Why Is It Such a Challenge to Treat PAH?

Pulmonary arterial hypertension (PAH) is a life-threatening, degenerative disease that severely compromises the function of both the pulmonary (lung) and cardiovascular (heart) systems. Blood flow in the arteries becomes restricted which results in increased blood pressure, reducing the red blood cells’ capacity to absorb or transport oxygen to the heart.  Symptoms include shortness of breath, fatigue, chest pain, dizzy spells, and fainting, but severe heart failure from PAH can result in death - with recent studies estimating a five-year survival rate of about 57%[i].

Despite current treatment options in PAH offering improvements in symptom control and quality of life factors, there continue to be significant challenges that compromise the effective management of this progressive and debilitating condition.

In most western markets, the medical care of PAH patients typically falls under the responsibility of cardiologists and pulmonologists working within specialised pulmonary hypertension (PH) clinics/departments.  In a recent online forum conducted by Ipsos[ii], a group of managing physicians discussed some of the key challenges limiting their ability to provide optimum care; factors ranged from late patient referral and misdiagnosis, poor treatment outcomes and limited treatment guidelines.

With common problems like fatigue, chest pain, dizzy spells or fainting identified as the primary symptoms of PAH, there are inevitably delays in treatment due to misdiagnosis.  Within the primary care setting, PAH - with its orphan disease status - is not top of mind.  Therefore, it is often not until a patient is correctly referred to a specialist cardiologist, with access to echocardiograms and angiograms, that a diagnosis can be confirmed. Physicians report that this process can take months if not years, hindering long-term treatment outcomes as patients develop more severe symptoms. Educating primary care and non-specialist physicians to recognise and diagnose PAH earlier would enable patients to be fast-tracked towards the specialised care they need.

The current guidelines (ASC and ESC) have a limited role in the management of PAH - they are typically perceived to be too universal and also dated.  As in many therapeutic areas, patients do not necessarily fit neatly into the category set up by the guidelines, so physicians rely on personal experience and knowledge of the underlying disease to make treatment decisions as symptoms change and progress.  

Irrespective of guidelines, it is also very difficult for physicians to predict whether patients will respond favourably to the treatments available.  In some markets, physicians receive support/advice from their peers with more complex cases but in many markets this type of ‘community network’ is not available.  For physicians managing patients failing on treatment, this represents a particularly challenging time.  Support programmes offering guidance on treatment goals and tailored treatment approaches for PAH patients, by aetiology and functional class, would be beneficial to physicians to aid long-term management in the future.

There are currently four classes of drugs available to treat PAH (PDE5-i, ERA, prostacyclin and sGC), all aimed at relaxing the walls of the pulmonary arteries to reduce blood pressure.  All classes now have more convenient oral administrations available and some of the most recently launched brands offer better efficacy and tolerability profiles.  However, treatments that are targeted towards symptomatic relief, rather than cure, hold a significant annual price tag - up to as much as $100,000 USD, a cost which can at least double for a patient reliant on a combination regimen.  Some funding bodies find this difficult to justify.  As a result, it is not surprising that physicians report facing road blocks and significant red tape in gaining approval to prescribe, with regular prescription renewals adding to the burden of an already debilitating disease.

The future for PAH treatment shows a move towards the use of combination therapies and more convenient modes of administration, but it is evident from our research into the daily challenges of treating patients with PAH that there are still many system and functional improvements that can be made in order to effectively manage this disease.

[i]REVEAL: a contemporary US pulmonary arterial hypertension registry; McGoon MD, Miller DP, European Respiratory Review

http://err.ersjournals.com/content/21/123/8.full?ijkey=1f8b71180dfa5097b4e1e51ee1350d729a2405ad&keytype2=tf_ipsecsha

[ii] Ipsos PAH CommuityVoice; panel of 115 physicians from US and EU5; conducted during November-December 2015