For People with BOS & Family Page FAQ

Frequently Asked Questions (FAQ)

Breath Therapeutics, a Zambon company, is dedicated to developing innovative inhalation therapies to treat severe respiratory diseases. People living with rare lung diseases are at the center of everything we do. Our novel investigational drug-device combination is designed to deliver drug directly to the lungs.

Bronchiolitis obliterans syndrome (BOS), also known as obliterative bronchiolitis (OB), is a lung disease caused by inflammation that leads to scarring and narrowing of the small airways. In many cases, this condition can result in respiratory failure and death. BOS is most commonly seen in people who have had a lung transplant or allogeneic hematopoietic stem cell transplant (alloHSCT). BOS can also be associated with autoimmune diseases, lung infections, or exposure to environmental contaminants.

Currently, there are no approved treatments for BOS.  There is also no accepted or demonstrated standard-of-care for BOS.

Liposomal Cyclosporine A for Inhalation (L-CsA-i) is an investigational drug being studied to treat BOS.  Cyclosporine is a medicine that suppresses the immune system and reduces inflammation when taken by mouth or intravenously (IV).  L-CsA-i is an inhaled medicine given by a drug-specific Investigational eFlow® Technology nebulizer system (PARI Pharma GmbH). The inhaled approach allows L-CsA-i to be delivered directly to the lungs, the site of BOS.

We have five clinical studies that are currently ongoing or planned:

BOSTON-1 and BOSTON-2 are two ongoing global pivotal Phase 3 studies of adults with BOS following lung transplantation.

BOSTON‑3 is an open-label extension study for eligible study participants who complete BOSTON‑1 or BOSTON‑2

BOSTON-4 has been initiated in Germany, France and Spain for adults with BOS following alloHSCT.

BOSTON‑5 is a planned safety study in pediatric patients with BOS.

If you are interested in learning more about a clinical study, please go to as this is the easiest way to find a clinical research site near you.  You can contact the research team at the site, who will determine if you are a candidate for the study.

For more information on timelines and established centers, please see the links below.

BOSTON-1 (Single Lung Transplant) Identifier: NCT03657342

BOSTON-2 (Double Lung Transplant) Identifier: NCT03656926

BOSTON-3 (Open-label extension of BOSTON-1 and -2) Identifier: NCT04039347

BOSTON-4 (alloHSCT) Identifier: NCT04107675

Clinical studies are studies performed with people to examine new ways to prevent, detect, or treat disease. The purpose of clinical studies is to determine if a new medication or medical device works and if it is safe.  This is done before it is approved by the FDA (or equivalent) and made available for use by doctors.  With all clinical studies there may be no direct benefit to any one individual who participates in a study.

The United States Food and Drug Administration (FDA) has information on this subject.  Resources can be found via this link.

Expanded Access or Compassionate Use
At this time, Breath Therapeutics, a Zambon Company, is unable to provide unapproved medicines via expanded access or compassionate use and believes that participating in its ongoing or future clinical trials is the best way to access this medicine that is not yet approved by U.S. Food and Drug Administration. We have considered many factors, including our ability to maintain supply for the ongoing and planned clinical trials, enroll and complete ongoing and upcoming clinical trials, and make reasonable assessments of potential risk versus benefit for patients outside the clinical trial setting. In the event that Breath Therapeutics, a Zambon Company, decides to consider expanded access use for liposomal cyclosporine A for inhalation (L-CsA-i) in the future, we will evaluate and respond to each expanded access request on a case-by-case basis using criteria that ensures such requests are considered in a fair and consistent manner.

If you or a family member are/is interested in gaining access to our investigational therapy, we encourage you to consult with your physician regarding the possibility of participating in our clinical trial. For additional information about this posted policy or if you are a treating physician requesting expanded access, please contact us via email at We anticipate acknowledging receipt of such inquiries sent to this email within three business days.

The posting of this policy by Breath Therapeutics, a Zambon Company, shall not serve as a guarantee of access to any specific investigational drug by any individual patient. In accordance with the 21st Century Cures Act, Breath Therapeutics, a Zambon Company, may revise this expanded access policy at any time. The policy will be updated with a hyperlink or other reference to the expanded access record on after such record becomes active.

No, L-CsA-i is not an approved treatment and is only available through clinical studies.

If you have additional questions, please contact

Patient Resources:

There are many disease foundations, patient advocacy groups, and support groups at both the local and national level.  Your transplant care team can direct you to resources that are in your area.