At the end of March, the Food and Drug Administration (FDA) approved four generic versions of ambrisentan, the pulmonary arterial hypertension-targeted therapy marketed as the brand name Letairis®. All the new generic ambrisentan products (and Letairis) will be available through specialty pharmacies. At least one will also be available at retail locations.

REMS Enrollment
Individuals currently enrolled in the Letairis Risk Evaluation and Mitigation Strategies (REMS) program should note that there are now two REMS programs, each covering different ambrisentan products for the purpose of managing drug-associated risks.

Current Letairis REMS participants will be automatically enrolled in the renamed Ambrisentan REMS program covering four of the five available products (including Letairis). Which ambrisentan product a health insurance plan covers may vary over time based on availability, so REMS participants may wish to speak with their PH-treating health care professional about also enrolling in the second REMS program, Parallel System (PS) Ambrisentan REMS, to allow maximum flexibility among various products.

Copay Assistance Programs
Patients prescribed either generic ambrisentan or Letairis can continue to receive copay assistance grants from nonprofit organizations as available. Copay assistance provided by the therapy manufacturer may vary by product and by state. Visit for more information.

Additional Resource
PHA continues to advocate for robust access to therapy allowing medical care to be driven by patients’ needs and clinicians’ judgments. The Pulmonary Hypertension Association’s (PHA’s) website provides information on financial assistance resources for PH therapy and  additional information patients and health care professionals may wish to discuss when considering a potential transition to generics.

Patients with questions about access to or the cost of ambrisentan therapy should contact their specialty pharmacy or PH care team. For more information about PHA’s Treatment Access Program, contact 301-565-3004 x749 or gro.noitaicossAHP@ecnarusnI.