Richard T. Eastman

Bio: Richard T. Eastman is an academic researcher from National Institutes of Health. The author has contributed to research in topics: Plasmodium falciparum & Medicine. The author has an hindex of 29, co-authored 66 publications receiving 3519 citations. Previous affiliations of Richard T. Eastman include Columbia University & University of Washington.

Remdesivir: A Review of Its Discovery and Development Leading to Emergency Use Authorization for Treatment of COVID-19

Abstract: The global pandemic of SARS-CoV-2, the causative viral pathogen of COVID-19, has driven the biomedical community to action—to uncover and develop antiviral interventions. One potential therapeutic ...

Artemisinin-based combination therapies: a vital tool in efforts to eliminate malaria

Abstract: Plasmodium falciparum resistance to chloroquine and sulphadoxine-pyrimethamine has led to the recent adoption of artemisinin-based combination therapies (ACTs) as the first line of treatment against malaria. ACTs comprise semisynthetic artemisinin derivatives paired with distinct chemical classes of longer acting drugs. These artemisinins are exceptionally potent against the pathogenic asexual blood stages of Plasmodium parasites and also act on the transmissible sexual stages. These combinations increase the rates of clinical and parasitological cures and decrease the selection pressure for the emergence of antimalarial resistance. This Review article discusses our current knowledge about the mode of action of ACTs, their pharmacological properties and the proposed mechanisms of drug resistance.

Quantitative assessment of Plasmodium falciparum sexual development reveals potent transmission-blocking activity by methylene blue

Abstract: Clinical studies and mathematical models predict that, to achieve malaria elimination, combination therapies will need to incorporate drugs that block the transmission of Plasmodium falciparum sexual stage parasites to mosquito vectors. Efforts to measure the activity of existing antimalarials on intraerythrocytic sexual stage gametocytes and identify transmission-blocking agents have, until now, been hindered by a lack of quantitative assays. Here, we report an experimental system using P. falciparum lines that stably express gametocyte-specific GFP-luciferase reporters, which enable the assessment of dose- and time-dependent drug action on gametocyte maturation and transmission. These studies reveal activity of the first-line antimalarial dihydroartemisinin and the partner drugs lumefantrine and pyronaridine against early gametocyte stages, along with moderate inhibition of mature gametocyte transmission to Anopheles mosquitoes. The other partner agents monodesethyl-amodiaquine and piperaquine showed activity only against immature gametocytes. Our data also identify methylene blue as a potent inhibitor of gametocyte development across all stages. This thiazine dye almost fully abolishes P. falciparum transmission to mosquitoes at concentrations readily achievable in humans, highlighting the potential of this chemical class to reduce the spread of malaria.

Symptoms of Sensory Neuropathy in Adults with NIDDM in the U.S. Population

Abstract: OBJECTIVE To ascertain the prevalence and determinants of sensory neuropathy symptoms through structured interview of a representative sample of people with diabetes in the U.S. population. RESEARCH DESIGN AND METHODS The 1989 National Health Interview Survey consisted of a representative sample of 84,572 persons in the U.S. ≥ 18 yr of age. A household respondent identified all people in the household believed to have diabetes ( n = 2829). Subjects who could not be personally interviewed ( n = 129) and individuals who stated they did not have diabetes ( n = 295) were excluded. A detailed questionnaire was administered to 99.3% of the remaining 2405 subjects. Questions on symptoms of sensory neuropathy included whether during the past 3 mo the subjects had experienced numbness or loss of feeling, pain or tingling, or decreased ability to feel hot or cold. The neuropathy questions were also administered to a representative sample of 20,037 subjects who were not known to have diabetes. RESULTS Prevalence of symptoms of sensory neuropathy was 30.2% among people with IDDM. This prevalence was 36.0% for men with NIDDM and 39.8% for women with NIDDM, compared with 9.8 and 11.8% for nondiabetic men and women, respectively. In logistic regression, factors independently related to symptoms of sensory neuropathy in people with NIDDM included duration of diabetes, hypertension, hyperglycemia, and glycosuria. Long duration of NIDDM (>20 yr) was associated with a twofold increased risk of symptoms of sensory neuropathy compared with those with 0-4 yr of diabetes. Hypertension was associated with a 60% higher likelihood of symptoms. Diabetic individuals whose blood glucose was high all or most of the time or whose urine tests showed glucose all of the time were > 2 times as likely to have symptoms of sensory neuropathy than those who did not report hyperglycemia or glycosuria. Age, sex, ethnicity, cigarette smoking, and height were not determinants of sensory neuropathy. CONCLUSIONS Symptoms of sensory neuropathy affect 30–40% of diabetic patients in the U.S. Men and women are affected equally. Prevalence of these symptoms increases with longer duration of diabetes; hypertension and hyperglycemia predispose to symptoms of sensory neuropathy.

Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): prospective observational study

Abstract: Objective: To determine the relation between exposure to glycaemia over time and the risk of macrovascular or microvascular complications in patients with type 2 diabetes. Design: Prospective observational study. Setting: 23 hospital based clinics in England, Scotland, and Northern Ireland. Participants: 4585 white, Asian Indian, and Afro-Caribbean UKPDS patients, whether randomised or not to treatment, were included in analyses of incidence; of these, 3642 were included in analyses of relative risk. Outcome measures: Primary predefined aggregate clinical outcomes: any end point or deaths related to diabetes and all cause mortality. Secondary aggregate outcomes: myocardial infarction, stroke, amputation (including death from peripheral vascular disease), and microvascular disease (predominantly retinal photo-coagulation). Single end points: non-fatal heart failure and cataract extraction. Risk reduction associated with a 1% reduction in updated mean HbA 1c adjusted for possible confounders at diagnosis of diabetes. Results: The incidence of clinical complications was significantly associated with glycaemia. Each 1% reduction in updated mean HbA 1c was associated with reductions in risk of 21% for any end point related to diabetes (95% confidence interval 17% to 24%, P Conclusions: In patients with type 2 diabetes the risk of diabetic complications was strongly associated with previous hyperglycaemia. Any reduction in HbA 1c is likely to reduce the risk of complications, with the lowest risk being in those with HbA 1c values in the normal range (

Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study

Abstract: Summary Background Since December, 2019, Wuhan, China, has experienced an outbreak of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Epidemiological and clinical characteristics of patients with COVID-19 have been reported but risk factors for mortality and a detailed clinical course of illness, including viral shedding, have not been well described. Methods In this retrospective, multicentre cohort study, we included all adult inpatients (≥18 years old) with laboratory-confirmed COVID-19 from Jinyintan Hospital and Wuhan Pulmonary Hospital (Wuhan, China) who had been discharged or had died by Jan 31, 2020. Demographic, clinical, treatment, and laboratory data, including serial samples for viral RNA detection, were extracted from electronic medical records and compared between survivors and non-survivors. We used univariable and multivariable logistic regression methods to explore the risk factors associated with in-hospital death. Findings 191 patients (135 from Jinyintan Hospital and 56 from Wuhan Pulmonary Hospital) were included in this study, of whom 137 were discharged and 54 died in hospital. 91 (48%) patients had a comorbidity, with hypertension being the most common (58 [30%] patients), followed by diabetes (36 [19%] patients) and coronary heart disease (15 [8%] patients). Multivariable regression showed increasing odds of in-hospital death associated with older age (odds ratio 1·10, 95% CI 1·03–1·17, per year increase; p=0·0043), higher Sequential Organ Failure Assessment (SOFA) score (5·65, 2·61–12·23; p Interpretation The potential risk factors of older age, high SOFA score, and d-dimer greater than 1 μg/mL could help clinicians to identify patients with poor prognosis at an early stage. Prolonged viral shedding provides the rationale for a strategy of isolation of infected patients and optimal antiviral interventions in the future. Funding Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences; National Science Grant for Distinguished Young Scholars; National Key Research and Development Program of China; The Beijing Science and Technology Project; and Major Projects of National Science and Technology on New Drug Creation and Development.

Association of systolic blood pressure with macrovascular and microvascular complications of type 2 diabetes (UKPDS 36): prospective observational study

Abstract: OBJECTIVE: To determine the relation between systolic blood pressure over time and the risk of macrovascular or microvascular complications in patients with type 2 diabetes. DESIGN: Prospective observational study. SETTING: 23 hospital based clinics in England, Scotland, and Northern Ireland. PARTICIPANTS: 4801 white, Asian Indian, and Afro-Caribbean UKPDS patients, whether randomised or not to treatment, were included in analyses of incidence; of these, 3642 were included in analyses of relative risk. OUTCOME MEASURES: Primary predefined aggregate clinical outcomes: any complications or deaths related to diabetes and all cause mortality. Secondary aggregate outcomes: myocardial infarction, stroke, lower extremity amputation (including death from peripheral vascular disease), and microvascular disease (predominantly retinal photocoagulation). Single end points: non-fatal heart failure and cataract extraction. Risk reduction associated with a 10 mm Hg decrease in updated mean systolic blood pressure adjusted for specific confounders. RESULTS: The incidence of clinical complications was significantly associated with systolic blood pressure, except for cataract extraction. Each 10 mm Hg decrease in updated mean systolic blood pressure was associated with reductions in risk of 12% for any complication related to diabetes (95% confidence interval 10% to 14%, P<0.0001), 15% for deaths related to diabetes (12% to 18%, P<0.0001), 11% for myocardial infarction (7% to 14%, P<0.0001), and 13% for microvascular complications (10% to 16%, P<0.0001). No threshold of risk was observed for any end point. CONCLUSIONS: In patients with type 2 diabetes the risk of diabetic complications was strongly associated with raised blood pressure. Any reduction in blood pressure is likely to reduce the risk of complications, with the lowest risk being in those with systolic blood pressure less than 120 mm Hg.