maltophilia (98.6%) collected across North America and Europe from 2104 to 2019 were susceptible to cefiderocol. Data in the current study confirm and expand upon data presented in earlier studies. Cefiderocol was previously reported to demonstrate potent in vitro activity against key Gram-negative pathogens  but only limited activity against Gram-positive and anaerobic bacteria , P. aeruginosa (≥97%), and A. baumannii complex (≥91%) isolates, as well as MDR Enterobacterales (≥97%), P. aeruginosa (≥97%), and A. baumannii complex (≥90%) isolates  and P. aeruginosa (>99%), with ceftazidime-avibactam-, ceftolozane-tazobactam-, cefepime-, ciprofloxacin- and colistin-resistant phenotypes at MICs of ≤4 μg/mL , S. maltophilia , and B. cepacia complex .Data in the current study clearly demonstrate that the large majority of isolates of bacteria , 10, 15.cteria 2023 and rerales 99.%, P. aercteria 20–14, 24 hrales 99.%, P. aerrales 99.%, P. aerEnterobacterales, P. aeruginosa, and A. baumannii have not been identified, although the addition of avibactam, a β-lactamase inhibitor, to cefiderocol has been shown to lower the MICs for some cefiderocol-resistant isolates, primarily A. baumannii possessing various ESBLs.  or PiuA (not PirA) (P. aeruginosa) can also elevate cefiderocol MICs  or Acinetobacter spp. , and the FDA has not published breakpoints for S. maltophilia , P. aeruginosa (99.9%), A. baumannii complex (96.0%), and S. maltophilia (98.6%) in North America and Europe are susceptible to cefiderocol by the recently approved CLSI MIC breakpoints  and P. aeruginosa  were negligible. Annual percent susceptible rates for A. baumannii complex demonstrated sporadic, nondirectional differences , primarily due to isolates from Russia. Annual percent susceptible rates for S. maltophilia also showed minor, nondirectional fluctuation . In vitro susceptibility testing of cefiderocol may be of benefit when cefiderocol is being considered for treatment of patients infected with carbapenem-nonsusceptible, ceftazidime-avibactam-nonsusceptible, or ceftolozane-tazobactam-nonsusceptible isolates of Enterobacterales and P. aeruginosa, carbapenem-nonsusceptible isolates of A. baumannii complex, and MDR isolates of S. maltophilia.We conclude that most current (2014 to 2019) clinical isolates of akpoints . ImportaEnterobacterales, 7,700 isolates of P. aeruginosa, 5,225 isolates of A. baumannii complex, 2,030 isolates of S. maltophilia, and 425 isolates of B. cepacia complex were collected in North America and Europe from 2014 to 2019. All isolates were shipped to IHMA , where their identities were confirmed using matrix-assisted laser desorption ionization–time of flight mass (MALDI-TOF) mass spectrometry .SIDERO-WT surveillance studies, sponsored by Shionogi & Co., Ltd., , were run annually from November 2014 to December 2019. In those studies, predefined quotas of isolates of specific Gram-negative bacilli cultured from patients with intra-abdominal, urinary tract, lower respiratory tract, skin and soft tissue, or bloodstream infections were collected from clinical laboratories in North America and Europe as previously described , 15, 20.Enterobacterales, P. aeruginosa, and Acinetobacter species of ≤4 μg/mL for susceptible, 8 μg/mL for intermediate, and ≥16 μg/mL for resistant and MIC breakpoints for S. maltophilia of ≤1 μg/mL for susceptible and >1 μg/mL for nonsusceptible (CLSI-defined broth microdilution susceptibility testing was performed at IHMA using custom in-house-prepared broth microdilution panels , 16, 30.ceptible .


DRIVE-FORWARD is a phase 3 trial with a completed double-blind period comparing doravirine (DOR) 100 mg with ritonavir-boosted darunavir (DRV/r) 800/100 mg, both administered with two nucleos(t)ide reverse transcriptase inhibitors , and an ongoing open-label extension. At Week (W) 48, DOR demonstrated non-inferior efficacy to DRV/r, with a superior lipid profile. Those results were sustained at W96. Here we present efficacy and safety results through W192.Participants who completed the 96-week double-blind phase and met inclusion criteria were eligible to receive open-label DOR plus two NRTIs in a 96-week extension. Efficacy and safety at W192 were assessed in two groups: participants initially randomized to DOR and maintained on DOR (n=259) and those who switched from DRV/r to DOR at W96 (n=233).3) and those switched from DRV/r (53 cells/mm3). Protocol-defined virologic failure occurred in 3.1% and 5.6% of participants maintained on DOR and switched from DRV/r, respectively, and development of genotypic resistance was low in both groups (Table 1). Discontinuation due to adverse events was also low (Table 1). Fasting LDL-cholesterol, non-HDL-cholesterol, and triglycerides showed minimal increase in participants maintained on DOR and were reduced in those switched from DRV/r to DOR (Table 1). Participants maintained on DOR had minimal weight gain after W96 (median 1 kg), and a small increase overall ; participants who switched to DOR had a small increase after W96 (median 1.5 kg), similar to the median weight gain in the base study .HIV-1 RNA < 50 copies/mL were maintained through W192 in 81.1% of participants who continued DOR and 80.7% of those who switched from DRV/r to DOR. The mean increase in CD4 T-cell counts from W96 to W192 was similar for participants maintained on DOR ViiV Healthcare  Kathleen Squires, MD, Merck (Employee) Sushma Kumar, PhD, Merck (Employee) Hong Wan, PhD, Merck (Employee) Valerie Teal, MS, Merck (Employee) Ernest Asante-Appiah, PhD, Merck (Employee) Peter Sklar, MD, Merck (Employee) Elizabeth A. Martin, DO, MPH, MBA, Merck (Employee) Rima Lahoulou, n/a, Merck (Employee)


African Americans (AA) and Latinos, compared with Whites, experience disproportionately higher rates of morbidity and mortality in COVID-19. Exuberant inflammatory responses may explain, in part, the differences in disease severity in COVID-19 observed among different demographic groups.In a retrospective cohort study, we analyzed data from patients aged ≥18 years hospitalized for COVID-19 (confirmed by positive SARS-CoV-2 PCR) from 3/1/2020 – 12/31/2020 at Emory Healthcare hospitals. Patient demographics, clinical characteristics, and peak levels of high-sensitivity C-reactive protein (hs-CRP) during hospitalization were abstracted from electronic medical record. Comorbidity burden was defined as the number of six total comorbidities assessed per patient. Multivariable logistic regression  assessed the effects of race and comorbidity burden on peak hs-CRP level.3,860 patients, median age 60 [18-108] years, 51% female, 57% AA, 28% White, 6% Latino and 9% other races were enrolled. Median comorbidity burden per patient was 2 , with prevalent comorbidities distributed as follows: 68% had hypertension, 43% renal disease, 42% diabetes, 16% cardiovascular disease, 12% lung disease, and 5% cancer. Unadjusted peak hs-CRP (mg/L) levels were highest among Latino patients (144.9) followed by other races (137), AA (130.3), and Whites (122.2). In adjusted models (including race), the mean difference in peak hs-CRP (mg/L) compared with patients who had no comorbidities was 18.7 (p=0.108), 56.7 (p< 0.001), and 78.2 mg/L (p< 0.001) for 1, 2, and ≥3 comorbidities, respectively. In adjusted models (including comorbidity burden), the mean level of peak hs-CRP, compared with Whites, was 34.2 (p< 0.001), 38.4 (p=0.003), and 36.0 mg/L (p=0.06) higher in AA, Latinos, and other races, respectively.Among patients hospitalized with COVID-19, non-White race and comorbidity burden were associated with significantly higher levels of inflammation. These findings suggest that exuberant inflammatory responses may be driving, in part, the differences in COVID-19 disease severity observed across different demographic groups. Lauren F. Collins, MD, MSc, Nothing to disclose


Ceftolozane/tazobactam (C/T) is an antipseudomonal cephalosporin combined with a β-lactamase inhibitor approved by FDA and EMA for complicated urinary tract (cUTI) and complicated intraabdominal infections (cIAI), as well as hospital-acquired/ventilator-associated bacterial pneumonia (HABP/VABP) in patients ≥18 years. Clinical trials studying the use of C/T for pediatric patients with cUTI and cIAI are completed, and HABP/VABP pediatric studies are underway. We evaluated the antimicrobial activity of C/T against gram-negative isolates collected from patients ≤17 years in the United States (US) as part of the global SMART surveillance program.P. aeruginosa were screened for genes encoding β-lactamases.In 2017-2019, 27 US clinical labs each collected up to 250 consecutive gram-negative pathogens per year. A total of 1336 isolates were collected from pediatric patients. MICs were determined using CLSI broth microdilution and breakpoints. C/T-nonsusceptible Enterobacterales (Ebact) and P. aeruginosa isolates, 40.7% and 76.4%, respectively, were collected from patients with respiratory tract infections, 37.0% and 10.0% from UTI, 13.7% and 8.2% from IAI, and 8.3% and 5.0% from bloodstream infections. The table shows antimicrobial susceptibility of Ebact, P. aeruginosa, and select phenotypes. C/T was active against 98% of Ebact, including 50 of 51 and 12 of 13 ESBL-non-CRE phenotype E. coli and K. pneumoniae, respectively. Among P. aeruginosa, C/T was active against 95% of isolates, 9-21 percentage points higher than the comparator β-lactams, and it maintained activity against 71-75% of P. aeruginosa isolates nonsusceptible to commonly used β-lactams. Among the 21 C/T-nonsusceptible Ebact, 2 isolates carried KPC and ESBL and 3 isolates carried only ESBL; in 16 isolates no β-lactamases were detected, of which 15 were species with intrinsic AmpC. Among 12 C/T-nonsusceptible P. aeruginosa, no acquired β-lactamases were detected, likely indicating chromosomally-mediated resistance mechanisms.Among the 944 collected Ebact and 220 Results TableP. aeruginosa, including resistant phenotypes.C/T could be a potential new treatment option for US pediatric patients with infections caused by Ebact and Sibylle Lob, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor) Meredith Hackel, PhD MPH, IHMA (Employee)Pfizer, Inc. (Independent Contractor) C. Andrew DeRyke, PharmD, Merck & Co., Inc.  Kelly Harris, PharmD, BCPS, Merck & Co. Inc (Employee) Katherine Young, MS, Merck (Employee) Mary Motyl, PhD, Merck & Co., Inc.  Daniel F. Sahm, PhD, IHMA (Employee)Pfizer, Inc. (Independent Contractor)


Dear Editors,We and others have shown that kidney transplant recipients (KTR) exhibit a reduced immune response with a seroconversion (SC) rate <50% after a regular 2-dose mRNA SARS-CoV-2 vaccination regimen , 2. Very® SARS-CoV-2-TrimericS IgG chemiluminescent immunoassay, Diasorin S.p.A., Saluggia, Italy; cut-off value for seroconversion: ≥33.8 BAU/mL). After double mRNA vaccination the SC rate was 48%. Following heterologous triple vaccination an additional 54% of the initial non-responders achieved SC. Altogether, 97 out of 122 KTR (80%) achieved SC after either double mRNA vaccination or the heterologous triple vaccination. Forty-eight of the 142 KTR showed high-level SC after double mRNA vaccination. Twenty patients developed low antibody concentrations (arbitrary threshold <350 BAU/mL). After a third heterologous dose all these 20 patients significantly boosted their humoral response (1391.9 (SD 687.2) vs. 144.8 (SD 94.6) BAU/mL, p < 0.001). Non-responders after heterologous triple vaccination were significantly older , were more often treated with prednisolone or belatacept  and had a shorter median transplantation vintage . They showed a trend of lower mean eGFR  and being treated more often with mycophenolic acid . Higher mycophenolic acid doses did not correlate with inferior antibody response (p = 0.299). As a limitation, our study lacks cellular immune response and neutralizing antibody data. But anti-spike IgG antibodies are highly correlated with neutralizing antibodies, and a level >264 BAU/mL  has been found to be associated with 80% vaccine efficacy against primary symptomatic Covid-19, although limited to the B.1.177 and B.1.1.7 SARS-CoV-2 variant (vs. 4.6 years) and extended interval between second and third dose (109 vs. 80 days) in our cohort compared to the study by Reindl-Schwaighofer et al.  after double mRNA and triple heterologous vaccination . Patient