Clinical trial results showed the RejuvenAir Metered CryoSpray solution significantly eases chronic lung symptoms and lowers severe hospital events.


RT’s Three Key Takeaways

  1. Clinically Meaningful Relief: Patients treated with Metered CryoSpray (MCS) achieved significant improvements in quality of life and respiratory symptoms at 12 months compared with a sham control, according to published clinical trial data.
  2. Fewer Severe Exacerbations: A supportive trial analysis revealed that patients receiving the procedure experienced a 38.4% relative reduction in severe flare-ups requiring hospitalization or emergency department visits more than 30 days after treatment.
  3. Acceptable Safety Profile: The primary procedural risk observed across the study was pneumothorax, occurring in 3.6% of procedures, with all instances resolving and no device- or procedure-related deaths reported.


A minimally-invasive bronchoscopic procedure that applies cold-spray therapy directly to diseased airways demonstrated significant clinical improvements in patients suffering from moderate-to-severe COPD and chronic bronchitis, according to clinical trial results published in AJRCCM.

The randomized, blinded, sham-controlled study evaluated the RejuvenAir Metered CryoSpray (MCS) therapy delivered via the RejuvenAir System across 210 patients in the US and the UK, according to CSA Medical. All participants remained highly symptomatic despite receiving optimal medical therapy prior to trial enrollment.

Primary Endpoints and Exacerbation Reduction

According to the published study data, the clinical trial successfully met its primary effectiveness endpoint at 12 months. Patients treated with MCS demonstrated a 5.9-point greater improvement on the St. George’s Respiratory Questionnaire (SGRQ) score compared with the control group (p=0.0422), exceeding the established 4-point threshold for clinically meaningful benefit. In addition, treated patients demonstrated a 3.4-point greater improvement on the COPD Assessment Test (CAT) score compared with control (p=0.005), surpassing the recognized 2-point threshold.

The company reported that MCS therapy was also linked to a reduction in severe COPD exacerbations, which frequently require emergency care, hospitalization, and intensive healthcare resources. In a supportive analysis evaluating severe exacerbations occurring more than 30 days after intervention, MCS-treated patients showed a 38.4% relative reduction in the incidence rate of severe events compared with control subjects.

“Patients enrolled in SPRAY-CB remained highly symptomatic despite receiving optimal medical therapy, underscoring the significant unmet need in chronic bronchitis,” said Gerard J Criner, MD, chair and professor of thoracic medicine and surgery at the Lewis Katz School of Medicine at Temple University and lead author of the study. “In this rigorous randomized, sham-controlled trial, Metered CryoSpray demonstrated clinically meaningful improvements in quality of life and overall COPD symptoms through 12 months. The findings, together with the lower incidence of severe COPD exacerbations observed with MCS, support the potential for a bronchoscopic therapy that directly targets the airways affected by chronic bronchitis to provide an important new treatment option for these patients.”

Safety Profile and Mechanism of Action

The clinical improvements were accompanied by an acceptable procedural safety profile, according to the trial investigators. The primary procedural risk was pneumothorax, which occurred in 3.6% of MCS procedures. The authors noted that all cases of pneumothorax resolved, none occurred following patient discharge, and the study recorded no unanticipated adverse device effects or device- or procedure-related deaths.

Unlike traditional pharmacological therapies that manage chronic bronchitis symptoms systemically, the RejuvenAir System delivers precisely measured doses of medical-grade liquid nitrogen directly to the airway lining during a bronchoscopic procedure, according to the manufacturer. This localized cold application is designed to trigger a nonscarring regenerative response, helping restore healthier airway epithelium, enhance mucociliary function, and reduce overall disease burden.

“The publication of the SPRAY-CB results represents the culmination of more than a decade of research, development and clinical investigation of RejuvenAir,” said Wendelin Maners, president and chief executive officer of CSA Medical. “These pivotal results support the potential for RejuvenAir to become the first interventional therapy developed specifically for chronic bronchitis and to establish an entirely new category of treatment for these patients.”