OBJECTIVE:To evaluate the antiviral activity, safety, pharmacokinetics, and pharmacokinetics/pharmacodynamics of short-term monotherapy with tenofovir alafenamide (TAF), a next-generation tenofovir ...(TFV) prodrug.
DESIGN:A phase 1b, randomized, partially blinded, active- and placebo-controlled, dose-ranging study.
METHODS:Treatment-naive and experienced HIV-1–positive adults currently off antiretroviral therapy were randomized to receive 8, 25, or 40 mg TAF, 300 mg tenofovir disoproxil fumarate (TDF), or placebo, each once daily for 10 days.
RESULTS:Thirty-eight subjects were enrolled. Baseline characteristics were similar across dose groups. Significant reductions in plasma HIV-1 RNA from baseline to day 11 were observed for all TAF dose groups compared with placebo (P < 0.01), with a median decrease of 1.08–1.73 log10 copies per milliliter, including a dose–response relationship for viral load decrease up to 25 mg. At steady state, 8, 25, and 40 mg TAF yielded mean TFV plasma exposures area under the plasma concentration–time curve (AUCtau) of 97%, 86%, and 79% lower, respectively, as compared with the TFV exposures observed with 300 mg TDF. For 25 and 40 mg TAF, the mean intracellular peripheral blood mononuclear cell tenofovir diphosphate AUCtau was ∼7-fold and ∼25-fold higher, relative to 300 mg TDF.
CONCLUSIONS:Compared with 300 mg TDF, TAF demonstrated more potent antiviral activity, higher peripheral blood mononuclear cell intracellular tenofovir diphosphate levels, and lower plasma TFV exposures, at approximately 1/10th of the dose. This may translate into greater antiviral efficacy, a higher barrier to resistance, and an improved safety profile relative to TDF, supporting further investigation of TAF dosed once daily in HIV-infected patients.
Antiretroviral medications can be taken by HIV-negative persons to prevent HIV infection, also known as pre-exposure prophylaxis (PrEP). PrEP was first shown to be effective during the iPrEX study. ...We conducted a survey involving HIV healthcare providers to document their attitudes and prescribing practices about PrEP in response to this study. An online survey was completed by 189 members and credentialees of the American Academy of HIV Medicine between April 2011 and September 2011. Ninety percent of respondents were familiar with the results of the iPrEx study, and most (78%) were familiar with CDC's interim guidance regarding the use of PrEP in MSM. Only 19% of respondents had prescribed PrEP. The majority of PrEP prescribers were compliant with CDC interim guidance; however, only 61% screened for hepatitis B. Of PrEP prescribers, 78% prescribed to MSM, 31% to MSW, and 28% to WSM. Greatest concerns about prescribing PrEP included development of antiretroviral resistance (32%), potential increase in high-risk behavior, (22%) and poor medication adherence (21%). Fifty-eight percent stated that HIV serodiscordance within a relationship most influenced their decision to prescribe PrEP to the HIV-seronegative partner. This study demonstrates that, despite awareness of the efficacy of PrEP, its use is limited. Survey participants used PrEP most commonly in MSM; however, a significant percentage also prescribed PrEP to women. The best candidate for PrEP is felt to be individuals in an HIV-serodiscordant relationship. Limitations to our study included a low response rate, changes in the evidence base, and the novelty of PrEP.
Two-drug regimens (2DR) to treat HIV infection have the potential to reduce long-term toxicity and increase therapeutic options for people living with HIV (PLHIV). Prior phase III trials, SWORD-1 and ...SWORD-2, as well as GEMINI-1 and GEMINI-2, have demonstrated that a dolutegravir-based 2DR is as effective as three- or four-drug regimens among virologically suppressed patients. Limited information exists, however, on patient and provider experiences with 2DR to inform roll-out and integration into routine clinical care.
We conducted 39 in-depth interviews with PLHIV currently on 2DR in the context of routine care and 8 of their clinical care providers in the United States (U.S.) and Spain. Participants included 33 male and 6 female PLHIV and 8 providers. Interview topics explored perceptions of and experiences with 2DR compared to prior anti-retroviral regimens (ARVs), side effects, patient satisfaction, and clinical performance. Interviews were audio-recorded, transcribed and analyzed using thematic content analysis.
Participants viewed 2DR as a significant and positive advance, in terms of its ability to effectively treat HIV with reduced toxicity and essentially no reported side effects. Patients noted the central role providers played in the decision to switch to a 2DR regimen and, among U.S. participants, the importance of insurance coverage making this preferred option feasible. Patients and providers agreed that a 2DR regimen would be appropriate for any PLHIV regardless of whether they were treatment naïve or had significant experience with ARVs.
Participants' experiences with a 2DR regimen were positive with no participants, reporting side effects and all reporting continued viral suppression. Providers valued the reduced toxicity offered by 2DR and served as the primary gateway to a transition to 2DR for patients in both settings. This study provides a foundation for further research on the transition to 2DR regimens in other populations and contexts including low- and middle-income settings.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Long-acting injectable antiretroviral therapy (LA ART) may be an alternative for people living with HIV (PLHIV) with adherence challenges or who prefer not to take pills. Using in-depth interviews, ...this study sought to understand the experiences of PLHIV (n = 53) participating in Phase 3 LA ART trials in the United States and Spain. The most salient consideration when contemplating LA ART was its clinical efficacy; many participants reported wanting to ensure that it worked as well as daily oral ART, including with less frequent dosing (every 8 versus 4 weeks). While injection side effects were often reported, most participants felt that regimen benefits outweighed such drawbacks. Participants described the main benefit of LA ART as the “freedom” it afforded both logistically and psychosocially, including through reduced HIV stigma. Findings highlight the importance of patient-provider communication related to weighing potential benefits and side effects and the continued need to address HIV stigma.
Long-acting injectable antiretroviral therapy (LA ART) has been shown to be non-inferior to daily oral ART, with high patient satisfaction and preference to oral standard of care in research to date, ...and has recently been approved for use in the United States and Europe. This study examined the perspectives of health care providers participating in LA ART clinical trials on potential barriers and solutions to LA ART roll-out into real world settings.
This analysis draws on two data sources: (1) open-ended questions embedded in a structured online survey of 329 health care providers participating in the ATLAS-2 M trial across 13 countries; and (2) in-depth interviews with 14 providers participating in FLAIR/ ATLAS/ATLAS-2 M trials in the United States and Spain. Both assessments explored provider views and clinic dynamics related to the introduction of LA ART and were analyzed using thematic content analysis. The Consolidated Framework for Implementation Research (CFIR) was drawn on as the conceptual framework underpinning development of a model depicting study findings.
Barriers and proposed solutions to LA ART implementation were identified at the individual, clinic and health system levels. Provider perceptions of patient level barriers included challenges with adhering to frequent injection appointments and injection tolerability. Proposed solutions included patient education, having designated staff for clinic visit retention, and clinic flexibility with appointment scheduling. The main provider concern was identifying appropriate candidates for LA ART; proposed solutions focused on patient provider communication and decision making. Clinic level barriers included the need for additional skilled individuals to administer injections, shifts in workflow as demand increases and the logistics of cold-chain storage. Proposed solutions included staff hiring and training, strategic planning around workflow and logistics, and the possibility of offering injections in other settings, including the home. Health system level barriers included cost and approvals from national regulatory bodies. Potential solutions included governments subsidizing treatment, ensuring cost is competitive with oral ART, and offering co-pay assistance.
Results suggest the importance of multi-level support systems to optimize patient-provider communication and treatment decision-making; clinic staffing, workflow, logistics protocols and infrastructure; and cost-related factors within a given health system.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
INTRODUCTION:Direct comparison of the efficacy and safety of different agents is needed to guide selection of optimal treatment regimens for therapy-naive HIV-1-infected patients.
METHODS:Gemini was ...a 48-week, multicenter, open-label, noninferiority trial in treatment-naive HIV-1-infected adults randomized to either saquinavir/ritonavir (SQV/r) 1000 mg/100 mg twice a day or lopinavir/ritonavir (LPV/r) 400 mg/100 mg twice a day, each with emtricitabine/tenofovir 200 mg/300 mg every day.
RESULTS:A similar proportion of participants in the SQV/r (n = 167) and LPV/r (n = 170) arms had HIV-1 RNA levels <50 copies per milliliter at week 4864.7% vs 63.5% and estimated difference in proportion for noninferiority1.14%, 96% confidence interval−9.6 to11.9 (P < 0.012), confirming that SQV/r was noninferior to LPV/r treatment. There were no significant differences in week 48 CD4 counts between arms. The rate and severity of adverse events were similar in both groups. There were no significant differences in the median change from baseline between arms in plasma lipids except for triglyceride levels, which were significantly higher in the LPV/r at week 48.
CONCLUSIONS:In treatment-naive, HIV-1-infected patients, SQV/r treatment was noninferior in virologic suppression at 48 weeks to LPV/r treatment and offered a better triglyceride profile.
Long-acting injectable antiretroviral therapy has been shown to be non-inferior to daily oral antiretroviral therapy in clinical trials and may soon become part of clinical care. While most trial ...participants to date have been men, approximately one quarter of ongoing Phase 3 trial participants are women offering an important opportunity to understand how long-acting antiretroviral therapy is perceived and experienced by women. We conducted in-depth interviews with 80 people living with HIV participating in Phase 2 and 3 clinical trials of long-acting antiretroviral therapy in the USA and Spain. Fifteen percent (12/80) of trial participants interviewed were women. Interviews were audio-recorded, transcribed and coded using content analysis, focused on gender-specific themes. Women shared many of the positive perceptions expressed by men but also had unique perspectives, including finding that long-acting antiretroviral therapy addressed the challenge of remembering pills amidst busy day-to-day realities including multiple roles and responsibilities, is less time consuming and creates less stress compared to oral antiretroviral therapy, and is emotionally freeing and empowering. The gendered nature of women's lives shaped why and how they were satisfied with long-acting antiretroviral therapy. Findings can inform interventions and support systems to facilitate uptake of and adherence to long-acting antiretroviral therapy in women.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Vaccination with inactivated (killed) whole-virus particles has been used to prevent a wide range of viral diseases. However, for an HIV vaccine this approach has been largely negated due to inherent ...safety concerns, despite the ability of killed whole-virus vaccines to generate a strong, predominantly antibody-mediated immune response in vivo. HIV-1 Clade B NL4-3 was genetically modified by deleting the nef and vpu genes and substituting the coding sequence for the Env signal peptide with that of honeybee melittin signal peptide to produce a less virulent and more replication efficient virus. This genetically modified virus (gmHIV-1
) was inactivated and formulated as a killed whole-HIV vaccine, and then used for a Phase I human clinical trial (Trial Registration: Clinical Trials NCT01546818). The gmHIV-1
was propagated in the A3.01 human T cell line followed by virus purification and inactivation with aldrithiol-2 and γ-irradiation. Thirty-three HIV-1 positive volunteers receiving cART were recruited for this observer-blinded, placebo-controlled Phase I human clinical trial to assess the safety and immunogenicity.
Genetically modified and killed whole-HIV-1 vaccine, SAV001, was well tolerated with no serious adverse events. HIV-1
-specific PCR showed neither evidence of vaccine virus replication in the vaccine virus-infected human T lymphocytes in vitro nor in the participating volunteers receiving SAV001 vaccine. Furthermore, SAV001 with adjuvant significantly increased the pre-existing antibody response to HIV-1 proteins. Antibodies in the plasma of vaccinees were also found to recognize HIV-1 envelope protein on the surface of infected cells as well as showing an enhancement of broadly neutralizing antibodies inhibiting tier I and II of HIV-1 B, D, and A subtypes.
The killed whole-HIV vaccine, SAV001, is safe and triggers anti-HIV immune responses. It remains to be determined through an appropriate trial whether this immune response prevents HIV infection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A new class of antiretroviral drugs is now available to the HIV provider: The CCR5 Antagonists belong to a group of entry inhibitors with a novel mechanism of action. While these antagonists do not ...directly interfere with any of the steps of HIV replication, they block the CCR5 receptor, one of the co-receptors HIV uses to enter its target cell. Thus CCR5 antagonists are able to prevent infection of the cell and represent a new and unique mechanism for the treatment of HIV. There is great interest in utilizing this new drug class in early treatment of HIV to prevent infection of large cell pools; CCR5 antagonists even may be useful tools in the various settings of exposure prophylaxis. Maraviroc is now approved in both the European Union and the United States for the treatment of HIV infection. This is the first medication belonging to the new class of CCR5 antagonists, and the first approval of an orally available drug in a new class since 1996. Aplaviroc, maraviroc, and vicriviroc are small molecule inhibitors of CCR5 that block HIV-1 infection in vitro and reduce plasma HIV-1 RNA in HIV infected subjects by approximately 1.5 log10 copies/mL over 10-14 days when given as single agents. Very limited data is available on the use of CCR5 antagonists in treatment naive patients due to early termination of many trials because of inferior performance or toxicity and at the time of this writing in August 2007 there is only one ongoing non-inferiority trial in the naive patient population. The 48 week interim results of this trial using twice daily maraviroc were reported at the International AIDS Society meeting in July 2007. Maraviroc compared to efavirenz was non-inferior in regards to percentage of subjects reaching viral loads below 400 copies/mL, but not so for the analysis of subjects reaching viral loads below 50 copies/mL. On the other hand maraviroc had a superior side-effect profile, fewer adverse events and a greater increase of CD4 cell count than efavirenz. These data will revitalize the interest in CCR5 antagonists as a treatment option for the treatment-naive patients. In order to be used as first line drugs, CCR5 antagonists face a number of challenges: They will have to be proven to be as potent, durable, safe, and convenient as current available options. Important questions unique to this new class will have to be answered: What are the mechanisms and risks of tropism change? What is the role and needed frequency of tropism testing, and what efficacy is seen in patients with dual-tropic/mixed infection in the long term? Clearly until we have answers to these questions CCR5 antagonists should be reserved for the treatment-experienced patient population with limited treatment options.
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