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BACKGROUND: Despite Africa's significant infectious disease burden, it is underrepresented in global vaccine clinical trials. While this trend is slowly reversing, it is important to recognize and mitigate the challenges that arise when conducting vaccine clinical trials in this environment. These challenges stem from a variety of factors peculiar to the population and may negatively impact adverse event collection and reporting if not properly addressed. METHODS: As a team of clinical researchers working within the MRCG (Medical Research Council Unit The Gambia), we have conducted 12 phase 1 to 3 vaccine trials over the past 10 years. In this article, we discuss the challenges we face and the strategies we have developed to improve the collection and reporting of adverse events in low-income settings. OUTCOME: Healthcare-seeking behaviors in the Gambia are influenced by spiritual and cultural beliefs as well as barriers to accessing orthodox healthcare; participants in trials may resort to non-orthodox care, reducing the accuracy of reported adverse events. To address this, trial eligibility criteria prohibit self-treatment and herbal product use during trials. Instead, round-the-clock care is provided to trial participants, facilitating safety follow-up. Constraints in the healthcare system in the Gambia such as limitations in diagnostic tools limit the specificity of diagnosis when reporting adverse events. To overcome these challenges, the Medical Research Council Unit maintains a Clinical Services Department, offering medical care and diagnostic services to study participants. Sociocultural factors, including low literacy rates and social influences, impact adverse event collection. Solicited adverse events are collected during home visits on paper-based or electronic report forms. Community engagement meetings are held before each study starts to inform community stakeholders about the study and answer any questions they may have. These meetings ensure that influential members of the community understand the purpose of the study and the risks and benefits of participating in the trial. This understanding makes them more likely to support participation within their communities. CONCLUSION: Conducting ethical vaccine clinical trials in resource-limited settings requires strategies to accurately collect and report adverse events. Our experiences from the Gambia offer insights into adverse event collection in these settings.

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OBJECTIVES: Valuing and pricing the components of combination therapies can be difficult because of competition law issues, difficulty implementing different prices for the same product in alternative uses, and attributing value to each component of the combination. We propose a value attribution solution that allows all combination components to be priced according to their relative value in the combination. METHODS: We developed a value attribution solution that is universal, symmetrical, and neutral to each combination constituent, regardless of whether it is the backbone or the add-on, and complete, meaning that it will always attribute the full value of the combination between the component parts. Moreover, it can be applied to any number of components in the combination (eg, triplets or quadruplets). We compared this solution with 2 other existing approaches. RESULTS: The results of the proposed value attribution solution sit between those of the 2 other value attribution approaches as it combines elements of each. As the degree of additivity moves further away from one in either direction, then our general approach ratios also move, reflecting the impact of the incremental value. CONCLUSIONS: The proposed value attribution solution for combination therapies differs from 2 existing approaches by being universally applicable and allowing for symmetry when neutral to the constituent components of the combination. To optimally contribute to policy debate and practice, various requirements for its implementation need to be well understood, including how to overcome (1) partial information, (2) whether its assumptions can be relaxed, and (3) implementation issues.

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BACKGROUND: Microneedle patches (MNPs) have been ranked as the highest global priority innovation for overcoming immunisation barriers in low-income and middle-income countries. This trial aimed to provide the first data on the tolerability, safety, and immunogenicity of a measles and rubella vaccine (MRV)-MNP in children. METHODS: This single-centre, phase 1/2, double-blind, double-dummy, randomised, active-controlled, age de-escalation trial was conducted in The Gambia. To be eligible, all participants had to be healthy according to prespecified criteria, aged 18-40 years for the adult cohort, 15-18 months for toddlers, or 9-10 months for infants, and to be available for visits throughout the follow-up period. The three age cohorts were randomly assigned in a 2:1 ratio (adults) or 1:1 ratio (toddlers and infants) to receive either an MRV-MNP (Micron Biomedical, Atlanta, GA, USA) and a placebo (0·9% sodium chloride) subcutaneous injection, or a placebo-MNP and an MRV subcutaneous injection (MRV-SC; Serum Institute of India, Pune, India). Unmasked staff ransomly assigned the participants using an online application, and they prepared visually identical preparations of the MRV-MNP or placebo-MNP and MRV-SC or placebo-SC, but were not involved in collecting endpoint data. Staff administering the study interventions, participants, parents, and study staff assessing trial endpoints were masked to treatment allocation. The safety population consists of all vaccinated participants, and analysis was conducted according to route of MRV administration, irrespective of subsequent protocol deviations. The immunogenicity population consisted of all vaccinated participants who had a baseline and day 42 visit result available, and who had no protocol deviations considered to substantially affect the immunogenicity endpoints. Solicited local and systemic adverse events were collected for 14 days following vaccination. Unsolicited adverse events were collected to day 180. Age de-escalation between cohorts was based on the review of the safety data to day 14 by an independent data monitoring committee. Serum neutralising antibodies to measles and rubella were measured at baseline, day 42, and day 180. Analysis was descriptive and included safety events, seroprotection and seroconversion rates, and geometric mean antibody concentrations. The trial was registered with the Pan African Clinical Trials Registry PACTR202008836432905, and is complete. FINDINGS: Recruitment took place between May 18, 2021, and May 27, 2022. 45 adults, 120 toddlers, and 120 infants were randomly allocated and vaccinated. There were no safety concerns in the first 14 days following vaccination in either adults or toddlers, and age de-escalation proceeded accordingly. In infants, 93% (52/56; 95% CI 83·0-97·2) seroconverted to measles and 100% (58/58; 93·8-100) seroconverted to rubella following MRV-MNP administration, while 90% (52/58; 79·2-95·2) and 100% (59/59; 93·9-100) seroconverted to measles and rubella respectively, following MRV-SC. Induration at the MRV-MNP application site was the most frequent local reaction occurring in 46 (77%) of 60 toddlers and 39 (65%) of 60 infants. Related unsolicited adverse events, most commonly discolouration at the application site, were reported in 35 (58%) of 60 toddlers and 57 (95%) of 60 infants that had received the MRV-MNP. All local reactions were mild. There were no related severe or serious adverse events. INTERPRETATION: The safety and immunogenicity data support the accelerated development of the MRV-MNP. FUNDING: Bill & Melinda Gates Foundation.

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PURPOSE: To evaluate whether the volume of wash out rinse after povidone iodine (PI) application for intravitreal injections (IVI) affects patients' ocular surface irritation. METHODS: This was a prospective, single-masked, randomized-controlled trial consisting of 142 subjects. A total of 51, 45, and 46 patients received 3-mL, 10-mL, and 15-mL of ocular rinse respectively. Reductions in the Ocular Surface Disease Index (OSDI) and the Standardized Patient Evaluation of Eye Dryness II (SPEED II) surveys, conducted before and at 24-72 h post-injection, were analyzed. RESULTS: There was no statistical difference in objective dry eye findings of Schirmer test (p-value = 0.788), tear break-up time (p-value = 0.403), Oxford fluorescein grade (p-value = 0.424) between the study groups prior to injections. Dry eye symptoms as measured by reductions in the OSDI and SPEEDII scores were not different between the study groups (p-value = 0.0690 and 0.6227, respectively). CONCLUSION: There is no difference in patients' ocular surface irritation between 3-mL, 10-mL, and 15-mL post injection rinse. Given the large number of IVIs performed, modification of practice patterns based on these findings could lead to significant reduction in global cost burden for IVIs.

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BACKGROUND: Home delivery and monitoring of antiretroviral therapy (ART) is convenient, overcomes logistical barriers, and could increase individual ART adherence and viral suppression. With client payment and sufficient health benefits, this strategy could be scalable. The aim of the Deliver Health Study was to test the acceptability and efficacy of a user fee for home ART monitoring and delivery. METHODS: We conducted a randomised trial, the Deliver Health Study, of a fee for home delivery of ART compared with free clinic ART delivery in South Africa. People with HIV who were 18 years or older and clinically stable (including CD4 count >100 cells per µL and WHO HIV stage 1-3) were randomly assigned to: (1) fee for home delivery and monitoring of ART, including community ART initiation if needed; or (2) clinic-based ART (standard of care). The one-time fee for home delivery (ZAR 30, 60, and 90; equivalent to US$2, 4, 6) was tiered on the basis of participant income. The primary outcomes were recorded fee payment and acceptability assessed via questionnaire. The key virological secondary outcome was viral suppression with the difference between study groups assessed through robust Poisson regression including participants with viral load measured at exit (modified intention-to-treat analysis). This trial is registered on ClinicalTrials.gov (NCT04027153) and is complete, with analyses ongoing. FINDINGS: From Oct 7, 2019, to Jan 30, 2020, 162 participants were enrolled; 82 were randomly assigned to the fee for home delivery group and 80 to the clinic-based group, with similar characteristics at baseline. Overall, 87 (54%) participants were men, 101 (62%) were on ART, and 98 (60%) were unemployed. In the home delivery group, 40 (49%), 33 (40%), and nine (11%) participants qualified for the ZAR 30, 60, and 90 fee, respectively. Median follow-up was 47 weeks (IQR 43-50) with 96% retention. 80 (98%) participants paid the user fee, with high acceptability and willingness to pay. In the modified intention-to-treat analysis of 155 (96%) participants who completed follow-up, fee for home delivery and monitoring statistically significantly increased viral suppression from 74% to 88% overall (RR 1·21, 95% CI 1·02-1·42); and from 64% to 84% among men (1·31, 1·01-1·71). INTERPRETATION: Among South African adults with HIV, a fee for home delivery and monitoring of ART significantly increased viral suppression compared with clinic-based ART. Clients' paying a fee for home delivery and monitoring of ART was highly acceptable in the context of low income and high unemployment, and improved health outcomes as a result. Home ART delivery and monitoring, potentially with a user fee to offset costs, should be evaluated as a differentiated service delivery strategy to increase access to care. FUNDING: National Institutes of Mental Health.

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BACKGROUND: New strategies to increase measles and rubella vaccine coverage, particularly in low- and middle-income countries, are needed if elimination goals are to be achieved. With this regard, measles and rubella vaccine microneedle patches (MRV-MNP), in which the vaccine is embedded in dissolving microneedles, offer several potential advantages over subcutaneous delivery. These include ease of administration, increased thermostability, an absence of sharps waste, reduced overall costs and pain-free administration. This trial will provide the first clinical trial data on MRV-MNP use and the first clinical vaccine trial of MNP technology in children and infants. METHODS: This is a phase 1/2, randomized, active-controlled, double-blind, double-dummy, age de-escalation trial. Based on the defined eligibility criteria for the trial, including screening laboratory investigations, 45 adults [18-40 years] followed by 120 toddlers [15-18 months] and 120 infants [9-10 months] will be enrolled in series. To allow double-blinding, participants will receive either the MRV-MNP and a placebo (0.9% sodium chloride) subcutaneous (SC) injection or a placebo MNP and the MRV by SC injection (MRV-SC). Local and systemic adverse event data will be collected for 14 days following study product administration. Safety laboratories will be repeated on day 7 and, in the adult cohort alone, on day 14. Unsolicited adverse events including serious adverse events will be collected until the final study visit for each participant on day 180. Measles and rubella serum neutralizing antibodies will be measured at baseline, on day 42 and on day 180. Cohort progression will be dependent on review of the unblinded safety data by an independent data monitoring committee. DISCUSSION: This trial will provide the first clinical data on the use of a MNP to deliver the MRV and the first data on the use of MNPs in a paediatric population. It will guide future product development decisions for what may be a key technology for future measles and rubella elimination. TRIAL REGISTRATION: Pan-African Clinical Trials Registry 202008836432905 . CLINICALTRIALS: gov NCT04394689.

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BACKGROUND: Novel oncology treatment strategies increasingly use medicines with distinct but complementary mechanisms of action in combination or in close sequence. Payers, when confronted with higher total cost of providing combination regimens involving multiple therapies and usually longer treatment durations, are reluctant to reimburse them, particularly when they perceive the expected incremental benefits from adding a new medicine (the add-on) to a currently reimbursed medicine (the backbone) not to represent value for money to the health system. Nevertheless, depending on how value is attributed to the add-on versus the backbone, a clinically effective medicine used as part of a regimen that increases treatment duration might be found "not cost-effective at zero price." This phenomenon, signaling a policy problem not a pricing issue, first needs to be better understood before a generalizable and transparent solution can be presented. OBJECTIVE: This article sets out when this policy challenge arises and describes general principles that any proposed solution to the value attribution problem must satisfy. METHODS: We develop a simplified conceptual framework and use this to address 2 topics. The first is to understand the origin of problems posed by the current approach for attributing value in incremental cost-effectiveness analyses of combination regimens. The second is to discuss 2 new approaches in the literature designed to address the challenge. FINDINGS: We find that neither meets our criteria, meaning that further work is needed to resolve the issue. Finally, we briefly discuss the implications of relaxing the simplifying assumptions in our conceptual framework.

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Selected renal cells (SRCs), a renal epithelial cell-enriched platform, are being advanced as an autologous cell-based therapy for the treatment of chronic kidney disease. However, the mechanism underlying its renal reparative and restorative effects remains to be fully elucidated. In this study, we coupled knowledgebase data with empirical findings to demonstrate that genes differentially expressed by SRCs form interactomes within tubules and glomeruli and mediate a suite of renal developmental activities including epithelial cell differentiation, renal vasculature development, and glomerular and nephron development. In culture, SRCs form organoids which self-assemble into tubules in the presence of a scaffold. Implanted into the kidneys of subtotally nephrectomized rats, SRCs are associated with comma- and S-shaped body cell formation and glomerular development, and improvement in renal filtration indices and renal microarchitecture. These data suggest that SRCs harbor nephrogenic potential, which may explain, at least in part, their therapeutic activity.

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BACKGROUND: It is increasingly common for two or more treatments for cancer to be combined as a single regimen. Determining value and appropriate payment for such regimens can be challenging. This study discusses these challenges, and possible solutions. METHODS: Stakeholders from around the world attended a 2-day workshop, supported by a background paper. This study captures key outcomes from the discussion, but is not a consensus statement. RESULTS: Workshop attendees agreed that combining on-patent treatments can result in affordability and value for money challenges that delay or deny patient access to clinically effective treatments in many health systems. Options for addressing these challenges include: (i) Increasing the value of combination therapies through improved clinical development; (ii) Willingness to pay more for combinations than for single drugs offering similar benefit, or; (iii) Aligning the cost of constituent therapies with their value within a regimen. Workshop attendees felt that (i) and (iii) merited further discussion, whereas (ii) was unlikely to be justifiable. Views differed on the feasibility of (i). Key to (iii) would be systems allowing different prices to apply to different uses of a drug. CONCLUSIONS: Common ground was identified on immediate actions to improve access to combination regimens. These include an exploration of the legal challenges associated with price negotiations, and ensuring that pricing systems can support implementation of negotiated prices for specific uses. Improvements to clinical development and trial design should be pursued in the medium and longer term.

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Gut bacteria play a key role in initiating and maintaining the inflammatory process in the gut tissues of inflammatory bowel disease (IBD) patients, by supplying antigens or other stimulatory factors that trigger immune cell activation. Changes in the composition of the intestinal microbiota in IBD patients compared to that in healthy controls and a reduced diversity of intestinal microbial species are linked to the pathogenesis of IBD. Adherent invasive Escherichia coli (AIEC) has been linked to Crohn's disease (CD) patients, while diffusely adherent E. coli (DAEC) has been associated with ulcerative colitis (UC). Bacteriological analysis of intestinal biopsy specimens and fecal samples from IBD patients shows an increased number of E. coli strains belonging to the B2 phylogenetic group, which are typically known as extraintestinal pathogenic E. coli (ExPEC). Results from studies of both cell cultures and animal models reveal pathogenic features of these E. coli pathobionts, which may link them to IBD pathogenesis. This suggests that IBD-associated E. coli strains play a facilitative role during IBD flares. In this review, we explain IBD-associated E. coli and its role in IBD pathogenesis.

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PURPOSE: Few studies have examined the psychological and psychophysiological effects of recuperative music after exhaustive exercise. The main purpose of the present study was to examine the effects of two music conditions compared with a no-music control on psychological and psychophysiological recovery processes after exercise. METHODS: A randomized, fully counterbalanced, crossover design was used. Core affect, salivary cortisol, heart rate, and blood pressure were measured before exhaustive exercise, immediately after, and in 10-, 20-, and 30-min intervals during passive recovery (21 women and 21 men; 20.9 ± 1.7 yr) over three separate trials (slow, sedative music; fast, stimulative music; no-music control). The exercise task entailed incremental cycle ergometry performed at 75 rpm with an increase in intensity of 22.5 W·min at the end of each minute until exhaustion. Data were analyzed using mixed-model 3 (condition) × 4 (time) × 2 (gender) MANOVA/ANCOVA. RESULTS: The largest decline in affective arousal between active and passive recovery phases was evident in the slow, sedative condition (ηp = 0.50). Women had a more pronounced reduction in arousal than did men in the slow, sedative music condition. Heart rate measures showed that fast, stimulative music inhibited the return of heart rate toward resting levels (ηp = 0.06). Similarly, salivary cortisol levels tended to be lower in response to slow, sedative music (ηp = 0.11). There was a main effect of condition for affective valence indicating that the slow, sedative condition elicited more positive affective responses compared with the control and fast, stimulative conditions (ηp = 0.12). CONCLUSIONS: The present findings support the notion that slow, sedative music can expedite the recovery process immediately after strenuous exercise.

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A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus. Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis. In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda. By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.

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Ants create nests of a size that is tailored to the number of individuals in a nest via a self-organized process. It is not yet clear how they accomplish this. Deposition and evaporation of pheromones at the digging face has been hypothesised by Deneubourg and Franks (1995) and Buhl et al. (2005) to be part of the nest construction process, with models being presented to support this contention. This hypothesis was tested by allowing groups of 5 Acromyrmex lundi workers to choose between two excavation sites, one that was freshly exposed to digging and one where digging had ceased an hour previously. It was expected that if pheromones played a role in stimulating digging, then ants would show a preference for digging in the "fresh" sites rather than the "aged" sites where the putative digging pheromone had decayed. No significant difference in digging activity between "fresh" and "aged" sites was detected. It is therefore likely that, while digging pheromones may play other roles in other parts of the digging system, they do not play an important role in regulation of soil excavation at the digging face.

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AIM: Identification of mechanistic pathways for selected renal cell (SRC) therapeutic bioactivity in rodent models of chronic kidney disease. MATERIALS & METHODS: In vivo and in vitro functional bioassays applied to investigate regenerative outcomes associated with delivery of SRC to diseased rodent kidney. RESULTS: In vivo, SRC reduces chronic infiltration by monocytes/macrophages. SRC attenuates NF-κB and PAI-1 responses while simultaneously promoting host tubular cell expansion through trophic cues. In vitro, SRC-derived conditioned media attenuates TNF-α-induced NF-κB response, TGF-ß-mediated PAI-1 response and increases expression of transcripts associated with cell cycle regulation. Observed bioactive responses were from vesicle and nonvesicle-associated factors, including specific miRNAs. CONCLUSION: We identify a paracrine mechanism for SRC immunomodulatory and trophic cues on host renal tissues, catalyzing long-term functional benefits in vivo.

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Methodologies for the rigorous and quantitative evaluation of biological activity or potency are an essential aspect of the developmental pathway for all biologic product candidates. Such assays typically leverage key mechanistic pathways demonstrated to mediate observed therapeutic outcomes. Tissue engineered/regenerative medicine (TE/RM) therapeutics include cell based therapies as well as engineered tissues and neo-organs for which clarity regarding the mechanism or mechanisms of action may not be forthcoming. Here, we discuss how strategies for the development of potency assays for TE/RM product candidates may harness potential mechanisms of action or other therapeutically relevant bioactivity along with cell number and viability. As the pipeline for TE/RM product candidates expands through 2014 and beyond, the establishment of a defined framework for potency assays will facilitate successful translational outcomes.

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