An Open Label Extension Study to Evaluate the Safety of Continued Therapy of Subcutanous Remodulin® in Pulmonary Arterial Hypertension

Inclusion Criteria: A subject is eligible for inclusion in this study if all of the following criteria apply:

1. The subject voluntarily gives written informed consent to participate in the study.

2. The subject participated in and completed study CVT-CV-003.

3. Sexually active women of childbearing potential must practice true abstinence fromintercourse when it is in line with their preferred and usual lifestyle, or use twodifferent forms of highly effective contraception. Medically acceptable forms ofeffective contraception include: (1) approved hormonal contraceptive (such as birthcontrol pills), (2) barrier methods (such as a condom or diaphragm) used with aspermicide, (3) an intrauterine device (IUD), or (4) partner vasectomy. Women of childbearing potential include any females who have experienced menarche and who have notundergone successful surgical sterilization (hysterectomy, bilateral tubal ligation orbilateral oophorectomy) or are not postmenopausal (defined as amenorrhea for at least 12 consecutive months). Males participating in the study must use a condom during the length of the study, andfor at least 48 hours after discontinuing study medication.

4. The subject has not developed a concurrent illness or condition during the conduct ofthe previous study (including but not restricted to, sleep apnea, chronic renalinsufficiency, anemia, uncontrolled systemic hypertension or left sided heart disease)that would make participation in this study detrimental to the subject's health in theopinion of the Investigator.

5. In the opinion of the Principal Investigator, the subject is able to communicateeffectively with study personnel, is considered reliable, willing and likely to becooperative with protocol requirements, including attending all study visits, and ismentally and physically capable of administering Remodulin by continuous SC infusionusing a micro infusion pump.

Exclusion Criteria: A subject is not eligible for inclusion in this study if any of the following criteriaapply:

1. The subject permanently discontinued Remodulin during study CVT-CV-003.

2. The subject is pregnant or lactating.