A framework for the use of biological medicines in the free state province, South Africa.

PURPOSE: The use of biological medicines (BM) has increased worldwide owing to their effectiveness in the treatment of many chronic diseases. However, in South Africa, access to BM remains limited, hence, there is a need to develop strategies that will enable timely access to BM by all patients who need them. OBJECTIVE: To develop a framework for the use of BM in South Africa. METHODS: Using a Delphi questionnaire that was developed by integration of the opinions of newly qualified doctors (<2 years practice), prescribing specialists, and patients using BM, a Delphi method was used to guide an experts' panel into consensus on the different opinions in the questionnaire, and from this, a framework for the use of BM was constructed. RESULTS: From the surveys, 76.2% of the newly qualified doctors and 91.7% of the prescribing specialists indicated that they had limited knowledge on the pharmacology of BM, and, respectively, 64.5% and 77.8% admitted that their knowledge on BM was not adequate for prescribing and taking care of patients on BM. Also, 58.3% and 75% of the prescribers indicated that the high cost and the tedious procurement process, respectively, were barriers of access to BM. The Delphi panel reached consensus after two rounds, and the resultant framework recommends that, appropriate use of BM requires establishing guidelines for the use of BM, increasing BM content in the medical training programs and information resources used by healthcare professionals, enacting drug regulations and drug policies that will increase availability of BM, offering appropriate patient information and public engagement. CONCLUSION: The lack of knowledge on BM by health professionals, together with the high cost and a complex procurement processes are the major impediment to access to BM. A framework for the use of BM in South Africa was successfully developed to address these and other challenges.

Clinical Characteristics of Children with HIV Initiated on Antiretroviral Treatment at HIV Clinics in Bloemfontein, South Africa.

BACKGROUND AND OBJECTIVE: Over the past 15 years, there have been three major updates to the South African national guidelines for the management of human immunodeficiency virus (HIV) in children. The purpose of this study is to describe the clinical characteristics of children who were initiated on antiretroviral therapy (ART) in Bloemfontein, South Africa, following these national treatment guidelines. METHODS: Clinical information during initiation of ART in children aged 0-13 years was obtained from five HIV clinics in Bloemfontein from 2004 to 2019 as part of the establishment of an antiretroviral (ARV) pediatric registry at the University of the Free State. Data were analyzed for patient demographics, clinical presentation (World Health Organization (WHO) HIV-staging, growth rate and comorbid conditions), types of investigations done, and medicines prescribed. RESULTS: The number of children initiated on ART increased from 168 in the period 2004-2009 to 349 (107.8%) in 2010-2014, and then dropped to 162 in the period 2015-2019. The increase in 2010-2014 was mainly in the <2 years age group by 54.8%, and in the 5 to 10 years age group by 344.4%. In the same period, the number of children with severe illness (WHO HIV-stage 4) decreased by 20.7%, while those with mild to moderate illness (WHO HIV-stage 2 and 3) increased by 17.3%. HIV infection was more severe in children under two years as more patients in this age group presented with WHO HIV-stages 3 and 4, severe underweight (below 3rd percentile), severely suppressed CD4 count (< 25%), and a high viral load (> 1000 copies/ml). There was increased use of ABC/3TC/LPVr in the < 3-year age group and ABC/3TC/EFV in the > 3-year age group. There was reduced use of the stavudine and other regimens. CONCLUSION AND GLOBAL HEALTH IMPLICATIONS: More children were started on ART and safer ARV drugs. Children under 2 years were the most debilitated by HIV, and there was an increase in HIV prevalence among children > 5 years. New strategies for the prevention and management of HIV among children in these two age groups are needed.

The development and use of a drug-induced immunosuppressed rat-model to screen Phela for mechanism of immune stimulation.

ETHNOPHARMACOLOGY RELEVANCY: Phela, is code name for a medicinal product made from four South African traditional medicinal plants (Clerodendrum glabrum E. Mey, Polianthes tuberosa (Linn.), Rotheca myricoides (Hochst.) Steane & Mabb. and Senna occidentalis (L.) Link). All these plants have established traditional use in a wide spectrum of diseases. Phela is under development for use as an immune booster in immunocompromised patients, which includes patients with the human immunodeficiency virus (HIV). Already several studies, both pre-clinical and clinical, have shown that Phela is a safe and effective immune booster. Despite some studies on the action of Phela, the mechanism of action by Phela is still not known. Understanding the mechanism of action will enable safer and effective use of the drug for the right indications. Unfortunately, there is no well characterized test-system for screening products for immune stimulant activity. Therefore, the objective of this study was to use Phela as the test article, to develop and validate a rat-model (test system) by which to screen medicines for immune stimulant activity. MATERIAL AND METHODS: First, the batch of Phela used was authenticated by high performance liquid chromatography (HPLC) techniques; analytical methods for the immunosuppressant drugs, cyclosporine A (CsA), cyclophosphamide (CP) and dexamethasone (Dex) were developed and validated; and a slide-A-Lyzer dialysis was used to test for potential interactions in rat plasma of Phela with CsA, CP and Dex. Thereafter, using Sprague Dawley (SD) rats and in separate experiments, the effective dose of Phela in the study animals was determined in a dose ranging study with levamisole, a known immune stimulant as the positive control; the appropriate doses for immunosuppression by CsA, CP and Dex were determined; the time to reach 'established immunosuppression' with each drug was determined (it was also the time for intervention with Phela); and eventually, the effect of Phela on the immune system was tested separately for each drug induced immunosuppression. The immune system was monitored by observing for changes in plasma profiles of IL-2, IL-10, IgG, IgM, CD4 and CD8 cell counts at appropriate intervals, while in addition to function tests, the kidneys, liver, spleen, thymus, were weighed and examined for any pathology. RESULTS: The chromatographic fingerprint certified this batch of Phela as similar to the authentic Phela. There was no significant interaction between Phela and CsA, CP and Dex. The effective dose of Phela was determined to be 15.4mg/kg/day. Phela led to a moderate increase in the immune parameters in the normal rats. Co-administration of Phela 15mg/kg/day orally for 21 days with CsA led to stoppage and reversal of the immunosppressive effects of CsA that were exhibited as increased IL-2, IL-10, CD4 and CD8 counts, implying that Phela stimulates the cell mediate immunity (CMI). For CP, Phela led to stoppage and reversal, though moderate, of CP-induced suppression of IL-10, IgM and IgG only, implying that Phela stimulates the humoral immunity (HI) too. Phela had no effect on Dex induced immunosuppression. Stimulation of the CMI means that Phela clinical testing programme should focus on diseases or disorders that compromise the CMI, e.g., HIV and TB. The stimulation of the HI immunity means that Phela may stimulate existing memory cells to produce antibodies. CONCLUSION: The present study has revealed Phela's mechanism of action as mainly by stimulation of the CMI, implying that the use of Phela as immune booster in HIV patients is appropriate; and that using Phela as the test product, a rat model for screening medicinal products for immune stimulation has been successfully developed and validated, with a hope that it will lead to the testing of other related medicinal products.

Changes in IL-2 and IL-10 during Chronic Administration of Isoniazid, Nevirapine, and Paracetamol in Rats.

The aim of this study was to illustrate the initial subclinical drug-induced liver injury and the associated adaptive immune response by monitoring for the changes in plasma IL-2, IL-10, and some cytochrome P450 activity during chronic administration of nevirapine (NVP), isoniazid (INH), and paracetamol (PAR) in rats without clinical hepatotoxicity. Male Sprague-Dawley (SD) rats were divided into four groups (saline (S), NVP, INH, and PAR) of 25 animals each. The drugs were administered daily for 42 days at therapeutic doses (NVP 200 mg/kg, PAR 500 mg/kg, and INH 20 mg/kg) to the respective groups by oral gavage and five rats per group were sacrificed weekly. All the three drugs induced a subclinical liver injury in the first 2-3 weeks followed by healing, indicating adaption. The liver injury was pathologically similar and was associated with immune stimulation and increased cytochrome P450 activity. NVP- and PAR-induced liver injury lasted up to 14 days while that for INH lasted for 28 days. NVP-induced liver injury was associated with increased IL-2, CD4 count, and CYP3A2 activity, followed by increased IL-10 during the healing phase. In conclusion, the initial drug-induced subclinical liver injury, its spontaneous healing, and the associated adaptive immune response have been demonstrated.

Co-administration of fresh grape fruit juice (GFJ) and bergamottin prevented paracetamol induced hepatotoxicity after paracetamol overdose in rats.

The aim of this study was to evaluate small doses of known cytochrome P450 enzyme inhibitors, grapefruit juice (GFJ) and one of its components, bergamottin (BGT), for the prevention of paracetamol (PAR)-induced hepatotoxicity after overdose in rats. Six groups of 15 Sprague Dawley (SD) rats each were treated with single oral doses of either saline, PAR only 1725 mg/kg, PAR + GFJ low dose (2 ml) and PAR + GFJ high dose (3 ml), PAR + BGT 0.05 mg/kg (BGT-low) and PAR + BGT 0.22 mg/kg (BGT-high). Thereafter, 5 rats from each group were sacrificed after 24, 48 and 72 h and, on each occasion, blood samples were collected for determination of liver and renal function, full blood count (FBC) and PAR concentration. A piece of liver was sent for histopathology. By 48 h the liver enzymes in the PAR-only group were significantly (P < 0.05) higher than in the PAR + GFJ and PAR + BGT groups, i.e., alanine transaminase (ALT) 837 ± 268 u/L and aspertate transaminase (AST) 1359 ± 405 for PAR only; versus ALT 34 ± 48.8 u/L and AST 238 ± 221 for PAR + GFJ-high; ALT 22 ± 13.9 and AST168 ± 49.6 for PAR + BGT-high; and ALT 52 ± 7.2 u/L and AST 147 ± 153 for the control group. The results correlated with the histopathology findings where livers of the PAR-only group exhibited severe centrilobular and hepatocyte necrosis. In conclusion, GFJ and BGT prevented PAR-induced hepatotoxicity after PAR overdose in rats, and this calls for appropriate observation studies in humans.

The current status and trend of clinical pharmacology in developing countries.

BACKGROUND: Several international forums for promoting clinical pharmacology in developing countries have been held since 1980, and several clinical pharmacology programmes targeting developing countries were instituted such that the status of clinical pharmacology in developing countries is not where it was 50 years ago. Therefore, a survey and an appraisal of the literature on the current status of clinical pharmacology in developing countries were undertaken with a hope that it would enable development of appropriate strategies for further promotion of clinical pharmacology in these countries. METHODS: First, nine determinants (or enabling factors) for running a successful clinical pharmacology programme were identified, i.e., disease burden, drug situation, economic growth, clinical pharmacology activities, recognition, human capital, government support, international collaboration, and support for traditional/alternative medicines. These factors were then evaluated with regard to their current status in the developing countries that responded to an electronic questionnaire, and their historical perspective, using the literature appraisal. From these, a projected trend was constructed with recommendations on the way forward. RESULTS: Clinical pharmacology services, research and teaching in developing countries have improved over the past 50 years with over 90% of countries having the appropriate policies for regulation and rational use of medicines in place. Unfortunately, policy implementation remains a challenge, owing to a worsening disease burden and drug situation, versus fewer clinical pharmacologists and other competing priorities for the national budgets. This has led to a preference for training 'a physician clinical pharmacologist' in programmes emphasizing local relevancy and for a shorter time, and the training of other professionals in therapeutics for endemic diseases (task shifting), as the most promising strategies of ensuring rational use of medicines. CONCLUSION: Clinical pharmacology in developing countries is advancing in a different way to that in the developed world and continuing support for these efforts will go a long way in promoting improved health for all.

The role of the immune system in nevirapine-induced subclinical liver injury of a rat model.

In this study, the role of the immune system in nevirapine- (NVP-) induced subclinical liver injury was investigated by observing for changes of some immune parameters during the initial stages of NVP-induced hepatotoxicity in a rat model. In the acute phase, two test-groups of 10 Sprague-Dawley rats each were administered with bacterial lipopolysaccharide (LPS) or saline (S) intraperitoneally, followed by oral NVP, after which 5 rats from each group were sacrificed at 6 and 24 hours. For the chronic phase, two groups of 15 rats each received daily NVP, and on days 7, 14, and 21, five rats from each group were administered with either LPS or S, followed by that day's NVP dose, and were sacrificed 24 hours later. NVP caused liver injury up to seven days and progressively increased IL-2 and IFN-γ levels and lymphocyte count over the 21 days. NVP-induced liver injury was characterized by apoptosis and degeneration changes, while, for LPS, it was cell swelling, leukostasis, and portal inflammation. Coadministration of NVP and LPS attenuated NVP-induced liver injury. In conclusion, the immune system is involved in NVP toxicity, and the LPS effects may lay the clue to development of therapeutic strategies against NVP-induced hepatotoxicity.

Evaluation of traditional medicines I: identification of PHELA using different chromatographic techniques.

PHELA is a herbal mixture of four African traditional medicinal plants that has been used for decades in wasting conditions and is now being developed by the Medical Research Council (MRC) as an immune booster for patients with compromised immune system. A chromatographic fingerprint of PHELA was needed for quality control purposes. Here, a comprehensive method for fingerprinting of PHELA using different chromatographic techniques is described. It involved extraction of the PHELA by either acidic or a simple 'salting-out' method, followed by Thin Layer Chromatography (TLC) analysis and/or preparative Column Chromatography (CC). The products were thereafter analyzed by High Performance Liquid Chromatography with UV-detector (HPLC-UV), HPLC with fluorescence-detector (HPLC-FL) and Gas-Chromatography with a Mass Selective Detector spectrometer (GC-MSD). The fingerprints were successfully used to differentiate PHELA from another common herbal product made from Hypericum perforatum (St. John's Wort), thereby illustrating its high potential for use in fingerprinting of PHELA and in differentiating it from other herbal medicines. By validating the different chromatographic techniques on the standardized extraction methods, this approach will enable wide application in quality control of PHELA using acceptable procedures, thereby promoting effective monitoring of the finished product in all countries where it will be used.

Evaluation of traditional medicines III: the mechanism of immune modulation by PHELA.

PHELA is a herbal traditional medicine that is under development for use as an immune booster in immune compromised individuals. Therefore, the aim of this study was to determine PHELA's mechanism of action by observing for changes in cytokine profiles. Four groups of Sprague Dawley rats (n = 8) were treated daily and separately with normal-saline, cyclosporine-A, PHELA-only and PHELA+ cyclosporine-A. Thereafter, 4 animals from each group were sacrificed after 7 and 14 days of treatment. Serum Th1 cytokines (IL-2, IFN-γ and TNF-α) and Th2 cytokines (IL-4 and IL-10) were measured by ELISA. The concentrations of Th1 cytokines in the PHELA-only treated group were similar to the control group on days 7 and 14. However, the Th1 cytokines were higher in the PHELA+cyclosporine-A treated group compared to cyclosporine-A group, and cyclosporine-A concentrations were similar in both groups. These results show that PHELA did not stimulate Th1 cytokines of a normal immune system but stimulated them when the immune system was suppressed by cyclosporine-A. In conclusion, PHELA is an immune-stimulant to a compromised immune system.

Evaluation of traditional medicines II: the use of metabolite peak-kinetics to monitor PHELA in rat plasma.

PHELA is a herbal mixture of four African traditional medicinal plants that is under development by the Medical Research Council (MRC) for use as an immune stimulant in immune compromised individuals. Before major in vivo investigations could be conducted, there was a need to establish a plasma marker for concentration monitoring of PHELA. Chromatographic separation was achieved using a C18 RP column (250 mm × 4.6 mm × 5 µm), 70% acetonitrile in water and fluorescent detection. Three groups of rats (n=5) were administered with PHELA (15.4 mg/kg) and one rat from each group was sacrificed at 1, 2, 4, 6 and 8 hours. Surprisingly, on the HPLC analysis, none of the marker peaks of spiked plasma were detectable in the plasma of treated animals. Instead, a new peak was observed at 9.2 minutes, which implied that it was a metabolite of PHELA. Using peak area per unit plasma volume (PK-area/L), the relevant pharmacokinetic parameters were derived. The metabolite's half-life was 3.47±0.35 hours and reached maximum concentration at 4.67 ± 1.15 hrs. It was estimated that with once daily dosing of PHELA, the concentration at steady state (Css) would be 47.52 ± 5.94 PK-area/L with no drug accumulation (Acc index =.009 ± 0.004). In conclusion, the use of peak area per unit volume to derive pharmacokinetics of unknown compounds (Peak-kinetics) and to confirm ingestion of PHELA were demonstrated with a hope that they may appeal to those experiencing similar problems with monitoring of herbal products of which little is known.

Interaction between valproic acid and acyclovir after intravenous and oral administration in a rabbit model.

This study was undertaken to investigate the effect of co-administration of valproic acid and acyclovir on the pharmacokinetic parameters of each other. Fifteen white New Zealand rabbits were divided into three groups: A, B and C. Group A received acyclovir only, group B received valproic acid only and group C received a combination of acyclovir and valproic acid. In a cross-over design, the intravenous route was studied first, followed by the oral route after a 2-week wash-out period. Blood samples were drawn over 10 hr and the pharmacokinetic parameters were derived from the concentrations. After intravenous administration, the area under the plasma concentration time curve and plasma concentrations of acyclovir in group C were higher than in group A, while the volume of distribution and plasma clearance of acyclovir in group C were only 12.8% and 10.36% of those of group A, respectively. A similar trend was observed after oral administration. However, the bioavailability (F) of acyclovir was 8.4% in group A versus 1.5% in group C. In addition, the concentrations and kinetic parameters of valproic acid between the two groups after oral and intravenous administration were not different. In conclusion, co-administration of single doses of acyclovir and valproic acid led to reduced oral bioavailability of acyclovir, but increased concentrations of acyclovir due to reduced volume of distribution and clearance. These observations call for a cautious approach to the concomitant use of the two drugs until human studies are done.

The role of cytochrome P450 in antiretroviral drug interactions.

As millions of patients with HIV/AIDS are put on treatment with the highly active antiretroviral therapy (HAART), drug interactions have become a major concern for healthcare providers. The use of HAART as a combination of 3 - 4 drugs creates potential for antiretroviral (ARV) drug interactions, and this is complicated by the addition of other drugs for treatment of other ailments such as comorbid chronic conditions and/or opportunistic infections. It has been observed that most ARV drug interactions involve drugs that interact with CYP enzymes. Specifically, protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) are the most implicated in ARV drug interactions and are metabolised by CYP isoenzymes. Because PIs and NNRTIs can also inhibit and induce some of the CYP isoenzymes, they often interfere with the metabolism of several drugs eliminated by CYP isoenzymes, and the converse is true. The drug groups most implicated in CYP-mediated interactions with ARV drugs include: rifamycins; statins; antibiotics; antifungals; antiulcer drugs; contraceptives; immunosuppressant drugs; drugs for erectile dysfunction; drugs of abuse; drugs for treatment of addiction; benzodiazepines; anticonvulsants; psychotropic agents; herbal products; antiarrhythmias; antimalarials; anticoagulants; and antiasthma drugs. Unfortunately, this information is published in different resources where it may not be accessible to many, and is also liable to misinterpretation if read in isolation. Here, this information has been pooled and discussed with a hope that it will enable appropriate use in patients with HIV/AIDS. The review was confined to CYP-associated ARV drug interactions to emphasise that prevention of ARV drug interactions requires thorough knowledge of CYP function and regulation by healthcare providers.

The effect of isoniazid containing regimen on CYP2E1 during antituberculosis therapy.

Because isoniazid is a selective inducer of CYP2E1 and isoniazid-induced hepatotoxicity is believed to be due to activation of its metabolites by CYP450, this study was undertaken to determine the effect of isoniazid containing regimen on CYP2E1 in TB-patients. The activity of CYP2E1 in 11 newly diagnosed TB-patients (5 F, 6 M) was investigated before (day 0) and during (day 14) treatment for tuberculosis. CYP2E1 activity was measured using the plasma metabolic ratio (MR) of 6-hydroxy-chlorzoxazone to chlorzoxazone, while CYP2E1 quantity in the peripheral lymphocytes was measured using SDS-PAGE. By day 14 of anti-tuberculosis treatment, the activity of CYP2E1 was inhibited by 72% in 8 patients, but increased in 3 patients. The MR for the 8 patients was reduced from (Median & Range) 2.78 (1.1-21.5) on day 0, to 0.75 (0.4-1.22) on day 14, (P = 0.0006). Renal function was normal before and during the investigation. The detection of CYP2E1 by in peripheral lymphocytes was so variable that it could not be correlated with enzyme activity. Nevertheless, its detection in peripheral lymphocytes where normally is not resident indicates that CYP2E1 was induced by isoniazid. These results indicate that during treatment for tuberculosis with isoniazid containing regimen, CYP2E1 is induced but its activity is inhibited by isoniazid.

A model for selecting assessment methods for evaluating medical students in African medical schools.

Introduction of more effective and standardized assessment methods for testing students' performance in Africa's medical institutions has been hampered by severe financial and personnel shortages. Nevertheless, some African institutions have recognized the problem and are now revising their medical curricula, and, therefore, their assessment methods. These institutions, and those yet to come, need guidance on selecting assessment methods so as to adopt models that can be sustained locally. The authors provide a model for selecting assessment methods for testing medical students' performance in African medical institutions. The model systematically evaluates factors that influence implementation of an assessment method. Six commonly used methods (the essay examinations, short-answer questions, multiple-choice questions, patient-based clinical examination, problem-based oral examination [POE], and objective structured clinical examination) are evaluated by scoring and weighting against performance, cost, suitability, and safety factors. In the model, the highest score identifies the most appropriate method. Selection of an assessment method is illustrated using two institutional models, one depicting an ideal situation in which the objective structured clinical examination was preferred, and a second depicting the typical African scenario in which the essay and short-answer-question examinations were best. The POE method received the highest score and could be recommended as the most appropriate for Africa's medical institutions, but POE assessments require changing the medical curricula to a problem-based learning approach. The authors' model is easy to understand and promotes change in the medical curriculum and method of student assessment.