Introduction Orthostatic hypotension (OH) is associated with cardiovascular mortality and morbidity. Non-pharmacological and pharmacological therapies are employed in the management of OH. The aim of this systematic review and meta-analysis is to provide an up-to-date review of the efficacy parameters of pharmacological therapies. Methods Medline, Embase, Cochrane Library, and Scopus were searched (inception-July 2021), and published articles with randomized control trials, meeting inclusion and exclusion criteria were quality assessed (Risk of Bias 2 tool). Assessment for trends in patient-related outcome measures and postural blood pressure improvement was undertaken. Studies reporting postural systolic blood pressure (SBP) before and after intervention in comparison to placebo were included in a meta-analysis using inverse -variance in a random-effects model. Results 19 articles were included in the systematic review. The orthostatic symptoms questionnaire (OHQ) was the most common patient-related outcome measure utilized in trials. Six studies included in the meta-analysis demonstrated that pharmacological therapies (pyridostigmine, midodrine, atomoxetine, yohimbine) improved postural SBP compared to placebo, with a mean rise of 12.50 mmHg [95% CI: 6.01, 18.98; p value<0.001, I2 =97%]. Midodrine showed the highest impact on SBP, with a mean SBP of 16.11 mmHg [95% CI: 5.59, 26.63; p=0.003, I2 =99%]. Conclusions Pharmacological treatment can significantly increase postural SBP, however with significant heterogeneity related to trial designs. Further efforts to homogenize outcome measures, incorporating symptom improvement and reduction in the postural drop and testing for a prolonged duration of therapy would strengthen the evidence, and improve the translatability of findings in clinical settings.

Vaccines have reduced the transmission and severity of COVID-19 but there remains a paucity of efficacious treatment for drug resistant strains and more susceptible individuals. Repurposing existing drugs is a timely, safe and scientifically robust method for treating pandemics such as COVID-19. Here, we review the pharmacology and scientific rationale for repurposing niclosamide, an anti-helminth already in human use as a treatment for COVID-19. In addition to potent antiviral activity, niclosamide has shown pleiotropic anti-inflammatory, antibacterial, bronchodilatory and anticancer effects in numerous pre-clinical and early clinical studies. The advantages and rationale for nebulised and intranasal formulations of niclosamide, which target the site of primary infection in COVID-19, are reviewed. Finally, we discuss the TACTIC-E clinical trial, an international COVID-19 therapeutic platform trial for the use of licensed and novel therapeutic agents, which is investigating niclosamide as a promising candidate against SARS-CoV-2.