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A Study to Demonstrate How Well REGN1908-1909 Works in Reducing Ocular Allergy Signs and Symptoms in Adult Participants With Cat Allergy

Phase 3
Recruiting
Conditions
Allergic Conjunctivitis
Interventions
Drug: REGN1908
Drug: Placebo
Drug: REGN1909
Registration Number
NCT06602726
Lead Sponsor
Regeneron Pharmaceuticals
Brief Summary

This study is researching 2 experimental drugs, REGN1908 and REGN1909, which are called REGN1908-1909 when mixed together (called "study drug") to reduce eye allergy signs and symptoms from cat allergy.

The aim of the study is to see how safe and effective the study drug is at lowering allergic eye signs and symptoms compared with placebo. A placebo looks like a treatment but does not contain any real medicine.

The study is looking at several other research questions, including:

* What side effects may happen from taking the study drug

* How much study drug is in the blood at different times

* Whether the body makes antibodies against the study drug (which could make the drug less effective or could lead to side effects)

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
70
Inclusion Criteria
  1. Documented or participant-reported history of moderate to severe cat allergy for at least 2 years with bothersome ocular symptoms being near cat(s)
  2. Positive SPT with cat allergen extract (mean wheal diameter at least 5 mm greater than the negative control) at screening visit 1
  3. Positive Allergen-specific Immunoglobulin E (sIgE) tests for cat allergen and Fel d 1 (both ≥0.7 kUa/L) at screening visit 1
  4. Must be able to complete the screening CACs to confirm moderate to severe cat allergen-induced allergic conjunctivitis as described in the protocol
  5. Must not have lived with a cat(s) in the home for the past 3 years and must be willing to have no exposure to cat(s) at home throughout the study duration as described in the protocol

Key

Exclusion Criteria
  1. Participation in a prior clinical study and received either REGN1908-1909, REGN1908, or REGN1909 antibodies as described in the protocol
  2. Inability to complete or termination of the screening or confirmatory CAC (where applicable) due to a safety concern (eg, anaphylaxis), per PI judgement
  3. Significant and/or severe allergies, ocular, nasal, or systemic disease causing symptoms (eg, ocular itching, ocular redness, etc) that are expected to coincide or potentially interfere with the study CAC assessments, as described in the protocol
  4. Persistent chronic or recurring acute infection requiring treatment with systemic antibiotics, antivirals, or antifungals, or any untreated respiratory infections within 4 weeks prior to screening visit 1 as described in the protocol
  5. Presence of ocular conditions associated with acute or chronic vision loss, or any other ophthalmic disease or abnormality that may affect the study outcomes or participant safety, per Principal Investigator (PI) judgement as described in the protocol
  6. Uncontrolled asthma or on Global Initiative for Asthma (GINA) steps 4 to 5 as described in the protocol
  7. Abnormal lung function as judged by the investigator with Forced expiratory volume in 1 second (FEV1) <70% of predicted at screening
  8. History of cat immunotherapy (eg, subcutaneous immunotherapy or any other route) in the 3 years prior to screening visit 1
  9. Ongoing Allergen immunotherapy (AIT) with any allergen other than cat at screening visit 1 as described in the protocol

Note: Other Protocol Defined Inclusion/ Exclusion Criteria Apply

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
REGN1908-1909REGN1908-
REGN1908-1909REGN1909-
PlaceboPlacebo-
Primary Outcome Measures
NameTimeMethod
Ocular itch scoreAt day 8 post-Conjunctival Allergen Challenge (CAC)

Assessed using the Ora Calibra® Conjunctival Allergen Challenge Ocular Itching Scale, a 0-4 point scale where 0= none and 4= incapacitating itch, 0.5 unit increments

Secondary Outcome Measures
NameTimeMethod
Conjunctival redness scoreAt day 8 post-CAC

Assessed using the Ora Calibra® Hyperemia Scale (for conjunctival \[conjunctival redness scale\], ciliary \[ciliary redness scale\] and episcleral \[episcleral redness scale\] vessel beds), a 0 to 4 point scale, where 0 = none and 4 = extremely severe, 0.5 unit increments

Percent change in cat titrated Skin prick test (tSPT)Baseline and day 8

Area under the curve (AUC) of the mean wheal diameters

Tearing scoreAt day 8 post-CAC

Assessed using the Ora Calibra® Conjunctival Allergen Challenge Tearing Scale, a 0-4 scale where 0 = none and 4 = very severe, 1 unit increments

Total Ocular Symptom Score (TOSS)At day 8 post-CAC

TOSS is a summed score of ocular itch score (graded 0 = none to 4 = incapacitating itch), conjunctival redness score (graded 0 = none to 4 = extremely severe), and tearing score (graded 0 = none to 4 = very severe) for a total range from 0 to 12, where higher scores indicate worse responses

Total redness scoreAt day 8 post-CAC

The total redness score is calculated for CAC: range 0 to 12, where higher scores indicate worse responses (calculated as a sum of the bilateral averages for conjunctival redness score, graded 0 = none to 4 = extremely severe + ciliary redness score, graded 0 = none and 4 = extremely severe + episcleral redness score, graded 0 = none and 4 = extremely severe)

Ciliary redness scoreAt day 8 post-CAC

Assessed using the Ora Calibra® Hyperemia Scale (for conjunctival \[conjunctival redness scale\], ciliary \[ciliary redness scale\] and episcleral \[episcleral redness scale\] vessel beds), a 0 to 4 point scale, where 0 = none and 4 = extremely severe, 0.5 unit increments

Episcleral redness scoreAt day 8 post-CAC

Assessed using the Ora Calibra® Hyperemia Scale (for conjunctival \[conjunctival redness scale\], ciliary \[ciliary redness scale\] and episcleral \[episcleral redness scale\] vessel beds), a 0 to 4 point scale, where 0 = none and 4 = extremely severe, 0.5 unit increments

Change in cat tSPTBaseline and day 113

AUC of the mean wheal diameters

Percent change in cat tSPTBaseline and day 113

AUC of the mean wheal diameters

Incidence of Treatment-emergent adverse events (TEAEs)Up to Day 113
Severity of TEAEsUp to Day 113
Incidence of serious TEAEsUp to Day 113
Incidence of Adverse event of special interest (AESIs)Up to Day 113
Total REGN1908 concentrations in serum over timeUp to Day 113
Total REGN1909 concentrations in serum over timeUp to Day 113
Incidence of Anti-drug antibodies (ADAs) to REGN1908Up to Day 113
Titers of ADAs to REGN1908Up to Day 113
Incidence of ADAs to REGN1909Up to Day 113
Titers of ADAs to REGN1909Up to Day 113

Trial Locations

Locations (4)

Kingston Health Sciences Centre

🇨🇦

Kingston, Ontario, Canada

Red Maple Trials Inc.

🇨🇦

Ottawa, Ontario, Canada

Clinique de Specialisee en Allergie de la Capitale

🇨🇦

Quebec, Canada

Andover Eye Associates

🇺🇸

Andover, Massachusetts, United States

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