Objective: To evaluate the efficacy and tolerability of prolonged administration of quinapril, a long-acting angiotensin-converting enzyme inhibitor, in the management of the peripheral vascular manifestations of limited cutaneous systemic sclerosis (lcSSc) and in the prevention of the progression of visceral organ involvement in the disease.
Methods: This was a multicenter, randomized, double-blind, placebo-controlled study evaluating quinapril 80 mg/day, or the maximum tolerated dosage, in 210 patients with lcSSc or with Raynaud's phenomenon (RP) and the presence of SSc-specific antinuclear antibodies. Treatment was for 2-3 years. The primary outcome measure was the number of new ischemic ulcers appearing on the hands; secondary measures were the frequency and severity of RP attacks, skin score, treatments for ischemia, health status (measured by the Short Form 36 instrument), measures of kidney and lung function, and echocardiographic estimates of pulmonary artery pressure. An intent-to-treat analysis was used.
Results: Quinapril did not affect the occurrence of digital ulcers or the frequency or severity of RP episodes. It did not alter the treatments that were prescribed for either infected ulcers or severe RP symptoms. There was no apparent effect on the estimated tricuspid gradient. Health status was not affected by quinapril, and one-half of the patients who believed they had benefited from the trial treatment were in the placebo arm. Quinapril was not tolerated by one-fifth of the patients, with dry cough being the most frequent side effect.
Conclusion: Administration of quinapril for up to 3 years had no demonstrable effects on the occurrence of upper limb digital ulcers or on other vascular manifestations of lcSSc in this patient population.