Open-Label Extension Study for Subjects With H1 Antihistamine Refractory Chronic Spontaneous Urticaria Completing Study AK006-001

An Open-Label Extension Study Evaluating the Safety, Tolerability, PK, Immunogenicity, and Clinical Response of Multiple Doses of IV AK006 in Subjects With H1 Antihistamine Refractory Chronic Spontaneous Urticaria Completing Study AK006-001

An open label extension (OLE) study offered to subjects with Chronic Spontaneous Urticaria that have completed the AK006-001 (NCT06072157) Part C referred to as the Main study portion of the study. Qualified subjects will receive up to four doses of the study drug (AK006) through an intravenous infusion every 4 weeks. There is a 16-week follow up period once all the scheduled infusions have been completed. Subjects will be follow for evaluation of safety, tolerability, PK, immunogenicity, and clinical response.

Study Overview

• Status: Completed
• Conditions: Chronic Spontaneous Urticaria
• Intervention / Treatment: Drug: AK006 IV

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Phase 1

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2M 1A6
      • Site 601-106
  • Ontario
    • Niagara Falls, Ontario, Canada, L2H 1H5
      • Site 601-107
    • Toronto, Ontario, Canada, M5G 1E2
      • Site 601-108
  • Quebec
    • Québec, Quebec, Canada, G1V 4W2
      • Site 601-102
    • Québec, Quebec, Canada, G1W 4R4
      • Site 601-105
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35209
      • Site 601-004
  • California
    • Bakersfield, California, United States, 93301
      • Site 601-014
    • Upland, California, United States, 91786
      • Site 601-015
  • Kansas
    • Overland Park, Kansas, United States, 66211
      • Site 601-006
  • Kentucky
    • Lexington, Kentucky, United States, 40509
      • Site 601-019
  • Missouri
    • St Louis, Missouri, United States, 63141
      • Site 601-011
  • Ohio
    • Cincinnati, Ohio, United States, 45236
      • Site 601-002
  • Texas
    • El Paso, Texas, United States, 79912
      • Site 601-010
  • Wisconsin
    • Greenfield, Wisconsin, United States, 53228
      • Site 601-013

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

• Enrolled in Part C of Study AK006-001 (NCT06072157) and completed the randomized, double-blind, placebo-controlled treatment period and the Day 99 Visit.
• Acceptable demonstration of tolerance to study drug during the AK006-001 study as determined by the investigator.
• Acceptable demonstration of protocol compliance during the AK006-001 study as determined by the investigator.
• Female subject of childbearing potential and male subject with female partner of childbearing potential must agree to use a highly effective method of contraception with <1% failure rate or abstain from sexual activity from Screening until the end of the study, or for 16 weeks following the last dose of AK006, whichever is longer.

Key Exclusion Criteria:

• Pregnant, breastfeeding, or planning to become pregnant while participating in the study.
• Planned use of an approved or investigational therapy to treat CSU other than a single 2nd- or later-generation H1-AH between 1× and 4× the licensed dose and frequency, during the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 720mg of AK006 IV; Subjects in this arm will receive 4 doses of 720mg of AK006 via intravenous infusion every 4 weeks.	Drug: AK006 IV; Formulation for intravenous infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Incidence of adverse events (AEs), treatment-emergent adverse events, serious adverse events, adverse events of special interest, AEs leading to discontinuation	Through study completion, approximately 30 weeks
Incidence of clinically significant abnormal laboratory values, ECGs, and vital signs	Through study completion, approximately 30 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
AK006 serum concentrations		Through study completion, approximately 30 weeks
AK006 Anti-drug Antibodies (ADAs)	Number of participants with positive or negative AK006-ADAs.	Through study completion, approximately 30 weeks

Collaborators and Investigators

• Sponsor: Allakos Inc.
• Investigators: Study Director: Chin Lee, MD, MPH, Allakos Inc.

Study record dates

Study Major Dates

• Study Start (Actual): August 28, 2024
• Primary Completion (Actual): May 21, 2025
• Study Completion (Actual): May 21, 2025

Study Registration Dates

• First Submitted: August 27, 2024
• First Submitted That Met QC Criteria: August 27, 2024
• First Posted (Actual): August 29, 2024

Study Record Updates

• Last Update Posted (Estimated): August 27, 2025
• Last Update Submitted That Met QC Criteria: August 26, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Chronic Disease; Disease Attributes; Immune System Diseases; Hypersensitivity, Immediate; Hypersensitivity; Skin Diseases; Urticaria; Skin Diseases, Vascular; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Chronic Urticaria
• Other Study ID Numbers: AK006-001X

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No