(BPT) - In the U.S., about 7,000 people live with hereditary angioedema, or HAE,^1,2 a rare condition that results in unpredictable swelling attacks.^3-8 Symptoms often appear early in life and can worsen over time.⁸

The swelling attacks can cause arms and hands, legs and feet, belly, genitals, face, or throat (airways) to swell,^5,6,9 sometimes resulting in difficulty breathing and, in severe cases, suffocation (asphyxiation).^7-9 Attacks can be triggered by physical trauma, such as dental work, or emotional stress (for example finals week), and even occur without a known trigger.^5-9 Attacks can last for several days if not treated.¹⁰

Living with HAE can be challenging. The unpredictable nature of attacks can significantly impact a person's quality of life, creating anxiety, fear, and even embarrassment.^3,5,7,8,11

"Living with HAE is like having your life put on hold constantly; feeling you have no control, not even on the simplest of things, not knowing when your plans are going to be interrupted," said Soraya Alvarez Diaz, who had her first HAE attack as a child, "it is physically and emotionally exhausting and can make you feel isolated."

"An attack can occur at any time or in any occasion. I even had a severe laryngeal attack on a plane while traveling to New York. It was one of the scariest moments of my life," she said.

Currently, there is no cure, but there are treatments available that can prevent or manage the symptoms of an attack. Nonetheless, unmet treatment needs remain, including the need for additional oral medicines that are effective, well-tolerated, convenient, discreet, and portable.

One company working to address those needs is Pharvaris, which is developing a potential new treatment to further address the unmet medical needs for people living with HAE.

Investigating attack prevention: the CHAPTER-4 study^12,13

The CHAPTER-4 study is a long-term, open-label study investigating Pharvaris' investigational drug, deucrictibant, an extended-release tablet for the preventative treatment of HAE attacks in adolescents and adults, ages 12 and above.

Deucrictibant has already been tested in other HAE clinical research studies, the results of which have supported further development/study, and it has shown favorable results for efficacy and safety.

Why take part in a clinical study?

Clinical studies have been, and continue to be, essential to eventually bringing new treatments to those who need them.

"For me, the main reason to participate in clinical trials, and the reason I believe others should consider doing the same, is the chance to contribute to the development of new medications to treat HAE," said Alvarez Diaz, "I have a sense of satisfaction knowing that I have contributed to help others in need."

New therapies may offer people with HAE the opportunity to further improve management of their condition and, given the hereditary nature of HAE, experience fewer unmet medical needs than previous generations.

Participating in a clinical study can be a valuable experience. Studies can represent a form of access to investigational drugs in development that may not be available outside of a study and allow participants to contribute to the advancement of medical knowledge.

"Medical breakthroughs and advances require the active participation and support of the scientific community, including patients, suffering from the conditions," said Alvarez Diaz. "Others have led the way in benefit of humankind. I do not want to be just part of the problem; I want to be part of the solution. Participating in clinical trials can help build a better future for new generations of patients, as others did for me."

Curious to find out more?

If you or a loved one are interested in learning more about the CHAPTER-4 study, please visit: https://hae-chapter.com/#about-ch4-study

Currently, deucrictibant is only available in an investigational setting as a drug currently being studied for the prevention, or treatment, of HAE attacks. Deucrictibant is an investigational product and has not been approved by the FDA for the prevention or treatment of HAE.

References

1. Castaldo AJ, et al. Ann Allergy Asthma Immunol. 2025;135(3):303-310.
2. Lumry WR. Front. Med. 2018; 5:22.
3. Lumry WR, et al. Allergy Asthma Proc. 2020;41(Suppl 1):S08-S13.
4. Christiansen SC, et al. Ann Allergy Asthma Immunol. 2023;131(6):766-774.e8.
5. Maurer M, et al. Allergy. 2022;77(7):1961-1990.
6. Betschel SD, et al. J Allergy Clin Immunol Pract. 2023;11(8):2315-2325.
7. Busse PJ et al. J Allergy Clin Immunol Pract. 2021;10(3):716-717.
8. FDA CBER, The voice of the patient - Hereditary angioedema. May 2018. https://www.fda.gov/files/about%20fda/published/The-Voice-of-the-Patient---Hereditary-Angioedema.pdf. Accessed February 9, 2026.
9. US Hereditary Angioedema Association. What is Hereditary Angioedema (HAE)? https://www.haea.org/pages/p/what_is_hae. Accessed February 9, 2026.
10. Bork K, et al. Allergy Asthma Clin Immunol. 2021;17(1):40.
11. Anderson J, et al. Allergy Asthma Clin Immunol. 2021;17(1):60.
12. CHAPTER-3. Join us. https://hae-chapter.com/. Accessed February 9, 2026.
13. Long-Term, Open-label Study of Oral Deucrictibant Extended-Release Tablet for Prophylaxis Against Angioedema Attacks in Adolescents and Adults With HAE (CHAPTER-4). 2025. ClinicalTrials.Gov NCT06679881. https://clinicaltrials.gov/study/NCT06679881. Accessed February 9, 2026.