by Phyllis Hanlon, Contributing Writer

The Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL registry) is a study of approximately 3,500 people with World Health Organization (WHO) Group 1 pulmonary hypertension (pulmonary arterial hypertension, or PAH) in the U.S. Study participants who were followed 2006-2011 contributed important information to the pulmonary hypertension (PH) community that allowed for a better understanding of what makes a person more likely to get PH, how PH is treated and longer-term outcomes. One of the products of the REVEAL registry is a risk calculator that calculates a patient’s REVEAL risk score, which is used by many clinicians to identify patients with a higher mortality risk.

At its creation, the REVEAL risk calculator used 12 factors about a patient (e.g., the six-minute walk distance, or 6-MWD) that provided a REVEAL risk score ranging from zero (lowest risk) to 22 (highest risk). Scores are typically grouped into low-risk (score one to seven), average-risk (eight), moderately high-risk (nine), high risk (10 or 11) and very high risk (12 or greater) patients. Although the calculator was initially designed to measure a specific point in time, researchers later showed that changes in REVEAL risk score could reflect changes in a patient’s risk, thus allowing clinicians to monitor a patient’s response to treatment and risk over time.

In 2017, researchers conducted a study to apply the REVEAL risk score to data for an already completed clinical trial: riociguat (PATENT-1 and PATENT-2 clinical trials). The researchers wanted to test whether the REVEAL risk score of a participant in the clinical trial was associated with signs of the patient getting worse and if treatment with riociguat improved a patent’s REVEAL risk score.

PATENT-1 was a 12-week clinical trial of riociguat. Following the 12-week PATENT-1 study, most patients enrolled in the follow-up study, PATENT-2, which followed patients for two additional years to learn more about how the drug works.

Raymond L. Benza, M.D., led this study, which included specialists from Pulmonary Hypertension Association (PHA) accredited Pulmonary Hypertension Care Centers (PHCC) at Allegheny General Hospital, Houston Methodist Hospital and Weill Cornell Medical College.

Dr. Benza and his colleagues reviewed data on 396 patients who had completed the PATENT-1 trial of riociguat; the results showed that patients who took riociguat significantly decreased their REVEAL risk score at week 12 when compared to those taken at the beginning of the study. Dr. Benza explained that a lower REVEAL risk score signifies a better outcome. The patients from PATENT-1 who took riociguat and went on to participate in the PATENT-2 study continued to experience positive results, according to the authors. They noted that those patients who received a placebo (inactive drug) in PATENT-1 and enrolled in PATENT-2 were given riociguat. These patients also experienced improvements similar to those experienced by the patients who were assigned to take riociguat PATENT-1.

The authors noted that these findings are important primarily because they confirm the ability of the REVEAL risk score to correlate with survival in a well-controlled setting of PAH patients. This enhances practitioners’ confidence to use the REVEAL risk score to predict survival in their PAH patients and establish the aggressiveness of their therapy, based on an individual patient’s risk. According to Dr. Benza, the REVEAL risk score provides a guide to their doctors to make sure the treatment matches the risk of the disease getting worse.