OBJECTIVES:  Past experience using third party vendors to administer clinical programs for patients with chronic, progressive conditions resulted in low opt-in rates.  A direct approach using the Specialty Pharmacy (SP) may have a better opt-in rate and compliance and persistence (C&P) with medication regimens.  The objective of this interventional program administered by a specialty pharmacy (SP) [Accredo Specialty Pharmacy, Memphis, TN] was to evaluate a C&P program for bosentan (Actelion Pharmaceuticals Ltd., Allschwil, Switzerland) by comparing Pulmonary Arterial Hypertension (PAH) patients in the C&P program to a historical control group. METHODS: A pharmacist-based C&P program was administered directly by the SP that provided the medication and counseling, and patients were initially ranked using Morisky medication adherence scale to assess risk of non-adherence. Retrospective analysis was performed to measure program opt-in rate and C&P.   Claims from a historical group (controls) and from the intervention group (cases) that received the SP-based C&P program between 04/29/2013 through 11/30/2013 were analyzed. Claims for naïve users of  bosentan were reviewed at 120 days and 180 days for both persistence (bosentan claims not spaced > 45 days apart) and compliance (number of calendar days supplied with bosentan divided by 120 or 180 days).  Early refills were adjusted when considering days covered. Opt-in rates were also measured. RESULTS: Opt-in rate for the enhanced SP-based C&P program was robust at 97%. No statistically significant difference was seen between the control and case groups for persistence or compliance. Use of the Morisky scale to drive the number of pharmacist interventions did not impact outcomes in the case group. CONCLUSIONS: SP-based programs can achieve high participation that may drive medication compliance, which is essential in progressive diseases like PAH. Future programs should be SP-based to replicate the high opt-in rate while establishing new interventions to drive compliance and persistence.