New clinical trial designs for HIV vaccine evaluation

The initial interplay between HIV and mucosal innate immunity

Human Immunodeficiency Virus (HIV) is still one of the major global health issues, and despite significant efforts that have been put into studying the pathogenesis of HIV infection, several aspects need to be clarified, including how innate immunity acts in different anatomical compartments. Given the nature of HIV as a sexually transmitted disease, one of the aspects that demands particular attention is the mucosal innate immune response. Given this scenario, we focused our attention on the interplay between HIV and mucosal innate response: the different mucosae act as a physical barrier, whose integrity can be compromised by the infection, and the virus-cell interaction induces the innate immune response. In addition, we explored the role of the mucosal microbiota in facilitating or preventing HIV infection and highlighted how its changes could influence the development of several opportunistic infections. Although recent progress, a proper characterization of mucosal innate immune response and microbiota is still missing, and further studies are needed to understand how they can be helpful for the formulation of an effective vaccine.

Approaches to enabling rapid evaluation of innovations in health and social care: a scoping review of evidence from high-income countries

OBJECTIVE

The COVID-19 pandemic increased the demand for rapid evaluation of innovation in health and social care. Assessment of rapid methodologies is lacking although challenges in ensuring rigour and effective use of resources are known. We mapped reports of rapid evaluations of health and social care innovations, categorised different approaches to rapid evaluation, explored comparative benefits of rapid evaluation, and identified knowledge gaps.

DESIGN

Scoping review.

DATA SOURCES

MEDLINE, EMBASE and Health Management Information Consortium (HMIC) databases were searched through 13 September 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included publications reporting primary research or methods for rapid evaluation of interventions or services in health and social care in high-income countries.

DATA EXTRACTION AND SYNTHESIS

Two reviewers developed and piloted a data extraction form. One reviewer extracted data, a second reviewer checked 10% of the studies; disagreements and uncertainty were resolved through consensus. We used narrative synthesis to map different approaches to conducting rapid evaluation.

RESULTS

We identified 16 759 records and included 162 which met inclusion criteria.We identified four main approaches for rapid evaluation: (1) Using methodology designed specifically for rapid evaluation; (2) Increasing rapidity by doing less or using less time-intensive methodology; (3) Using alternative technologies and/or data to increase speed of existing evaluation method; (4) Adapting part of non-rapid evaluation.The COVID-19 pandemic resulted in an increase in publications and some limited changes in identified methods. We found little research comparing rapid and non-rapid evaluation.

CONCLUSIONS

We found a lack of clarity about what 'rapid evaluation' means but identified some useful preliminary categories. There is a need for clarity and consistency about what constitutes rapid evaluation; consistent terminology in reporting evaluations as rapid; development of specific methodologies for making evaluation more rapid; and assessment of advantages and disadvantages of rapid methodology in terms of rigour, cost and impact.

Multi-arm, multi-stage randomised controlled trials for evaluating therapeutic HIV cure interventions

The evaluation of immune-based approaches to achieve an antiretroviral therapy free remission of HIV infection requires proven efficacy through antiretroviral therapy interruption placebo-controlled trials. This approach is not without risk to participants and innovative trial designs need to be developed that minimise the number of participants treated with placebo and ineffective candidates. Multi-arm, multi-stage (MAMS) trial designs can be used in this context to accelerate the development of an immune-based therapeutic agent for HIV cure. Issues related to implementing a MAMS design within the planned EHVA T01 trial are considered here. EHVA T01 is a multicentre, MAMS, double-blind, phase 1 and 2 trial that aims to evaluate the effect of immune interventions on viral control in HIV-1 infected participants following analytic treatment interruption. The application of a MAMS design increases the likelihood that the EHVA T01 trial will identify a successful treatment and minimises the number of participants undergoing analytical treatment interruptions who have been treated with futile agents. The use of a MAMS design is a promising strategy to evaluate complex immune-based approaches aimed at curing HIV-infection, particularly relevant to the pipeline with multiple agents requiring examination.

Recent developments in clinical trial designs for HIV vaccine research

HIV vaccine strategies are expected to be a crucial component for controlling the HIV epidemic. Despite the large spectrum of potential candidate vaccines for both prophylactic and therapeutic use, the overall development process of an efficacious HIV vaccine strategy is lengthy. The design of clinical trials and the progression of a candidate strategy through the different clinical development stages remain methodologically challenging, mainly due to the lack of validated correlates of protection. In this review, we describe recent advances in clinical trial designs to increase the efficiency of the clinical development of candidate HIV vaccine strategies. The methodological aspects of the designs for early- (phase I and II) and later -stage (phase IIB and III) development are discussed, taking into account the specificities of both prophylactic and therapeutic HIV vaccine development.

HIV vaccines: a brief overview

The scope of the article is to review the different approaches that have been used for HIV vaccines. The review is based on articles retrieved by PubMed and clinical trials from 1990 up to date. The article discusses virus complexity, protective and non-protective immune responses against the virus, and the most important approaches for HIV vaccine development.