PMID- 21468170 OWN - NLM STAT- MEDLINE DCOM- 20110725 LR - 20211020 IS - 1178-2048 (Electronic) IS - 1176-6344 (Print) IS - 1176-6344 (Linking) VI - 7 DP - 2011 TI - Effect of transition from sitaxsentan to ambrisentan in pulmonary arterial hypertension. PG - 119-24 LID - 10.2147/VHRM.S15026 [doi] AB - INTRODUCTION: Currently available endothelin receptor antagonists for treating pulmonary arterial hypertension block either the endothelin (ET) receptor A or both A and B receptors. Transition from one endothelin receptor antagonist to another may theoretically alter side-effects or efficacy. We report our experience of a transition from sitaxsentan to ambrisentan, both predominant ET(A) receptor antagonists, in pulmonary arterial hypertension patients. METHODS: At Baylor Pulmonary Hypertension Center, 18 patients enrolled in the open-label extension phase of the original sitaxsentan studies (Sitaxsentan To Relieve ImpaireD Exercise) were transitioned to ambrisentan (from July 2007 to September 2007) at the time of study closure. Pre-transition (PreT), 1 month (1Mth) and 1 year (1Yr) post-transition assessments of 6-minute walk distance (6MWD), brain naturetic peptide (BNP) levels, WHO functional class (WHO FC), Borg dyspnea score (BDS), oxygen saturation, liver function, and peripheral edema were compared. RESULTS: 6MWD was 356 +/- 126 m at PreT, 361 +/- 125 m at 1Mth, and 394 +/- 114 m at 1Yr (mean +/- SD). There was no difference in the walk distance at 1Mth and 1Yr post transition compared with PreT (P=0.92, 0.41 respectively). Oxygen saturation was no different at 1Mth and 1Yr to PreT level (P=0.49 and P=0.06 respectively). BNP was 178 +/- 44 pg/mL at PreT, 129 +/- 144 pg/mL at 1Mth and 157 +/- 201 at 1Yr. Peripheral edema was present in 7/18 patients at PreT, in 8/16 patients at 1Mth, and in 6/13 patients at 1Yr post transition. Proportions of patients with edema over these 3 time points did not change significantly (P=0.803). At 1Yr, 2 patients had died, 1 had undergone lung transplantation, 1 had relocated, and 1 patient was started on intravenous prostacyclin therapy. Over 3 points (baseline, 1 month, and 1 year), there was no significant change in function class (P=0.672). CONCLUSION: Our limited data suggest that ET(A) receptor antagonists can be switched from one to another with sustained exercise capacity and maintained WHO FC with no increase in incidence of peripheral edema. CI - (c) 2011 Safdar, publisher and licensee Dove Medical Press Ltd. FAU - Safdar, Zeenat AU - Safdar Z AD - Division of Pulmonary-Critical Care Medicine, Baylor College of Medicine, Houston, Texas, USA. safdar@bcm.edu LA - eng GR - K23 HL093214/HL/NHLBI NIH HHS/United States GR - K23HL-093214/HL/NHLBI NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20110302 PL - New Zealand TA - Vasc Health Risk Manag JT - Vascular health and risk management JID - 101273479 RN - 0 (Antihypertensive Agents) RN - 0 (Endothelin A Receptor Antagonists) RN - 0 (Isoxazoles) RN - 0 (Phenylpropionates) RN - 0 (Pyridazines) RN - 0 (Thiophenes) RN - 114471-18-0 (Natriuretic Peptide, Brain) RN - HW6NV07QEC (ambrisentan) RN - J9QH779MEM (sitaxsentan) RN - S88TT14065 (Oxygen) SB - IM MH - Adult MH - Aged MH - Antihypertensive Agents/*administration & dosage/adverse effects MH - Blood Pressure/drug effects MH - *Drug Substitution MH - Dyspnea/etiology MH - Edema/etiology MH - Endothelin A Receptor Antagonists MH - Exercise Test MH - Exercise Tolerance/drug effects MH - Familial Primary Pulmonary Hypertension MH - Female MH - Humans MH - Hypertension, Pulmonary/blood/complications/drug therapy/physiopathology MH - Isoxazoles/*administration & dosage/adverse effects MH - Liver Function Tests MH - Male MH - Middle Aged MH - Natriuretic Peptide, Brain/blood MH - Oxygen/blood MH - Phenylpropionates/*administration & dosage/adverse effects MH - Pyridazines/*administration & dosage/adverse effects MH - Retrospective Studies MH - Texas MH - Thiophenes/*administration & dosage/adverse effects MH - Time Factors MH - Treatment Outcome MH - Walking PMC - PMC3064451 OTO - NOTNLM OT - 6-minute walk distance OT - echocardiogram OT - endothelial receptor antagonist OT - right heart failure EDAT- 2011/04/07 06:00 MHDA- 2011/07/26 06:00 PMCR- 2011/03/02 CRDT- 2011/04/07 06:00 PHST- 2011/03/03 00:00 [received] PHST- 2011/04/07 06:00 [entrez] PHST- 2011/04/07 06:00 [pubmed] PHST- 2011/07/26 06:00 [medline] PHST- 2011/03/02 00:00 [pmc-release] AID - vhrm-7-119 [pii] AID - 10.2147/VHRM.S15026 [doi] PST - ppublish SO - Vasc Health Risk Manag. 2011;7:119-24. doi: 10.2147/VHRM.S15026. Epub 2011 Mar 2.