Rituximab Trial for Systemic Sclerosis-associated PAH Enrolling Participants

The National Institute of Allergy and Infectious Diseases is recruiting patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) to assess if Rituxan (rituximab) immunotherapy is effective against disease progression.

The randomized Phase 2 study, titled “Rituximab for Treatment of Systemic Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH),” is enrolling patients ages 18-75 who were diagnosed with of SSc-PAH within the past five years and have been treated with background medical therapy for PAH. Therapies could have included prostanoid, endothelin receptor antagonist, phosphodiesterase-5 inhibitors, or guanylate cyclase stimulators.

Eligible patients must be categorized in New York Heart Association (NYHA) Functional Class 2, 3, or 4, and must have been vaccinated with the pneumococcal vaccine within 5 years of study entry or been vaccinated at least one month prior to starting treatment.

The randomized, double-blind, placebo-controlled Phase 2 trial will be conducted at 26 locations in the U.S. The study is expected to be complete in January 2019.

There is no current cure for SSc-PAH, and treatment is limited to PAH-specific drugs that induce dilation of blood vessels. Recent studies have reported that immunotherapy may also help treat patients with SSc associated with interstitial lung diseases in addition to anecdotal and pretrial reports that it benefits SSc-PAH patients.

To test this hypothesis, the trial will enroll up to 60 SSc-PAH patients who will receive either 1,000 mg of Rituxan or placebo in two intravenous infusions given two weeks apart. The study’s primary outcome is change in pulmonary vascular resistance measured by right heart catheterization. The secondary outcome measures will include Rituxan safety and tolerability, time to clinical worsening, number of new digital ulcers, exercise capacity determined by the 6-minute walking distance test, change in quality of life, and other impacts.

The trial will also include a sub-study titled “Right Ventricular Response to Rituximab in Systemic Sclerosis-Associated Pulmonary Arterial Hypertension – A Magnetic Resonance Imaging Sub-study,” also called the RESTORE Sub-study. The study will evaluate the therapeutic effect of Rituxan on the right ventricle of patients with SSc-PAH. Right ventricle function and prognosis will be assessed through changes in right ventricular end diastolic volume index and stroke volume , as observed by cardiac magnetic resonance imaging (MRI).

For the RESTORE study, 20 patients from each group in the main study will be studied at baseline and after 24 weeks or at the time of discontinuation. In addition to enrollment criteria of the main study, patients in the sub-trial cannot show hypersensitivity to gadolinium, be unable to tolerate MRI, should not have morbid obesity, or have metallic objects or pacemakers implanted in their bodies.

For more information about the clinical trial and how to participate, visit this link.