Help us take a closer look at managing HAE

We are enrolling participants who have been diagnosed with hereditary angioedema (HAE) type I or type II for a clinical research study called the HAE CHAPTER-1 Study. This clinical research study is evaluating an investigational medication called PHVS416 that is a potential oral treatment option which may prevent HAE attacks.

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About the HAE CHAPTER-1 Study

Participation in the HAE CHAPTER-1 Study can last up to 22 weeks. During this time, participants will have study visits over three periods: screening, treatment, and the end-of-study visit. Some of these visits may occur remotely.

Screening

This period lasts up to eight weeks. During this period, participants will be evaluated to see if the study is a good match for them.

Treatment

This period lasts 12 weeks. During this period, participants will receive either PHVS416 or the placebo (an inactive drug that looks just like PHVS416 but does not contain active ingredients). Some of these visits may be performed remotely.

End-of-Study Visit

This visit happens after the treatment period ends. During this visit, the study team performs final assessments to check on participants’ health after they have stopped taking PHVS416 or placebo.

Open-Label Extension

Participants who enroll in the HAE CHAPTER-1 Study and complete the treatment period may be eligible to enroll in an open-label extension study and receive PHVS416.

About PHVS416

A low level of the C1-inhibitor in the blood causes an increased amount of the protein bradykinin, which causes the painful symptoms of HAE swellings. PHVS416 is designed to attempt to prevent some of the effects of bradykinin, which may prevent HAE swellings (acute attacks).

In this clinical research study, PHVS416 is a softgel capsule taken orally that is being compared to a placebo. A placebo is an inactive drug that looks just like the investigational medication being studied but contains no active ingredients. The placebo allows researchers to fully understand the effects of the investigational medication.

Two capsules of PHVS416 or placebo are taken by mouth twice daily after breakfast and dinner. Participants will be chosen at random to receive the low dose of PHVS416 (one capsule of PHVS416 and one capsule of placebo), the high dose of PHVS416 (two capsules of PHVS416), or the placebo (two capsules of placebo). Neither participants nor the study doctor will know which study treatment has been assigned, but in case of an emergency, the study doctor can find out.

After completing participation in the HAE CHAPTER-1 Study, participants may be eligible to enroll in an open-label extension study and receive PHVS416.

Who may qualify

Eligible participants must:

  • Be male or female adults 18 to 75 years old
  • Have a diagnosis of HAE (type I or type II)
  • Have had at least three HAE attacks within the last three months
    • If the patient has no documentation of attack history or has fewer than three attacks in the three months before the screening visit, or was on prophylactic treatment, the patient must experience a minimum of two qualifying HAE attacks during the screening period (up to eight weeks)
  • Be willing to stop taking any current medications for HAE prevention

Other eligibility criteria apply. Interested individuals will be evaluated during the screening period to make sure they are eligible to participate. PHVS416 (or placebo) and study-related assessments will be provided at no cost. Participants will also be eligible for reimbursement for other expenses related to the study, such as travel and HAE standard-of-care medication.

Active site locations

Future site locations

About hereditary angioedema

Hereditary angioedema (HAE) is a rare genetic condition, and the symptoms and frequency of attacks may vary from person to person. Some people may get a rash or experience a tingling sensation in a specific area of the body before their HAE attack. Generally, HAE attacks cause swelling in the skin, abdomen, and throat.

Minor stress or trauma may bring on an attack, but swelling often occurs without a known trigger. HAE is often initially misdiagnosed as an allergic reaction, but medications such as epinephrine, glucocorticoids, and antihistamines don’t reduce the swelling associated with HAE attacks.

Reference: haei.org/hae/

An adult blowing bubbles together with a child. The bubbles in the foreground magnify areas of the adult's face and hands to represent swelling from HAE.

About clinical research studies

What is a clinical research study?

Clinical research studies, also called clinical trials, look at an investigational medication or medical device to see if it is safe, how it works in the body, and if it works to treat a specific disease. Clinical research studies are conducted by doctors who are responsible for the study participants’ study-related care.

In most countries, the regulatory health authority, such as the Food and Drug Administration (FDA) in the United States and the European Medicines Agency (EMA) in the European Union, requires that several phases of clinical research be performed to better understand the safety and efficacy of new investigational medications and certain medical devices.

Clinical research studies must be approved by an institutional review board (IRB) or ethics committee (EC). An IRB/EC is a group that is responsible for securing the rights and welfare of study participants. In addition, every study participant is monitored with study-related medical tests and exams before, during, and sometimes even after the study.

Can a participant leave the study if they change their mind?

Participation in any clinical research study is completely voluntary, and participants may choose to leave the study at any time for any reason. Before leaving the study, participants should discuss this decision with the study doctor, who will give them information about how to do this safely.

What should participants expect?

Before an individual can take part in the HAE CHAPTER-1 Study, they will first need to attend the screening visit(s) for initial tests and assessments to see if they are eligible to participate. After all necessary tests and assessments have been completed, and if an individual is eligible to participate, they may enter the study and receive the assigned study treatment.

How long will study participation last?

Participation in the HAE CHAPTER-1 Study can last up to 22 weeks.

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For physicians

Study purpose

The HAE CHAPTER-1 Study is assessing the safety and efficacy of PHVS416 in preventing hereditary angioedema (HAE) attacks in people with HAE type I or type II.

Study periods

The total duration of participation can last up to 22 weeks, including a screening period that can last up to 8 weeks, a 12-week treatment period, and an end-of-study visit 2 weeks after the treatment period ends. Participants will have some visits on-site at the study clinic, while other visits may be performed remotely.

About PHVS416

In this clinical research study, PHVS416 is a softgel capsule taken orally that is being compared to a placebo. This is a double-blind study, and participants will be randomized to receive the low dose of PHVS416 (one capsule of PHVS416 and one capsule of placebo), the high dose of PHVS416 (two capsules of PHVS416), or the placebo (two capsules of placebo). Two capsules of PHVS416 or placebo are taken by mouth twice daily after breakfast and dinner.

PHVS416 attempts to address the increased amount of the protein bradykinin in people with HAE. In most cases, people with HAE have a genetic defect in the C1-inhibitor, causing a biochemical imbalance with increased amounts of bradykinin. This bradykinin increase leads to the painful swelling that occurs with HAE attacks. PHVS416 is designed to attempt to prevent some of the effects of bradykinin, which may prevent HAE swelling attacks.

Key eligibility criteria

Inclusion criteria

  • Signed and dated informed consent form
  • Diagnosis of HAE type I or II
  • Documented history of at least 3 HAE attacks within the last 3 consecutive months prior to screening
    • If the patient has no documentation or has less than 3 attacks in the 3 months before the screening visit, or was on prophylactic treatment, patient must experience a minimum of 2 HAE attacks during the screening period (up to 8 weeks)
  • Reliable access and experience to use standard-of-care acute attack medications

Other inclusion and exclusion criteria apply. For additional information, visit ClinicalTrials.gov.

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Exclusion criteria

  • Pregnancy or breast-feeding
  • Clinically significant abnormal electrocardiogram
  • Any other systemic disease or significant disease or disorder that would interfere with the patient’s safety or ability to participate in the study
  • Patient is receiving prophylactic treatment for HAE
    • Patients who have previously received prophylactic therapy but have stopped can participate in this study provided a sufficiently long washout period is observed before the patient is screened
  • Use of C1-esterase inhibitor, oral kallikrein inhibitors, attenuated androgens, anti-fibrinolytics, or monoclonal HAE therapy within a defined period prior to enrollment
  • Abnormal hepatic function
  • Abnormal renal function
  • History of alcohol or drug abuse within a defined period, or current evidence of substance dependence or abuse
  • History of documented severe hypersensitivity to any medicinal product
  • Participation in any other investigational drug study within a defined period

Other inclusion and exclusion criteria apply. For additional information, visit ClinicalTrials.gov.

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