Bictegravir/emtricitabine/tenofovir alafenamide as first-line treatment in naïve HIV patients in a rapid-initiation model of care: BIC-NOW clinical trial

OBJECTIVE

Multiple strategies have been utilised to reduce the incidence of HIV, including PrEP and rapid antiretroviral therapy initiation. The study objectives were to evaluate the efficacy, safety, satisfaction, treatment adherence, and system retention obtained with rapid initiation of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in naïve patients.

METHODS

This phase IV, multicenter, open-label, single-arm, 48-week clinical trial enrolled patients between January 2020 and June 2022. Adherence to treatment was evaluated with the SMAQ questionnaire and patient satisfaction with the EQ-5D.

RESULTS

Two hundred eight participants were enrolled with mean age of 35.6 years; 87.6% were males; mean CD4 count was 393.5 cells/uL (<200 cells/uL in 22.1%); viral load log was 5.6 (VL>100 000 cop/mL in 43.3%); 22.6% had AIDS, and 4.3% were coinfected with HBV. BIC/FTC/TAF was initiated on the day of their first visit to the HIV specialist in 98.6% of participants, and 9.6% were lost to follow-up. The efficacy at week 48 was 84.1 % by intention-to- treat (ITT), 94.6% by modified ITT, and 98.3% by per protocol analysis. The regimen was discontinued in two subjects (0.9%) during week 1 for grade 3 adverse events. Treatment adherence (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95%; P = 0.49]) and patient satisfaction (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95 P = 0.49]) rates were very high over the 48- week study period.

CONCLUSIONS

BIC/FTC/TAF is an appropriate option for rapid ART initiation in naïve HIV patients, offering high efficacy, safety, durability, treatment adherence, retention in the healthcare system, and patient satisfaction. Number Clinical Trial registration: NCT06177574.

DOLAMA 200: Effectiveness and Safety of a Dual Therapy with Dolutegravir Plus Lamivudine in Treatment-Experienced HIV-1 Infected Real World Participants in Spain

The continuous pharmacological advances in antiretroviral treatment (ART) and the increasing understanding of HIV drug resistance has led to a change in the paradigm of ART optimization in the setting of the viral suppression of treatment-experienced patients with the emerging evidence of the effectiveness and safety of dual therapies. The aim of this study is to determine the antiviral efficacy and safety of switching to Dolutegravir + Lamivudine in people living with HIV, and to analyze the rate of patients with virologic failure (VF). A total of 200 patients were included with a median age of 51 years, 189 cells/µL of nadir CD4+, 13 years on ART and four previous ART regimens. Among the 168 patients who completed a follow-up at 48 weeks, a total of five VFs occurred, resulting in a 2.98% (5/168) VF rate. The results of the intention-to-treat analysis were a VF rate of 2.54% (5/197), and the rate of patients/year with viral suppression was 98.3% (298/303) in the observed data analysis. We observed a significant improvement in mean CD4 lymphocytes, the CD4/CD8 ratio and lipid profiles. The optimization of ART to DTG plus 3TC is a cost-effective switch option for treatment-experienced HIV patients, and also improves their lipid profiles.

Effect of Monotherapy with Darunavir/Ritonavir on Viral Load in Seminal Fluid, and Quality Parameters of Semen in HIV-1-Positive Patients

Patients with human immunodeficiency virus type 1 (HIV-1) who receive antiretroviral therapy (ART) often achieve increased survival and improved quality of life. In this respect, monotherapy with darunavir/ritonavir (mDRV/r) can be a useful treatment strategy. This prospective study analyses the effect of mDRV/r on sperm quality and viral load in a group of 28 patients who had previously been given conventional ART and who had recorded a viral load <20 copies/mL for at least six months. These patients were given mDRV/r at a dose of 800/100 mg for 48 weeks. At baseline (V0), CD4, CD8, FSH, LH and testosterone levels were measured, together with HIV-1 viral load in plasma and semen. In addition, seminal fluid quality was studied before mDRV/r treatment was prescribed. At week 48 (V1), HIV-1 viral load in plasma and semen and the quality of the seminal fluid were again measured. The results obtained indicate that at V0, 10% of the patients with ART had a positive viral load in seminal fluid (>20 copies/ml), and that at V1, after mDRV/r treatment, this figure had fallen to 3%. The quality of seminal fluid was close to normal in 57% of patients at V0 and in 62% at V1. We conclude that, similar to ART, mDRV/r maintains HIV-1 viral load in most patients, and that there is no worsening in seminal fluid quality.

Template to improve glycemic control without reducing adiposity or dietary fat

Drugs that improve chronic hyperglycemia independently of insulin signaling or reduction of adiposity or dietary fat intake may be highly desirable. Ad36, a human adenovirus, promotes glucose uptake in vitro independently of adiposity or proximal insulin signaling. We tested the ability of Ad36 to improve glycemic control in vivo and determined if the natural Ad36 infection in humans is associated with better glycemic control. C57BL/6J mice fed a chow diet or made diabetic with a high-fat (HF) diet were mock infected or infected with Ad36 or adenovirus Ad2 as a control for infection. Postinfection (pi), systemic glycemic control, hepatic lipid content, and cell signaling in tissues pertinent to glucose metabolism were determined. Next, sera of 1,507 adults and children were screened for Ad36 antibodies as an indicator of past natural infection. In chow-fed mice, Ad36 significantly improved glycemic control for 12 wk pi. In HF-fed mice, Ad36 improved glycemic control and hepatic steatosis up to 20 wk pi. In adipose tissue (AT), skeletal muscle (SM), and liver, Ad36 upregulated distal insulin signaling without recruiting the proximal insulin signaling. Cell signaling suggested that Ad36 increases AT and SM glucose uptake and reduces hepatic glucose release. In humans, Ad36 infection predicted better glycemic control and lower hepatic lipid content independently of age, sex, or adiposity. We conclude that Ad36 offers a novel tool to understand the pathways to improve hyperglycemia and hepatic steatosis independently of proximal insulin signaling, and despite a HF diet. This metabolic engineering by Ad36 appears relevant to humans for developing more practical and effective antidiabetic approaches.

MAGUKs, scaffolding proteins at cell junctions, are substrates of different proteases during apoptosis

A major feature of apoptotic cell death is gross structural changes, one of which is the loss of cell–cell contacts. The caspases, executioners of apoptosis, were shown to cleave several proteins involved in the formation of cell junctions. The membrane-associated guanylate kinases (MAGUKs), which are typically associated with cell junctions, have a major role in the organization of protein–protein complexes at plasma membranes and are therefore potentially important caspase targets during apoptosis. We report here that MAGUKs are cleaved and/or degraded by executioner caspases, granzyme B and several cysteine cathepsins in vitro. When apoptosis was induced by UV-irradiation and staurosporine in different epithelial cell lines, caspases were found to efficiently cleave MAGUKs in these cell models, as the cleavages could be prevented by a pan-caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp(OMe)fluoromethylketone. Using a selective lysosomal disrupting agent -leucyl--leucine methyl ester, which induces apoptosis through the lysosomal pathway, it was further shown that MAGUKs are also cleaved by the cathepsins in HaCaT and CaCo-2 cells. Immunohistological data showed rapid loss of MAGUKs at the sites of cell–cell contacts, preceding actual cell detachment, suggesting that cleavage of MAGUKs is an important step in fast and efficient cell detachment.

HPV E6 and MAGUK protein interactions: determination of the molecular basis for specific protein recognition and degradation

It has recently been shown that the high-risk human papillomavirus (HPV) E6 proteins can target the PDZ-domain containing proteins, Dlg, MUPP-1, MAGI-1 and hScrib for proteasome-mediated degradation. However, the E6 proteins from HPV-16 and HPV-18 (the two most common high-risk virus types) differ in their ability to target these proteins in a manner that correlates with their malignant potential. To investigate the underlying mechanisms for this, we have mutated HPV-16 and HPV-18 E6s to give each protein the other's PDZ-binding motif. Analysis of these mutants shows that the greater ability of HPV-18 E6 to bind to these proteins and to target them for degradation is indeed due to a single amino acid difference. Using a number of assays, we show that the E6 proteins interact specifically with only one of the five PDZ domains of MAGI-1, and this is the first interaction described for this particular PDZ domain. We also show that the guanylate kinase homology domain and the regions of MAGI-1 downstream of amino acid 733 are not required for the degradation of MAGI-1. Finally, in a series of comparative analyses, we show that the degradation of MAGI-1 occurs through a different mechanism from that used by the E6 protein to induce the degradation of Dlg and p53.

Several E4 region functions influence mammary tumorigenesis by human adenovirus type 9

Among oncogenic adenoviruses, human adenovirus type 9 (Ad9) is unique in eliciting exclusively estrogen-dependent mammary tumors in rats and in not requiring viral E1 region transforming genes for tumorigenicity. Instead, studies with hybrid viruses generated between Ad9 and the closely related nontumorigenic virus Ad26 have roughly localized an Ad9 oncogenic determinant(s) to a segment of the viral E4 region containing open reading frame 1 (E4-ORF1), E4-ORF2, and part of E4-ORF3. Although subsequent findings have shown that E4-ORF1 codes for an oncoprotein essential for tumorigenesis by Ad9, it is not known whether other E4 region functions may similarly play a role in this process. We report here that new results with Ad9/Ad26 hybrid viruses demonstrated that the minimal essential Ad9 E4-region DNA sequences include portions of both E4-ORF1 and E4-ORF2. Investigations with Ad9 mutant viruses additionally showed that the E4-ORF1 protein and certain E4-ORF2 DNA sequences are necessary for Ad9-induced tumorigenesis, whereas the E4-ORF2 and E4-ORF3 proteins are not. In fact, the E4-ORF3 protein was found to antagonize this process. Also pertinent was that certain crucial nucleotide differences between Ad9 and Ad26 within E4-ORF1 and E4-ORF2 were found to be silent with respect to the amino acid sequences of the corresponding proteins. Furthermore, supporting a prominent role for the E4-ORF1 oncoprotein in Ad9-induced tumorigenesis, an E1 region-deficient Ad5 vector that expresses the Ad9 but not the Ad26 E4-ORF1 protein was tumorigenic in rats and, like Ad9, promoted solely mammary tumors. These findings argue that the E4-ORF1 oncoprotein is the major oncogenic determinant of Ad9 and that an undefined regulatory element(s) within the E4 region represents a previously unidentified second function likewise necessary for tumorigenesis by this virus.

Interactions of the PDZ-protein MAGI-1 with adenovirus E4-ORF1 and high-risk papillomavirus E6 oncoproteins

The oncoproteins of small DNA tumor viruses promote tumorigenesis by complexing with cellular factors intimately involved in the control of cell proliferation. The major oncogenic determinants for human adenovirus type 9 (Ad9) and high-risk human papillomaviruses (HPV) are the E4-ORF1 and E6 proteins, respectively. These seemingly unrelated viral oncoproteins are similar in that their transforming activities in cells depend, in part, on a carboxyl-terminal PDZ domain-binding motif which mediates interactions with the cellular PDZ-protein DLG. Here we demonstrated that both Ad9 E4-ORF1 and high-risk HPV E6 proteins also bind to the DLG-related PDZ-protein MAGI-1. These interactions resulted in MAGI-1 being aberrantly sequestered in the cytoplasm by the Ad9 E4-ORF1 protein or being targeted for degradation by high-risk HPV E6 proteins. Transformation-defective mutant viral proteins, however, were deficient for these activities. Our findings indicate that MAGI-1 is a member of a select group of cellular PDZ proteins targeted by both adenovirus E4-ORF1 and high-risk HPV E6 proteins and, in addition, suggest that the tumorigenic potentials of these viral oncoproteins depend, in part, on an ability to inhibit the function of MAGI-1 in cells.

HPV E6 targeted degradation of the discs large protein: evidence for the involvement of a novel ubiquitin ligase

The Discs Large (DLG) tumour suppressor protein is targeted for ubiquitin mediated degradation by the high risk human papillomavirus (HPV) E6 proteins. In this study we have used a mutational analysis of E6 in order to investigate the mechanism by which this occurs. We first show that the differences in the affinities of HPV-16 and of HPV-18 E6 proteins for binding DLG is reflected in their respective abilities to target DLG for degradation. A mutational analysis of HPV-18 E6 has enabled us to define regions within the carboxy terminal half of the protein which are essential for the ability of E6 to direct the degradation of DLG. Mutants within the amino terminal portion of E6 which have lost the ability to bind the E6-AP ubiquitin ligase, as measured by their ability to degrade p53, nonetheless retain the ability to degrade DLG. Significant levels of DLG degradation are also obtained using wheat germ extracts which lack E6-AP. Finally, we show that the transfer of the DLG binding domain onto the low risk HPV-6 E6 confers DLG binding activity to that protein and, most significantly, allows HPV-6 E6 to target DLG for degradation. These results indicate that E6 mediated degradation of DLG does not involve the E6-AP ubiquitin ligase and, in addition, shows that the high and low risk HPV E6 proteins most likely share a common cellular intermediary in the ubiquitin pathway.

Oncogenic human papillomavirus E6 proteins target the discs large tumour suppressor for proteasome-mediated degradation

Previous studies have shown that the oncogenic HPV E6 proteins form a complex with the human homologue of the Drosophila tumour suppressor protein, discs large (Dlg). This is mediated by the carboxy terminus of the E6 proteins and involves recognition of at least one PDZ domain of Dlg. This region of E6 is not conserved amongst E6 proteins from the low risk papillomavirus types and, hence, binding of HPV E6 proteins to Dlg correlates with the oncogenic potential of these viruses. We have performed studies to investigate the consequences of the interaction between E6 and Dlg. Mutational analysis of both the HPV18 E6 and Dlg proteins has further defined the regions of E6 and Dlg necessary for complex formation. Strikingly, co-expression of wild type HPV18 E6 with Dlg in vitro or in vivo results in a dramatic decrease in the amount of Dlg protein, whereas mutants of E6 which fail to complex with Dlg have minimal effect on Dlg protein levels. The oncogenic HPV16 E6 also decreased the Dlg levels, but this was not observed with the low risk HPV11 E6 protein. Moreover, a region within the first 544 amino acids of Dlg containing the three PDZ domains confers susceptibility to E6 mediated degradation. Finally, treatment of cells with a proteasome inhibitor overrides the capacity of E6 to degrade Dlg. These results demonstrate that Dlg is targeted by high risk HPV E6 proteins for proteasome mediated degradation.

Mammary tumors induced by human adenovirus type 9: a role for the viral early region 4 gene

Human adenovirus type 9 (Ad9) elicits exclusively estrogen-dependent mammary tumors when injected into female rats. Three different histological types of mammary tumor (benign fibroadenomas, phyllodes tumors, and malignant solid sarcomas) have been described in Ad9-infected animals, with benign fibroadenomas being seen most frequently. Interestingly, in contrast to other adenoviruses, in which oncogenic viral functions are entirely encoded within the E1 region, Ad9 requires an E4 region transforming protein (ORF1) for its unique mammary oncogenicity. Studies of Ad9-induced rat mammary tumors may lead to a detailed molecular understanding for the development of fibroadenoma, a common human breast tumor.

Requirement for the adenovirus type 9 E4 region in production of mammary tumors

Oncogenic viruses demonstrating a strict tropism for the mammary gland provide special opportunities to study the susceptibility of this tissue to neoplasia. In rats, human adenovirus type 9 (Ad9) elicits mammary fibroadenomas that are similar to common breast tumors in women, as well as phyllodes-like tumors and mammary sarcomas. By constructing recombinant adenoviruses between Ad9 and Ad26 (a related nontumorigenic virus), it was shown that the Ad9 E4 region was absolutely required to produce these mammary tumors. This indicates that an adenovirus gene located outside the classic transforming region (E1) can significantly influence the in vivo oncogenicity of an adenovirus. Consistent with a direct role in mammary gland oncogenesis, the Ad9 E4 region also exhibited transforming properties in vitro. Therefore, the Ad9 E4 region is a viral oncogene specifically involved in mammary gland tumorigenesis.

Human adenovirus type 9-induced rat mammary tumors

Following subcutaneous inoculation of newborn Wistar-Furth rats with human adenovirus type 9 (Ad9), 16 of 16 female and 0 of 11 male rats developed mammary tumors. Tumor-positive animals usually developed tumors in multiple glands. Histopathological analyses indicated that three general categories of tumor could be identified. Mammary fibroadenomas were the most common tumor type encountered, but phyllodeslike tumors and solid sarcomas were also frequently found. In situ hybridization and immunohistochemical techniques established that benign fibroadenomas were derived from mammary fibroblasts (collagen type I- and vimentin-positive cells) and that malignant tumors were derived from myoepithelial cells (collagen type IV-, vimentin-, and muscle-specific actin-positive cells). The fact that mammary tumors were limited to female rats suggested that female hormones are essential for tumor growth and development. In this regard, ovariectomy of Ad9-infected female rats prevented tumor development, while subsequent diethylstilbestrol (DES) treatment elicited tumor formation. In addition, Ad9-infected and castrated male rats which received DES also developed mammary tumors. Established male mammary tumors regressed when DES treatment was stopped and reappeared after DES treatment was resumed. Together, these results indicate that estrogen is required for both initiation and maintenance of Ad9-induced mammary tumors. Southern blot analysis of high-molecular-weight tumor DNA showed that mammary tumor cells contained single or multiple integrated copies of the entire Ad9 genome. RNase protection experiments established that estrogen receptor as well as Ad9 E1a and E4 mRNAs were expressed in mammary tumors, but Ad9 E3 and, surprisingly, E1b mRNAs were not expressed at detectable levels.

Renal scleroderma: comparison of different modalities of treatment

A patient with scleroderma and severe renal failure was initially treated with hemodialysis and minoxidil (Loniten) without any improvement in her skin involvement. At a later date bilateral nephrectomy and a successful cadaveric renal transplant were performed. Her cutaneous manifestations have improved remarkably during the four years since transplantation. Because these patients do not tolerate hemodialysis very well, renal transplantation appears to be the most effective form of treatment, with the possible added benefit of cutaneous improvement.

Thromboembolism associated with pigtail catheters

Three incidents of asymptomatic arterial thromboembolism associated with polyurethane pigtail catheters occurred during 1,417 cases of left ventricular angiocardiography. No similar incident occurred with polyethylene pigtail or (dacron) Eppendorf and Gensini (style) catheters. In vitro comparison of hydraulic characteristics of polyurethane (Cordis) and polyethylene (Cook) pigtail catheters showed higher flow-pressure transmission through the tip of the Cordis polyurethane catheter favoring dislodgment of any existing clot. The problem of thrombogencity of polyethylene compared with polyurethane remains unsettled. Our experience with polyurethane pigtail catheters has resulted in limitation of their use in our laboratory.

Paroxysmal atrial tachycardia with exit block

A case of atrial tachycardia with A-V block is reported with a basic cycle length of 0.40 sec corresponding to an atrial rate of 150/min. Pauses of various length in atrial activity [see figure in the PDF file] were observed, and each was a multiple of 0.20 sec. These were attributed to the effect of an exit block. It was postulated that the actual atrial rate was 300/min, that is, double the manifest rate. In fact, doubling of the manifest atrial rate was temporarily produced by vagus stimulation and was observed also in spontaneous attacks which mimicked closely atrial flutter. These observations underline the difficulty of separating paroxysmal atrial tachycardia and flutter.