Long-Term Extension Study of Inhaled Nitric Oxide (iNO) for PAH

Inclusion Criteria: * Signed Informed Consent Form prior to the initiation of any study mandated procedures or assessments. * PAH subjects who have completed all EOS assessments in IK-7001-PAH-201 and PULSE-PAH-004 and have continued drug/device usage. * Subjects are willing and considered in the judgement of the Investigator able to use the INOpulse device continuously for up to 24 hours per day. * All female subjects must be willing to continue to take adequate precaution to avoid pregnancy. * Subjects in need for continued treatment with iNO in the opinion of the treating physician and agreement from Sponsor. Exclusion Criteria: * Subjects who require treatment with riociguat * Subjects who early discontinued drug/device usage due to withdrawal of consent or an AE requiring termination from treatment in IK-7001-PAH-201