CSA Medical has raised $53m in Series D stock equity financing to advance the commercialisation of its RejuvenAir cryotherapy system for treating chronic bronchitis.

The proceeds are expected to fund the US Food and Drug Association (FDA) premarket approval (PMA) and the commercialisation strategy for the US launch of the RejuvenAir system.

The financiers included TVM Capital Life Science, Yonjin Ventures, SV Health Investors, Ascension Ventures, First Analysis, Blue Heron, and Intersouth Partners.

RejuvenAir is a cryospray that delivers liquid nitrogen via a radial head catheter to targeted areas within the lungs. It received a CE mark in Europe and breakthrough device designation and investigational device exemption (IDE) from the US Food and Drug Administration (FDA) in 2019.

The system is designed to induce a regenerative effect on endobronchial tissue, address the underlying cause of chronic bronchitis and enable a healing response in damaged cilia and mucus-producing goblet cells.

Chronic bronchitis is a type of chronic obstructive pulmonary disease (COPD) that is defined as a productive cough of more than three months occurring within two years. It is commonly as The World Health Organization (WHO) has identified COPD as the third leading cause of death worldwide, with the disease disproportionally affecting the elderly in low- and middle-income countries.

The Boston-based device developer is conducting a trial for the RejuvenAir system for chronic bronchitis. In July, CSA Medical announced that the pivotal SPRAY-CB trial (NCT03893370) for the RejuvenAir system had enrolled the planned 210 participants.

The primary endpoint of the sham-controlled trial is the improvement in overall patient health measured as the change in the St George Respiratory Questionnaire (SGRQ) score from baseline to 12 months. A low SGRQ score signifies better health. Secondary outcome measures include the reduction of cough and sputum at 12 months compared to baseline.