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Strand TE, Khiabani HZ, Boico A, Radiloff D, Zhao Y, Hamilton KL, Christians U, Klawitter J, Noveck RJ, Piantadosi CA, Bell C, Irwin D, Schroeder T. The novel combination of theophylline and bambuterol as a potential treatment of hypoxemia in humans. Can J Physiol Pharmacol 2017; 95:1009-1018. [PMID: 28467859 DOI: 10.1139/cjpp-2016-0635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hypoxemia can be life-threatening, both acutely and chronically. Because hypoxemia causes vascular dysregulation that further restricts oxygen availability to tissue, it can be pharmacologically addressed. We hypothesized that theophylline can be safely combined with the β2-adrenergic vasodilator bambuterol to improve oxygen availability in hypoxemic patients. Ergogenicity and hemodynamic effects of bambuterol and theophylline were measured in rats under hypobaric and normobaric hypoxia (12% O2). Feasibility in humans was assessed using randomized, double-blind testing of the influence of combined slow-release theophylline (300 mg) and bambuterol (20 mg) on adverse events (AEs), plasma K+, pulse, blood pressure, and drug interaction. Both drugs and their combination significantly improved hypoxic endurance in rats. In humans, common AEs were low K+ (<3.5 mmol/L; bambuterol: 12, theophylline: 4, combination: 13 episodes) and tremors (10, 0, 14 episodes). No exacerbation or serious AE occurred when drugs were combined. A drop in plasma K+ coincided with peak bambuterol plasma concentrations. Bambuterol increased heart rate by approximately 13 bpm. Drug interaction was present but small. We report promise, feasibility, and relative safety of combined theophylline and bambuterol as a treatment of hypoxemia in humans. Cardiac safety and blood K+ will be important safety endpoints when testing these drugs in hypoxemic subjects.
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Affiliation(s)
- Trond-Eirik Strand
- a Norwegian Armed Forces Medical Services, Institute of Aviation Medicine, 0313 Oslo, Norway
| | - Hasse Z Khiabani
- b Department of Pharmacology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
| | - Alina Boico
- c Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Yulin Zhao
- c Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | - Karyn L Hamilton
- e Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
| | - Uwe Christians
- f iC42 Integrated Solutions in Clinical Research and Development, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jelena Klawitter
- f iC42 Integrated Solutions in Clinical Research and Development, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Robert J Noveck
- g Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Christopher Bell
- e Department of Health and Exercise Science, Colorado State University, Fort Collins, CO 80523, USA
| | - David Irwin
- i Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Thies Schroeder
- i Department of Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO 80045, USA.,j Department of Biochemistry and Pharmacology, University of Mainz, 55128 Mainz, Germany
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Sildenafil for the treatment of pulmonary hypertension in pediatric patients. Pediatr Cardiol 2009; 30:871-82. [PMID: 19705181 DOI: 10.1007/s00246-009-9523-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 08/04/2009] [Indexed: 10/20/2022]
Abstract
Sildenafil is a phosphodiesterase 5 inhibitor widely used for the treatment of pulmonary hypertension in children. Despite limited available safety and efficacy evidence, use of sildenafil continues to increase. To date, sildenafil use for pediatric pulmonary hypertension has been characterized for 193 children through 16 studies and 28 case series and reports. The primary efficacy data suggest that sildenafil is beneficial for facilitating the weaning of inhaled nitric oxide in children after cardiac surgery. Compiled safety data suggest that sildenafil is well tolerated among children with idiopathic pulmonary arterial hypertension and pulmonary arterial hypertension associated with congenital heart disease. This review summarizes the available data describing the use, safety, and efficacy of sildenafil for children with pulmonary hypertension.
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