Acknowledgement to Referees

RTI Health Solutions, Research Triangle Park, NC, USA Dr Ulrich Granzer, PhD. Granzer Regulatory Consulting & Services, Munich, Germany Professor Jan D. Hirsch, BSPharm PhD. University of California, Irvine, CA, USA Mr Alan Hunter, LLB BPharm, FPS, FTOPRA. Dutch Medicines Evaluation Board, Utrecht, The Netherlands Dr Shunsuke Ono, PhD. University of Tokyo, Tokyo, Japan Dr María Proupín-Pérez, PhD. CSL Behring Innovation GmbH, Marburg, Germany Professor Sir Michael Rawlins, BSc MD FRCP FFPM. Horizon Pharma, Deerfield, IL, USA Dr Honorio Silva, MD. [Extracted from the article]

Controversial COVID-19 Cures: Hydroxychloroquine and Oleander Pediatric Ingestion Simulation Cases.

INTRODUCTION: The use of hydroxychloroquine has dramatically increased since being touted as a potential therapeutic in combating coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus. This newfound popularity increases the risk of accidental pediatric ingestion, whereby just one or two tablets causes morbidity and mortality from seizures, cardiac dysrhythmias, and cardiogenic shock. The unique management of hydroxychloroquine overdose makes it imperative for emergency medicine physicians to have familiarity with treating this condition. Similarly, ​​during the COVID-19 pandemic, there have been publicized cases touting extracts of oleander as being a potential therapeutic against the illness. Since it is commonly available and potentially lethal ingestion with a possible antidote, we developed a simulation case based on the available literature. The two cases were combined to create a pediatric toxicology curriculum for emergency medicine residents and medical students. Both of these treatments were selected as simulation cases since they were being touted by prominent national figures as potential cures for COVID-19. METHODS: Two series of simulation cases were conducted in a high-fidelity simulation lab with emergency medicine residents and medical students. The hydroxychloroquine simulation case involved the management of a four-year-old male who presented to the emergency department with nausea, vomiting, and tachycardia after ingesting hydroxychloroquine tablets. As the case unfolded, the child became increasingly unstable, eventually experiencing QT prolongation, torsades de pointes, and ventricular fibrillation arrest requiring appropriate resuscitation to achieve a return of spontaneous circulation. The oleander simulation case involved the management of a three-year-old male who presented to the emergency department with nausea, vomiting, and tachycardia after ingesting parts of an unknown plant. As that case progresses, the child becomes increasingly unstable, eventually experiencing atrial fibrillation, bradycardia, and degenerating into pulseless electrical activity and cardiac arrest requiring appropriate resuscitation to achieve the return of spontaneous circulation. Both series of simulation cases were modifiable based on trainee level and had the ability to include ancillary emergency department staff. RESULTS: Each simulation case was performed six times at our simulation center, with a total of 22 learners for the hydroxychloroquine case, and 14 for the oleander case. Through pre- and post-simulation confidence assessments, learners demonstrated increases in knowledge of toxidromes, evaluating pediatric overdoses, treating cardiac dysrhythmias, performing pediatric advanced life support, and managing post-arrest care. Learners also demonstrated improvements in recognizing the unique treatment of hydroxychloroquine and oleander toxicity, the toxic dose of both substances in a child, and the most common electrolyte anomaly seen in each toxicity. DISCUSSION: Simulation training enables learners to manage rare and complex disease processes. These cases were designed to educate trainees in recognizing and treating rare overdoses of emerging "therapeutics" that were touted early in the COVID-19 pandemic.

Efficacy of oleandrin and PBI-05204 against bovine viruses of importance to commercial cattle health.

BACKGROUND: Bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV). and bovine coronavirus (BCV) threaten the productivity of cattle worldwide. Development of therapeutics that can control the spread of these viruses is an unmet need. The present research was designed to explore the in vitro antiviral activity of the Nerium oleander derived cardiac glycoside oleandrin and a defined N. oleander plant extract (PBI-05204) containing oleandrin. METHODS: Madin Darby Bovine Kidney (MDBK) cells, Bovine Turbinate (BT) cells, and Human Rectal Tumor-18 (HRT-18) cells were used as in vitro culture systems for BVDV, BRSV and BCV, respectively. Cytotoxicity was established using serial dilutions of oleandrin or PBI-05204. Noncytotoxic concentrations of each drug were used either prior to or at 12 h and 24 h following virus exposure to corresponding viruses. Infectious virus titers were determined following each treatment. RESULTS: Both oleandrin as well as PBI-05204 demonstrated strong antiviral activity against BVDV, BRSV, and BCV, in a dose-dependent manner, when added prior to or following infection of host cells. Determination of viral loads by PCR demonstrated a concentration dependent decline in virus replication. Importantly, the relative ability of virus produced from treated cultures to infect new host cells was reduced by as much as 10,000-fold at noncytotoxic concentrations of oleandrin or PBI-05204. CONCLUSIONS: The research demonstrates the potency of oleandrin and PBI-05204 to inhibit infectivity of three important enveloped bovine viruses in vitro. These data showing non-toxic concentrations of oleandrin inhibiting infectivity of three bovine viruses support further investigation of in vivo antiviral efficacy.

Antiviral activity of oleandrin and a defined extract of Nerium oleander against SARS-CoV-2.

With continued expansion of the coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome 2 (SARS-CoV-2), both antiviral drugs as well as effective vaccines are desperately needed to treat patients at high risk of life-threatening disease. Here, we present in vitro evidence for significant inhibition of SARS-CoV-2 by oleandrin and a defined extract of N. oleander (designated as PBI-06150). Using Vero cells, we found that prophylactic (pre-infection) oleandrin (as either the pure compound or as the active principal ingredient in PBI-06150) administration at concentrations as low as 0.05 µg/ml exhibited potent antiviral activity against SARS-CoV-2, with an 800-fold reduction in virus production, and a 0.1 µg/ml concentration resulted in a greater than 3000-fold reduction in infectious virus production. The half maximal effective concentration (EC50) values were 11.98 ng/ml when virus output was measured at 24 h post-infection, and 7.07 ng/ml measured at 48 h post-infection. Therapeutic (post-infection) treatment up to 24 h after SARS-CoV-2 infection of Vero cells also reduced viral titers, with 0.1 µg/ml and 0.05 µg/ml concentrations causing greater than 100-fold reduction as measured at 48 h, and the 0.05 µg/ml concentration resulting in a 78-fold reduction. Concentrations of oleandrin up to 10 µg/ml were well tolerated in Vero cells. We also present in vivo evidence of the safety and efficacy of defined N. oleander extract (PBI-06150), which was administered to golden Syrian hamsters in a preparation containing as high as 130 µg/ml of oleandrin. In comparison to administration of control vehicle, PBI-06150 provided a statistically significant reduction of the viral titer in the nasal turbinates (nasal conchae). The potent prophylactic and therapeutic antiviral activities demonstrated here, together with initial evidence of its safety and efficacy in a relevant hamster model of COVID-19, support the further development of oleandrin and/or defined extracts containing this molecule for the treatment of SARS-CoV-2 and associated COVID-19 disease and potentially also for reduction of virus spread by persons diagnosed early after infection.

Antiviral Effects of Oleandrin.

Over the past 15 years, investigators have reported on the utility and safety of cardiac glycosides for numerous health benefits including those as treatments for malignant disease, stroke-mediated ischemic injury and certain neurodegenerative diseases. In addition to those, there is a growing body of evidence for novel antiviral effects of selected cardiac glycoside molecules. One unique cardiac glycoside, oleandrin derived from Nerium oleander, has been reported to have antiviral activity specifically against 'enveloped' viruses including HIV and HTLV-1. Importantly, a recent publication has presented in vitro evidence for oleandrin's ability to inhibit production of infectious virus particles when used for treatment prior to, as well as after infection by SARS-CoV-2/COVID-19. This review will highlight the known in vitro antiviral effects of oleandrin as well as present previously unpublished effects of this novel cardiac glycoside against Ebola virus, Cytomegalovirus, and Herpes simplex viruses.