Improving access to essential medicines

Equitable access to essential medicines is crucial to improve population health and support economic growth. A diverse range of access strategies have been implemented to target barriers across the different dimensions of access. This thesis contributes to the evidence on access to medicines strategies, focusing largely on international coordination and policy. First, I conduct a scoping review to identify strategies instigated by different stakeholders to improve access across a broad range of therapeutic areas and country contexts (Chapter 2). The remainder of the thesis seeks to address some of the literature gaps identified in this review. I explore inequalities and inequities in WHO essential medicines compared with need (Chapter 3). I find that despite inequalities with listing concentrated in high burden disease areas (pro-high burden inequalities), inequities remain when assessing listing proportionally to need. I observe differences over time, across broad disease groups, and across country income levels. I highlight disease areas in which attention is required to either list or develop essential medicines. In Chapter 4, I examine the impact of voluntary licensing and patent pooling for hepatitis C on access to treatment. I find evidence that licensing increases treatment rate beyond what would be expected in its absence and find that the impact of licensing increases with time. This evidence supports the careful expansion of the Medicines Patent Pool to improve access in other therapeutic areas. Finally (Chapter 5), to explore the issue of rational use, I examine antibiotic consumption in reference to the WHO AWaRe (Access, Watch, Reserve) classification for optimising the use of antibiotics. Overall and per capita consumption varied across the eight high-income countries studied, but most countries were meeting the associated Access target. The results from this thesis can help inform appropriate access strategies to improve equitable access to essential medicines worldwide.Open Acces

Optimizing the Ethiopian health extension programme: strategies to address workforce challenges

The Health Extension Programme (HEP) serves as a flagship programme in the delivery of primary health care (PHC) in Ethiopia. However, its implementation has faced various health system barriers. By laying out transformative strategies, the HEP Optimization Roadmap (2020–2035) presents an opportunity to restructure and standardize the programme’s service delivery approach to ensure long-term sustainability and impact

Initial supplementary dose of Dolutegravir in second-line antiretroviral therapy: a noncomparative, double-blind, randomized placebo-controlled trial

BACKGROUND: Dolutegravir concentrations are reduced by efavirenz induction effect necessitating twice-daily dolutegravir dosing when coadministered. Efavirenz induction persists for several weeks after stopping, which could potentially select for dolutegravir resistance if switching occurred with unsuppressed human immunodeficiency virus type 1 (HIV-1) RNA levels and standard dolutegravir dosing. We evaluated the need for a lead-in supplementary dolutegravir dose in adults failing first-line tenofovir-emtricitabine-efavirenz (TEE). METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 2 trial in Khayelitsha, South Africa. Eligible patients had virologic failure (2 consecutive HIV-1 RNA ≥1000 copies/mL) on first-line TEE. Participants were randomly assigned (1:1) to switch to tenofovir-lamivudine-dolutegravir (TLD) with a supplementary 50 mg dolutegravir dose or placebo taken 12 hours later for 14 days. Primary outcome was proportion with HIV-1 RNA <50 copies/mL at week 24. This study was not powered to compare arms. RESULTS: One hundred thirty participants were randomized (65 to each arm). Median baseline HIV-1 RNA was 4.0 log10 copies/mL and 76% had baseline resistance to both tenofovir and lamivudine. One participant died and 2 were lost to follow-up. At week 24, 55 of 64 (86% [95% confidence interval {CI}: 75%-93%]) in the supplementary dolutegravir arm and 53 of 65 (82% [95% CI: 70%-90%]) in the placebo arm had HIV-1 RNA <50 copies/mL. Grade 3 or 4 adverse events were similar in frequency between arms. None of 6 participants (3 in each arm) eligible for resistance testing by 24 weeks developed dolutegravir resistance. CONCLUSIONS: Our findings do not support the need for initial dolutegravir dose adjustment in patients switching to TLD who failed first-line TEE. CLINICAL TRIALS REGISTRATION: NCT03991013

Standard-dose versus double-dose dolutegravir in HIV-associated tuberculosis in South Africa (RADIANT-TB): a phase 2, non-comparative, randomised controlled trial

Background: The drug–drug interaction between rifampicin and dolutegravir can be overcome by supplemental dolutegravir dosing, which is difficult to implement in high-burden settings. We aimed to test whether virological outcomes with standard-dose dolutegravir-based antiretroviral therapy (ART) are acceptable in people with HIV on rifampicin-based antituberculosis therapy. Methods: RADIANT-TB was a phase 2b, randomised, double-blind, non-comparative, placebo-controlled trial at a single site in Khayelitsha, Cape Town, South Africa. Participants were older than 18 years of age, with plasma HIV-1 RNA greater than 1000 copies per mL, CD4 count greater than 100 cells per μL, ART-naive or first-line ART interrupted, and on rifampicin-based antituberculosis therapy for less than 3 months. By use of permuted block (block size of 6) randomisation, participants were assigned (1:1) to receive either tenofovir disoproxil fumarate, lamivudine, and dolutegravir plus supplemental 50 mg dolutegravir 12 h later or tenofovir disoproxil fumarate, lamivudine, and dolutegravir plus matched placebo 12 h later. Participants received standard antituberculosis therapy (rifampicin, isoniazid, pyrazinamide, and ethambutol for the first 2 months followed by isoniazid and rifampicin for 4 months). The primary outcome was the proportion of participants with virological suppression (HIV-1 RNA <50 copies per mL) at week 24 analysed in the modified intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT03851588. Findings: Between Nov 28, 2019, and July 23, 2021, 108 participants (38 female, median age 35 years [IQR 31–40]) were randomly assigned to supplemental dolutegravir (n=53) or placebo (n=55). Median baseline CD4 count was 188 cells per μL (IQR 145–316) and median HIV-1 RNA was 5·2 log10 copies per mL (4·6–5·7). At week 24, 43 (83%, 95% CI 70–92) of 52 participants in the supplemental dolutegravir arm and 44 (83%, 95% CI 70–92) of 53 participants in the placebo arm had virological suppression. No treatment-emergent dolutegravir resistance mutations were detected up to week 48 in the 19 participants with study-defined virological failure. Grade 3 and 4 adverse events were similarly distributed between the study arms. The most frequent grade 3 and 4 adverse events were weight loss (4/108 [4%]), insomnia (3/108 [3%]), and pneumonia (3/108 [3%]). Interpretation: Our findings suggest that twice-daily dolutegravir might be unnecessary in people with HIV-associated tuberculosis. Funding: Wellcome Trust

Prevalence of hepatitis B and C infection in persons living with HIV enrolled in care in Rwanda

BACKGROUND: Hepatitis B (HBV) and C (HCV) are important causes of morbidity and mortality in people living with human immunodeficiency virus (HIV). The burden of these co-infections in sub-Saharan Africa is still unclear. We estimated the prevalence of the hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCVAb) among HIV-infected individuals in Rwanda and identified factors associated with infection. METHODS: Between January 2016 and June 2016, we performed systematic screening for HBsAg and HCVAb among HIV-positive individuals enrolled at public and private HIV facilities across Rwanda. Results were analyzed to determine marker prevalence and variability by demographic factors. RESULTS: Overall, among 117,258 individuals tested, the prevalence of HBsAg and HCVAb was 4.3% (95% confidence interval [CI] (4.2-4.4) and 4.6% (95% CI 4.5-4.7) respectively; 182 (0.2%) HIV+ individuals were co-infected with HBsAg and HCVAb. Prevalence was higher in males (HBsAg, 5.4% [5.1-5.6] vs. 3.7% [3.5-3.8]; HCVAb, 5.0% [4.8-5.2] vs. 4.4% [4.3-4.6]) and increased with age; HCVAb prevalence was significantly higher in people aged ≥65 years (17.8% [16.4-19.2]). Prevalence varied geographically. CONCLUSION: HBV and HCV co-infections are common among HIV-infected individuals in Rwanda. It is important that viral hepatitis prevention and treatment activities are scaled-up to control further transmission and reduce the burden in this population. Particular efforts should be made to conduct targeted screening of males and the older population. Further assessment is required to determine rates of HBV and HCV chronicity among HIV-infected individuals and identify effective strategies to link individuals to care and treatment

Increased dolutegravir peak concentrations in people living with HIV aged 60 and over and analysis of sleep quality and cognition

Background Demographic data show an increasingly aging HIV population worldwide. Recent concerns over dolutegravir-related neuropsychiatric toxicity have emerged, particularly amongst older HIV patients. We describe the pharmacokinetics (PK) of dolutegravir (DTG) 50mg once daily in people living with HIV (PLWH) aged 60 and older. Additionally, to address the call for prospective neuropsychiatric toxicodynamic data, we evaluate changes in sleep quality and cognitive function after switching to abacavir (ABC)/lamivudine (3TC)/DTG, over 6 months in this population. Methods PLWH aged≥60years with HIV-RNA<50copies/mL on any non-DTG based antiretroviral combination were switched to ABC/3TC/DTG. On day 28, 24-hour PK sampling was undertaken. Steady-state PK parameters were compared to a published historical control population aged≤50years. Six validated sleep questionnaires and neurocognitive (Cogstate®) testing were administered pre-switch and over 180 days (NCT02509195). Results Forty-three participants were enrolled; 40 completed the PK phase. Overall, five discontinued (two due adverse events, both sleep related, 4.6%). DTG maximum concentration (Cmax) was significantly higher in patients≥60 versus controls (GM 4246ng/mL versus 3402ng/mL, p=0.005). In those who completed day 180 (n=38), sleep impairment was higher at day 28 (PSQI median global score 5.0 versus 6.0 p=0.02) but not at day 90 or 180. Insomnia, daytime function, fatigue test scores did not change statistically over time. Conclusion DTG Cmax was significantly higher in older PLWH. Our data provides clinicians with key information on the safety of prescribing DTG in older PLWH

Progress towards antibiotic use targets in eight high-income countries

OBJECTIVE: To compare antibiotic sales in eight high-income countries using the 2019 World Health Organization (WHO) Access, Watch and Reserve (AWaRe) classification and the target of 60% consumption of Access category antibiotics. METHODS: We analysed data from a commercial database of sales of systemic antibiotics in France, Germany, Italy, Japan, Spain, Switzerland, United Kingdom of Great Britain and Northern Ireland, and United States of America over the years 2013-2018. We classified antibiotics according to the 2019 AWaRe categories: Access, Watch, Reserve and Not Recommended. We measured antibiotic sales per capita in standard units (SU) per capita and calculated Access group sales as a percentage of total antibiotic sales. FINDINGS: In 2018, per capita antibiotic sales ranged from 7.4 SU (Switzerland) to 20.0 SU (France); median sales of Access group antibiotics were 10.9 SU per capita (range: 3.5-15.0). Per capita sales declined moderately over 2013-2018. The median percentage of Access group antibiotics was 68% (range: 22-77 %); the Access group proportion increased in most countries between 2013 and 2018. Five countries exceeded the 60% target; two countries narrowly missed it (\u3e 55% in Germany and Italy). Sales of Access antibiotics in Japan were low (22%), driven by relatively high sales of oral cephalosporins and macrolides. CONCLUSION: We have identified changes to prescribing that could allow countries to achieve the WHO target. The 60% Access group target provides a framework to inform national antibiotic policies and could be complemented by absolute measures and more ambitious values in specific settings

Randomized clinical trial of nitazoxanide or sofosbuvir/daclatasvir for the prevention of SARS-CoV-2 infection

BACKGROUND: The COVER trial evaluated whether nitazoxanide or sofosbuvir/daclatasvir could lower the risk of SARS-CoV-2 infection. Nitazoxanide was selected given its favourable pharmacokinetics and in vitro antiviral effects against SARS-CoV-2. Sofosbuvir/daclatasvir had shown favourable results in early clinical trials. METHODS: In this clinical trial in Johannesburg, South Africa, healthcare workers and others at high risk of infection were randomized to 24 weeks of either nitazoxanide or sofosbuvir/daclatasvir as prevention, or standard prevention advice only. Participants were evaluated every 4 weeks for COVID-19 symptoms and had antibody and PCR testing. The primary endpoint was positive SARS-CoV-2 PCR and/or serology ≥7 days after randomization, regardless of symptoms. A Poisson regression model was used to estimate the incidence rate ratios of confirmed SARS-CoV-2 between each experimental arm and control. RESULTS: Between December 2020 and January 2022, 828 participants were enrolled. COVID-19 infections were confirmed in 100 participants on nitazoxanide (2234 per 1000 person-years; 95% CI 1837-2718), 87 on sofosbuvir/daclatasvir (2125 per 1000 person-years; 95% CI 1722-2622) and 111 in the control arm (1849 per 1000 person-years; 95% CI 1535-2227). There were no significant differences in the primary endpoint between the treatment arms, and the results met the criteria for futility. In the safety analysis, the frequency of grade 3 or 4 adverse events was low and similar across arms. CONCLUSIONS: In this randomized trial, nitazoxanide and sofosbuvir/daclatasvir had no significant preventative effect on infection with SARS-CoV-2 among healthcare workers and others at high risk of infection

Minimum Target Prices for Production of Direct-Acting Antivirals and Associated Diagnostics to Combat Hepatitis C Virus

Combinations of direct-acting antivirals (DAAs) can cure hepatitis C virus (HCV) in the majority of treatment-na€ ıve patients. Mass treatment programs to cure HCV in developing countries are only feasible if the costs of treatment and laboratory diagnostics are very low. This analysis aimed to estimate minimum costs of DAA treatment and associated diagnostic monitoring. Clinical trials of HCV DAAs were reviewed to identify combinations with consistently high rates of sustained virological response across hepatitis C genotypes. For each DAA, molecular structures, doses, treatment duration, and components of retrosynthesis were used to estimate costs of large-scale, generic production. Manufacturing costs per gram of DAA were based upon treating at least 5 million patients per year and a 40% margin for formulation. Costs of diagnostic support were estimated based on published minimum prices of genotyping, HCV antigen tests plus full blood count/clinical chemistry tests. Predicted minimum costs for 12-week courses of combination DAAs with the most consistent efficacy results were: US$122 per person for sofosbuvir1daclatasvir

Phase 3 evaluation of an innovative simple molecular test for the diagnosis of malaria in different endemic and health settings in sub-Saharan Africa (DIAGMAL)

Background Rapid Diagnostic Tests (RDTs) have become the cornerstone for the management of malaria in many endemic settings, but their use is constrained for several reasons: (i) persistent malaria antigen (histidine-rich protein 2; HRP2) leading to false positive test results; (ii) hrp2 deletions leading to false negative PfHRP2 results; and (iii) limited sensitivity with a detection threshold of around 100 parasites/μl blood (pLDH- and HRP2-based) leading to false negative tests. Microscopy is still the gold standard for malaria diagnosis, and allows for species determination and quantitation, but requires trained microscopists, maintained microscopes and has detection limit issues. Consequently, there is a pressing need to develop and evaluate more sensitive and accurate diagnostic tests. To address this need we have developed a direct on blood mini PCR-NALFIA test that combines the benefits of molecular biology with low infrastructural requirements and extensive training. Methods This is a Phase 3 diagnostic evaluation in 5 African countries. Study sites (Sudan, Ethiopia, Burkina, Kenya and Namibia) were selected to ensure wide geographical coverage of Africa and to address various malaria epidemiological contexts ranging from high transmission to near elimination settings with different clinical scenarios and diagnostic challenges. Study participants will be enrolled at the study health facilities after obtaining written informed consent. Diagnostic accuracy will be assessed following the WHO/TDR guidelines for the evaluation of diagnostics and reported according to STARD principles. Due to the lack of a 100% specific and sensitive standard diagnostic test for malaria, the sensitivity and specificity of the new test will be compared to the available diagnostic practices in place at the selected sites and to quantitative PCR as the reference test. Discussion This phase 3 study is designed to validate the clinical performance and feasibility of implementing a new diagnostic tool for the detection of malaria in real clinical settings. If successful, the proposed technology will improve the diagnosis of malaria. Enrolment started in November 2022 (Kenya) with assessment of long term outcome to be completed by 2023 at all recruitment sites