Sotatercept for Pulmonary Arterial Hypertension Patients

A New Ray of Hope

Pulmonary arterial hypertension (PAH) is a rare, progressive disease characterised by the thickening of pulmonary artery walls, causing increased resistance and pressure that makes it difficult for the heart to pump blood to the lungs. This leads to symptoms such as shortness of breath, fatigue, chest pain, and dizziness and can result in right ventricle dysfunction and premature death. This article explores the Final Evidence Report assessing the comparative clinical effectiveness and value of sotatercept from The Institute for Clinical and Economic Review (ICER).

Understanding PAH:

PAH significantly impacts patients financially, with costs exceeding $100,000 per person annually. The disease affects 50,000 to 100,000 people in the US, typically between the ages of 30 and 60, and is more common in women. PAH can be idiopathic, inherited, or associated with exposure to certain substances or conditions. The disease severely impacts the quality of life, particularly in physical function domains. One-fifth of PAH patients die within three years after diagnosis, significantly reducing lifespan. 

Current PAH Treatment Landscape:

Current treatment for PAH includes medications that promote vasodilation with the goals of improving functional status and survival. However, these treatments can be burdensome, and often have to be used in multiple combination therapies. Despite treatment many cases will inevitably be referred for lung or heart-lung transplantation.

Sotatercept for PAH treatment:

Sotatercept (Merck & Co., Inc) is a first-in-class activin signaling inhibitor and potentially disease-modifying drug. It is administered as a subcutaneous injection every three weeks and has been shown to improve pulmonary blood flow. The US Food and Drug Administration (FDA) has received a request for sotatercept, with a decision anticipated by March 26, 2024.

The STELLAR Trial:

The pivotal trial for sotatercept was STELLAR, a Phase III randomised, placebo-controlled trial based on 323 cases of PAH. The results showed that treatment with sotatercept added to background therapy can improve clinical outcomes for patients with PAH. The risk of clinical deterioration or death dropped 84%. Side effects of sotatercept included a considerable increase in telangiectasias, haemoglobin levels, and bleeding.

Economic impact:

The exact cost of sotatercept is still unknown. However, it is estimated that, if priced within the health benefit pricing benchmark (HBPB) range, all suitable patients could be treated with sotatercept over a five-year period without causing significant budget issues. ICER used a de novo decision analytic model to analyse the cost-effectiveness of adding sotatercept to background therapy in the health care sector. Sotatercept treatment led to increased symptom-free time at rest, quality-adjusted life years, and equal value life years. HBPB for sotatercept ranges from $17,900 to $35,400 annually as per the report.