Potential pharmacokinetic interactions with concurrent use of herbal medicines and a ritonavir-boosted COVID-19 protease inhibitor in low and middle-income countries.

The COVID-19 pandemic sparked the development of novel anti-viral drugs that have shown to be effective in reducing both fatality and hospitalization rates in patients with elevated risk for COVID-19 related morbidity or mortality. Currently, nirmatrelvir/ritonavir (Paxlovid™) fixed-dose combination is recommended by the World Health Organization for treatment of COVID-19. The ritonavir component is an inhibitor of cytochrome P450 (CYP) 3A, which is used in this combination to achieve needed therapeutic concentrations of nirmatrelvir. Because of the critical pharmacokinetic effect of this mechanism of action for Paxlovid™, co-administration with needed medications that inhibit or induce CYP3A is contraindicated, reflecting concern for interactions with the potential to alter the efficacy or safety of co-administered drugs that are also metabolized by CYP3A. Some herbal medicines are known to interact with drug metabolizing enzymes and transporters, including but not limited to inhibition or induction of CYP3A and P-glycoprotein. As access to these COVID-19 medications has increased in low- and middle-income countries (LMICs), understanding the potential for herb-drug interactions within these regions is important. Many studies have evaluated the utility of herbal medicines for COVID-19 treatments, yet information on potential herb-drug interactions involving Paxlovid™, specifically with herbal medicines commonly used in LMICs, is lacking. This review presents data on regionally-relevant herbal medicine use (particularly those promoted as treatments for COVID-19) and mechanism of action data on herbal medicines to highlight the potential for herbal medicine interaction Herb-drug interaction mediated by ritonavir-boosted antiviral protease inhibitors This work highlights potential areas for future experimental studies and data collection, identifies herbal medicines for inclusion in future listings of regionally diverse potential HDIs and underscores areas for LMIC-focused provider-patient communication. This overview is presented to support governments and health protection entities as they prepare for an increase of availability and use of Paxlovid™.

Utility of HIV support groups in advancing implementation research in resource-limited settings: experiences from an urban-setting HIV support group in Zimbabwe.

Support groups for people living with the Human Immunodeficiency Virus (HIV) have continued to evolve since their emergence over two decades ago. In addition to providing HIV education and fostering psychosocial support, recent efforts have shifted the focus to socio-economic activities and retention in care. The sense of urgency to adopt new treatment and prevention strategies in sub-Saharan Africa necessitates greater engagement of established HIV care programs, especially among researchers seeking to conduct implementation research, promote prevention strategies and optimize treatment as prevention. To maximize the utility of support groups in doing so, efforts to create an organized, collaborative framework should be considered. This paper aims to describe the process of refocusing an adult HIV peer-support group and illustrate how a structured program was strengthened to sustain implementation research in resource-limited settings, while promoting patient recruitment and retention. A multidisciplinary team of scientists supporting an HIV peer-support group spearheaded the implementation process that authored the successes, challenges and lessons documented over eight years. Psychosocial support, nutrition care and support, adherence education and income generating projects were the main interventions employed. The initiative resulted in seven peer-reviewed publications, submission of 23 scientific abstracts, scientific dissemination at 12 international conferences. Eleven research studies and 16 income generating projects were successfully conducted over eight years. More than 900 patients participated in peer-support group activities every month and 400 were engaged in income generating activities. This multidisciplinary structured program was valuable in the retention and recruitment of patients for implementation research and benefits extended to psychosocial support, microeconomic projects, and improved nutrition. The support group contributed to strengthening implementation research through providing a platform for identification of research priorities, patient recruitment and retention in studies and dissemination of research findings.

Perceptions of diabetes patients and their caregivers regarding access to medicine in a severely constrained health system: A qualitative study in Harare, Zimbabwe.

Nearly half of all sub-Saharan African countries lack operational Diabetes Mellitus policies. This represents an opportunity to build reliable evidence to underpin such policies when they are eventually developed. Representing the interests of those with the experience of living with the condition in national diabetes policies is important, particularly the interests regarding medicine access, a key pillar in diabetes management. One way to achieve this representation is to publish patient perceptions. Patient perspectives are especially valuable in the context of diabetes in Sub-Saharan Africa, where much of the empirical work has focused on clinical and epidemiological questions. We therefore captured the challenges and suggestions around medicine access articulated by a population of diabetes patients and their caregivers. This was a qualitative interpretivist study based on data from focus group discussions with adult diabetes patients and their caregivers. Eight FGDs of 4-13 participants each whose duration averaged 13.35 minutes were conducted. Participants were recruited from diabetes outpatient clinics at two health facilities in Harare. One site was Parirenyatwa Hospital, the largest public referral and teaching hospital in Zimbabwe. The other was a private for-profit facility. Ethics approval was granted by the Joint Research Ethics Committee for University of Zimbabwe College of Health Sciences and the Parirenyatwa Group of Hospitals (Ref: JREC 295/18). Diabetes patients and their caregivers are interested in affordable access to medicines of acceptable form and quality with minimum effort. Yet, they often find themselves privileging one dimension of access over another e.g. prioritising affordability over acceptability. Based on participants' articulations, a sound diabetes policy should: 1. provide for financial and consumer protections, 2. regulate healthcare business practices and medicine prices, 3. provide for a responsive health workforce attentive to patient problems, 4. accord the same importance to diabetes that is accorded to communicable diseases, 5. decentralize diabetes management to lower levels of care, 6. limit wastage, corruption, bad macro-financial governance and a lack of transparency about how funding for health is used, and 7. provide support to strengthen patients' and caregivers' psychosocial networks. A diabetes policy acceptable to patients is one infused with principles of good governance, fairness, inclusiveness and humanity; characterised by: financial protection and price regulation, consumer protection, equity in the attention accorded to different diseases, decentralized service delivery, inclusion of patient voice in political decision-making, a responsive compassionate health workforce, psychosocial support for patients and their caregivers and allocative efficiency and transparency in public expenditure.

Two decades (1998 to 2018) of collaborative human immunodeficiency virus clinical pharmacology capacity building in a resource constrained setting.

While important advances have been made in the prevention and treatment of Human Immunodeficiency Virus (HIV) infection, limited expertise and resource constraints to effectively manage rollout of HIV programs often contribute to poor treatment outcomes in Sub-Saharan Africa. In 1998, the University of Zimbabwe (UZ) and the University at Buffalo, State University of New York (UB), developed a collaborative clinical pharmacology capacity building program in Zimbabwe to train the next generation of HIV researchers and support rollout of the national HIV program. The collaboration was funded by research and training grants that were competitively acquired through United States of America government funding mechanisms, between 1998 and 2016. Thirty-eight research fellows were trained and a specialty clinical pharmacology laboratory was established during this period. Knowledge and skills transfer were achieved through faculty and student exchange visits. Scientific dissemination output included sixty-two scholarly publications that influenced three national policies and provided development of guidelines for strategic leadership for an HIV infection-patient adherence support group. The clinical pharmacology capacity building program trained fellows that were subsequently incorporated into the national technical working group at the Ministry of Health and Child Care, who are responsible for optimizing HIV treatment guidelines in Zimbabwe. Despite serious economic challenges, consistent collaboration between UZ and UB strengthened UZ faculty scholarly capacity, retention of HIV clinical research workforce was achieved, and the program made additional contributions toward optimization of antiretroviral therapy in Zimbabwe.

Proximal renal tubular function in HIV-infected children on tenofovir disoproxil fumarate for treatment of HIV infection at two tertiary hospitals in Harare, Zimbabwe.

BACKGROUND: Renal abnormalities in HIV infected children may be due to the HIV infection or treatment among other factors. Tenofovir disoproxil fumarate (TDF) is associated with proximal renal tubular dysfunction, proteinuria and decrease in glomerular function. Studies in developed countries have shown variable prevalence of proximal renal tubular dysfunction in children on TDF. There are no known studies in developing countries, including Zimbabwe, documenting the proximal tubular function in HIV infected children on TDF. The aim of this study was to assess renal and proximal renal tubular function in HIV infected children receiving TDF and determine factors associated with proximal tubular dysfunction. METHODS: A descriptive cross-sectional study was conducted in HIV infected patients below 18 years of age attending outpatient clinics at two tertiary hospitals in Harare, who received a TDF-containing antiretroviral regimen for at least six months. Dipstick protein and glucose, serum and urine phosphate and creatinine levels were measured. Fractional excretion of phosphate was calculated. Estimated glomerular filtration rate (eGFR) was calculated using the Schwartz formula. Tubular dysfunction was defined by at least two of the following characteristics: normoglycaemic glycosuria, hypophosphatemia and fractional excretion of phosphate > 18%. FINDINGS: One hundred and ninety-eight children below 18 years of age were recruited over a period of six months. The prevalence of tubular dysfunction was 0.5%. Normoglycaemic glycosuria occurred in 1 (0.5%), fractional excretion of phosphate >18% in 4 (2%), and hypophosphatemia in 22 [11.1%] patients. Severe stunting was associated with increased risk of hypophosphatemia (OR 9.31 CI (1.18, 80.68) p = 0.03). Reduction in estimated glomerular filtration rate (eGFR) < 90ml/min/1.73m2 and proteinuria was evident in 35.9% and 32.8% of children, respectively. Concurrent TDF and HIV-1 protease inhibitor-based regimen was the only independent factor associated with reduction in GFR (OR 4.43 CI (1.32; 4.89) p = 0.016). CONCLUSION: Tubular dysfunction was uncommon in Zimbabwean children on a TDF-based ART regimen. Hypophosphatemia, proteinuria and reduction in eGFR were common. Reassessing renal function using more sensitive biomarkers is needed to examine the long-term tolerance of TDF.

Perspectives on oral pre-exposure prophylaxis use amongst female sex workers in Harare, Zimbabwe.

BACKGROUND: Pre-exposure prophylaxis (PrEP) could provide protection from human immunodeficiency virus (HIV) infection in sexually active persons at risk. Limited data are available in Zimbabwe with regard to the perceptions about PrEP amongst female sex workers (FSWs). OBJECTIVES: The aim of this study was to evaluate the knowledge levels of oral PrEP and the likelihood of its use amongst FSWs. METHOD: This was a cross-sectional study in the peri-urban areas of Harare, Zimbabwe. Human immunodeficiency virus-negative FSWs were interviewed to assess their awareness of and likelihood to use PrEP. The relative importance index was used to evaluate the levels of knowledge and the likelihood of, and barriers to, PrEP use. A set of 10 questions was designed and validated that evaluated participants' understanding of PrEP. A bivariate logistic regression model was utilised to identify predictors of PrEP use. RESULTS: A total of 131 FSWs with a median age of 25 years (interquartile range: 21-31) participated in this study. Of the 71 (54%) FSWs who had heard about PrEP, 46 (35%) participants had adequate knowledge of its use. A total of 102 (78%) participants revealed that they would be willing to continuously use PrEP if it was provided free of cost. Increasing age of the participants was associated with an increase in the likelihood of using PrEP (r = 0.0033, p = 0.038). More knowledge about PrEP increased the likelihood of its use (r = 0.21, p = 0.0153). This likelihood increased amongst participants with an unprotected sexual intercourse encounter in the preceding 3 months (r = 0.0448, p = 0.026). CONCLUSION: Knowledge of PrEP amongst FSWs was low. To increase the uptake of PrEP, there is a need to further sensitise FSWs about this intervention. Programmes should also promote awareness training in FSW subgroups that are less likely to use PrEP.

An analysis of hospital pharmacy practice in six countries of sub-Saharan Africa based on the International Pharmaceutical Federation Basel Statements on the future of hospital pharmacy.

OBJECTIVES: The objective of this study was to update the self-assessment tool and to evaluate current hospital pharmacy practices in six sub-Saharan African countries. METHODS: Questions in the validated survey were edited if the revised Basel Statement changed intent. A total of 13 updates were made. The survey was administered via e-mail to pharmacy personnel in any hospital centre in Ghana (258 total hospitals), Nigeria (17 038 total hospitals), Malawi (499 total hospitals), Uganda (155 total hospitals), Zambia (98 total hospitals) and Zimbabwe (1389 total hospitals). Snowball sampling increased reach of the survey across each country. KEY FINDINGS: Responses were received from all six countries, with nine respondents from Ghana, 15 from Nigeria, two from Malawi, five from Uganda, nine from Zambia and four from Zimbabawe. Uganda had the highest achievement rates for tier one and tier three constructs, and Ghana had the highest achievement rate for tier two constructs. Malawi showed the lowest achievement rates in all three tiers. The six countries achieved an average of 82 per cent (SD = 24) of tier one constructs. Three tier one constructs were achieved less than 25 per cent of the time. CONCLUSION: Multiple tier one (minimum standards in hospital pharmacy practice) constructs were achieved greater than 90% of the time, possibly reflecting efforts made towards hospital pharmacy practice advancement in select countries of sub-Saharan Africa. Additionally, all countries achieved a majority of tier one overarching constructs. Despite these achievements, there are still many areas for growth, including select tier one constructs with low achievement rates.

Development and validation of a high performance liquid chromatography method to determine nevirapine in plasma in a resource-limited setting.

BACKGROUND: There are several instances where nevirapine pharmacokinetic monitoring may be useful, such as in special populations or pharmacokinetic drug interaction studies that require the ascertainment of nevirapine pharmacokinetics in the sub-Saharan region. OBJECTIVES: The main aim of this study was to produce a validated, sustainable and relevant nevirapine assay method that meets bio-analytical regulatory requirements. METHODS: The developed method utilised a Waters 2795 Alliance high performance liquid chromatography system with a 2996 photo diode array detector, an Atlantis dC18 5 micron, 3.9 mm × 150 mm analytical column and a gradient flow rate of 1 mL/min. Ultraviolet detection data were collected from 210 nm to 400 nm, extracted at 260 nm, and processed for nevirapine and internal standard peak height responses. RESULTS: The method proved to be linear (R2 0.995), precise (+1.92% - +9.69%) and accurate (-9.70% - 12.0%). Recovery for the analyte and internal standard was between 98.8% and 114%. The method showed good specificity as no interferences were caused by common African traditional medicines, anti-tuberculosis medications or other concomitant antiretrovirals nor endogenous components. CONCLUSION: The method is reproducible, relevant to our setting and uses considerably low plasma volumes with preservation of some consumables, a desirable key factor in a resource-limited setting.

Strategic establishment of an International Pharmacology Specialty Laboratory in a resource-limited setting.

BACKGROUND: A growing number of drug development studies that include pharmacokinetic evaluations are conducted in regions lacking a specialised pharmacology laboratory. This necessitated the development of an International Pharmacology Specialty Laboratory (IPSL) in Zimbabwe. OBJECTIVES: The aim of this article is to describe the development of an IPSL in Zimbabwe. METHODS: The IPSL was developed collaboratively by the University of Zimbabwe and the University at Buffalo Center for Integrated Global Biomedical Sciences. Key stages included infrastructure development, establishment of quality management systems and collaborative mentorship in clinical pharmacology study design and chromatographic assay development and validation. RESULTS: Two high performance liquid chromatography instruments were donated by an instrument manufacturer and a contract research organisation. Laboratory space was acquired through association with the Zimbabwe national drug regulatory authority. Operational policies, standard operating procedures and a document control system were established. Scientists and technicians were trained in aspects relevant to IPSL operations. A high-performance liquid chromatography method for nevirapine was developed with the guidance of the Clinical Pharmacology Quality Assurance programme and approved by the assay method review programme. The University of Zimbabwe IPSL is engaged with the United States National Institute of Allergy and Infectious Diseases Division of AIDS research networks and is poised to begin drug assays and pharmacokinetic analyses. CONCLUSIONS: An IPSL has been successfully established in a resource-limited setting through the efforts of an external partnership providing technical guidance and motivated internal faculty and staff. Strategic partnerships were beneficial in navigating challenges leading to laboratory development and training new investigators. The IPSL is now engaged in clinical pharmacology research.

Strategic establishment of an International Pharmacology Specialty Laboratory in a resource-limited setting

Background: A growing number of drug development studies that include pharmacokinetic evaluations are conducted in regions lacking a specialised pharmacology laboratory. This necessitated the development of an International Pharmacology Specialty Laboratory (IPSL) in Zimbabwe.Objectives: The aim of this article is to describe the development of an IPSL in Zimbabwe.Methods: The IPSL was developed collaboratively by the University of Zimbabwe and the University at Buffalo Center for Integrated Global Biomedical Sciences. Key stages included infrastructure development, establishment of quality management systems and collaborative mentorship in clinical pharmacology study design and chromatographic assay development and validation.Results: Two high performance liquid chromatography instruments were donated by an instrument manufacturer and a contract research organisation. Laboratory space was acquired through association with the Zimbabwe national drug regulatory authority. Operational policies, standard operating procedures and a document control system were established. Scientists and technicians were trained in aspects relevant to IPSL operations. A high performance liquid chromatography method for nevirapine was developed with the guidance of the Clinical Pharmacology Quality Assurance programme and approved by the assay method review programme. The University of Zimbabwe IPSL is engaged with the United States National Institute of Allergy and Infectious Diseases Division of AIDS research networks and is poised to begin drug assays and pharmacokinetic analyses.Conclusions: An IPSL has been successfully established in a resource-limited setting through the efforts of an external partnership providing technical guidance and motivated internal faculty and staff. Strategic partnerships were beneficial in navigating challenges leading to laboratory development and training new investigators. The IPSL is now engaged in clinical pharmacology research

Capacity for ethical and regulatory review of herbal trials in developing countries: a case study of Moringa oleifera research in HIV-infected patients.

BACKGROUND: Lack of regulatory capacity limits the conduct of ethical and rigorous trials of herbal medicines in developing countries. Sharing ethical and regulatory experiences of successful herbal trials may accelerate the field while assuring human subjects protection. The methods and timelines for the ethical and regulatory review processes for the first drug regulatory authority approved herbal trial in Zimbabwe are described in this report. METHODS: The national drug regulatory authority and ethics committee were engaged for pre-submission discussions. Six applications were submitted. Application procedures and communications with the various regulatory and ethics review boards were reviewed. Key issues raised and timelines for communications were summarized. RESULTS: There was no special framework for the approval of herbal trials. One local institutional review committee granted an exemption. Key issues raised for revision were around pre-clinical efficacy and safety data, standardization and quality assurance of the intervention as well as consenting procedures. Approval timelines ranged between eight and 72 weeks. CONCLUSIONS: In the absence of a defined framework for review of herbal trials, approval processes can be delayed. Dialogue between researchers and regulators is important for successful and efficient protocol approval for herbal trials in developing countries. TRIAL REGISTRATION: The study was registered prospectively on August 3, 2011 with clinicaltrials.gov (NCT01410058).

Effect of Moringa oleifera Lam. leaf powder on the pharmacokinetics of nevirapine in HIV-infected adults: a one sequence cross-over study.

BACKGROUND: Moringa oleifera Lam., an herb commonly consumed by HIV-infected people on antiretroviral therapy, inhibits cytochrome P450 3A4, 1A2 and 2D6 activity in vitro; and may alter the pharmacokinetics (PK) of antiretroviral drugs metabolized via the same pathways. However, in vitro drug interaction activity may not translate to a clinically significant effect. Therefore, the effect of moringa leaf powder on the PK of nevirapine in HIV-infected people was investigated. METHODS: Adult patients at steady-state dosing with nevirapine were admitted for 12-h intensive PK sampling following a 21-day herbal medicine washout. Blood sampling was repeated after 14 days of nevirapine and moringa (1.85 g leaf powder/day) co-administration. Nevirapine plasma concentrations were determined by liquid chromatography-tandem mass spectrometry. To assess the effect of moringa on nevirapine PK, the change in nevirapine area under the plasma concentration-time curve (AUC) was determined. The mean difference in pre- and post-moringa nevirapine, maximum concentration (Cmax) and concentration at 12 h (C12h) were also calculated. The PK parameters were compared by assessing the post/pre geometric mean ratios (GMRs) and associated 90% confidence intervals (CIs). RESULTS: Pharmacokinetics analyses were performed on the results from 11 participants for whom complete data were obtained. The post/pre GMRs and associated 90% CIs for nevirapine were 1.07 (1.00-1.14) for the AUC; 1.06 (0.98-1.16) for Cmax and 1.03 (0.92-1.16) for C12h. CONCLUSION: Co-administration of Moringa oleifera Lam. leaf powder at the traditional dose did not significantly alter the steady-state PK of nevirapine. Trial registration number NCT01410058 (ClinicalTrials.gov).

Quality and labeling information of Moringa oleifera products marketed for HIV-infected people in Zimbabwe.

Labeling information and quality of marketed Moringa oleifera products were assessed. Personnel in 60 pharmacies and 11 herbal shops were interviewed about the sources, dosages, indications and counseling information of Moringa oleifera products. Content analysis of written information provided on Moringa oleifera products was also done. Three samples of Moringa from popular sources were acquired to determine heavy metal content and microbial contamination. The results were compared to specified limits in the European and Chinese pharmacopeia, World Health Organization guidelines and Bureau of Indian Standards. Moringa was available as capsules or powder in 73% of the premises. Moringa was recommended for seven different disease conditions. Four different dosage regimens were prescribed. The main references cited for the counseling information were unscientific literature (62%). The selected Moringa samples were contaminated with bacteria and fungi above the European Pharmacopeia specified limits. Escherichia coli and Salmonella species were present in all three samples. All three samples contained arsenic, nickel and cadmium above the permissible limits. Moringa oleifera with variable labeling information and poor microbial and heavy metal quality is widely available in Zimbabwe.

Quality and labeling information of Moringa oleifera products marketed for HIV-infected people in Zimbabwe

Labeling information and quality of marketed Moringa oleifera products were assessed. Personnel in 60 pharmacies and 11 herbal shops were interviewed about the sources, dosages, indications and counseling information of Moringa oleifera products. Content analysis of written information provided on Moringa oleifera products was also done. Three samples of Moringa from popular sources were acquired to determine heavy metal content and microbial contamination. The results were compared to specified limits in the European and Chinese pharmacopeia, World Health Organization guidelines and Bureau of Indian Standards. Moringa was available as capsules or powder in 73% of the premises. Moringa was recommended for seven different disease conditions. Four different dosage regimens were prescribed. The main references cited for the counseling information were unscientific literature (62%). The selected Moringa samples were contaminated with bacteria and fungi above the European Pharmacopeia specified limits. Escherichia coli and Salmonella species were present in all three samples. All three samples contained arsenic, nickel and cadmium above the permissible limits. Moringa oleifera with variable labeling information and poor microbial and heavy metal quality is widely available in Zimbabwe