Guanylate cyclase stimulators for pulmonary hypertension

Area of Science:

• Cardiovascular Medicine
• Pharmacology
• Respiratory Medicine

Background:

• Pulmonary hypertension (PH) is a severe condition characterized by high blood pressure in the lung arteries, leading to right heart failure and premature death.
• Soluble guanylate cyclase (sGC) stimulators represent a novel therapeutic class with recent approvals for PH treatment.

Purpose of the Study:

• To systematically evaluate the efficacy and safety of sGC stimulators in patients across all ages and severities of pulmonary hypertension.
• To analyze treatment effects based on different subtypes of pulmonary hypertension.

Main Methods:

• A comprehensive search of CENTRAL, MEDLINE, and EMBASE databases was conducted up to February 12, 2016.
• Randomized controlled trials (RCTs) involving participants with any type of pulmonary hypertension were selected.
• Data extraction and quality assessment were performed independently by multiple reviewers, with all included studies sponsored by the drug manufacturer.

Main Results:

• Five RCTs with 962 participants were included, with short trial durations (<16 weeks).
• sGC stimulators significantly improved the six-minute walking distance (6MWD) by 45 meters in chronic thromboembolic pulmonary hypertension (CTEPH) and by 36 meters in pulmonary arterial hypertension (PAH) when phosphodiesterase-V inhibitors were excluded.
• No significant improvements in mortality or clinical worsening were observed, but a reduction in mean pulmonary artery pressure was noted. Serious adverse events did not differ significantly from placebo.

Conclusions:

• sGC stimulators effectively improve pulmonary artery pressures and 6MWD in specific PH subtypes, including PAH (treatment-naive or on prostanoid/endothelin antagonist) and inoperable/recurrent CTEPH.
• Caution is advised regarding contraindications, such as concurrent use of phosphodiesterase-V inhibitors or nitrates, due to hypotension risks.
• Evidence for sGC stimulator use in PH associated with left heart disease or in pediatric populations is currently lacking, and conclusions are based on data with limitations.