A Phase 2 Study to Evaluate Axatilimab for Hospitalized Participants With Respiratory Involvement Secondary to COVID-19

Phase 2

Terminated

• Conditions: COVID; Cytokine Storm; Cytokine Release Syndrome; Coronavirus; ARDS
• Interventions: Drug: SNDX-6352; Drug: Placebo

• Registration Number: NCT04415073
• Lead Sponsor: Syndax Pharmaceuticals

Brief Summary

This was a randomized, double-blind, placebo-controlled, 29-day study to assess the efficacy and safety of axatilimab plus standard of care (SOC), compared with placebo plus SOC, in participants with respiratory signs and symptoms secondary to COVID-19.

Detailed Description

Axatilimab (SNDX-6352) is a humanized immunoglobin G4 monoclonal antibody with high affinity against colony stimulating factor-1 receptor (CSF-1R) under investigation for the prevention or treatment of respiratory signs and symptoms secondary to COVID-19.

This was a Phase 2, randomized, double-blind, placebo-controlled, multicenter study to evaluate the efficacy, safety and tolerability of axatilimab as an add-on to SOC therapy in hospitalized participants with respiratory signs and symptoms secondary to COVID-19 compared to SOC treatment.

Eligible participants were to be randomized in a 1:1 ratio to 1 of 2 treatment groups, active or control. All participants were to receive axatilimab or matching placebo intravenously (IV) as an add-on to SOC on Day 1, within 8 hours of randomization and on Day 15. Participants were to be followed for at least 28 days (+3 days) after the first dose of study intervention (Day 29).

The primary objective of the study was to assess the proportion of participants alive and free of respiratory failure at Day 29.

Study Timeline

• Study First Submitted: 2020-05-29
• Study Start: 2020-05-30
• Study First Submitted QC: 2020-06-02
• Study First Posted: 2020-06-04
• Primary Completion: 2020-07-13
• Study Completion: 2020-07-13
• Status Verified: 2022-06
• Results First Submitted: 2022-06-29
• Results First Submitted QC: 2022-06-29
• Last Update Submitted: 2022-06-29
• Results First Posted: 2022-07-22
• Last Update Posted: 2022-07-22

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 1

Inclusion Criteria

Type of Participant and Disease Characteristics -

1. Documented or confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by an FDA-approved polymerase chain reaction test of nasopharyngeal swab or stool less than 72 hours before randomization

2. Hospitalized for COVID-19

3. Illness of any duration with at least 1 of the following:

   1. Clinical assessment (evidence of rales/crackles on exam) and peripheral capillary oxygen saturation less than or equal to 94% on room air, or

   2. Requiring mechanical ventilation and/or supplemental oxygen, or

   3. Radiographic evidence (chest x-ray or computed tomography scan) of 1 of the following:

      • Ground-glass opacities, or
      • Local or bilateral patchy infiltrates, or
      • Interstitial pulmonary infiltrates

4. If the participant was intubated, must have been intubated less than 24 hours prior to randomization

   Sex and Contraception Guidelines -

5. Contraceptive use by men or women should have been consistent with local regulations regarding the methods of contraception for those participating in clinical studies.

   Informed Consent -

6. Capable of giving signed informed consent or by a designated representative, which includes compliance with the requirements and restrictions listed in the informed consent form and in this protocol

Exclusion Criteria

Medical Conditions -

1. Active bacterial pneumonia defined: based on either lobar consolidation on x-ray, positive sputum cultures, or leukocytosis with a left shift

2. Known active tuberculosis

3. Participants with acquired immune deficiency syndrome

4. It is not in the best interest of the participants to participate, in the opinion of the treating Investigator.

5. In the opinion of the investigator, progression to death was imminent and inevitable within the next 24 hours, irrespective of the provision of treatments.

6. Female participants who were pregnant or breastfeeding or expecting to conceive within the projected duration of the study, starting with the screening visit through 90 days after the last dose of study intervention

   Excluded Prior/Concomitant Therapy -

7. Prior treatment with other agents with actual or possible direct acting anti-inflammatory activity against SARS-CoV-2 in the past 30 days (for example, chloroquine, hydroxychloroquine)

8. Treatment with convalescent plasma

9. Treatment with high doses of corticosteroids (greater than 20 milligrams daily, prednisone equivalent) prior to randomization

10. Treatment with immunomodulators including anti-interleukin (IL)-6, anti-IL-6 receptor antagonists, or with Janus kinase inhibitors in the past 30 days or plans to receive during the study period

11. Previous exposure to study intervention or any other agent targeting colony stimulating factor-1 or CSF-1R or known allergy/sensitivity to study intervention

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Axatilimab (SNDX-6352)	SNDX-6352	Axatilimab on Days 1 and 15, IV + SOC
Placebo	Placebo	Matching placebo on Days 1 and 15, IV + SOC

Primary Outcome Measures

Name	Time	Method
Count Of Participants Alive And Free Of Respiratory Failure At Day 29	Day 29	Respiratory failure was defined by need for mechanical ventilation, extracorporeal membrane oxygenation, non-invasive ventilation \>6 liters oxygen/minute, or clinical diagnosis of respiratory failure with initiation of none of these measures only when clinical decision-making was driven solely by resource limitation.

Secondary Outcome Measures

Name	Time	Method
Change From Baseline At Day 15 In Biomarkers Following Treatment With Axatilimab	Baseline, Day 15	The change from baseline at Day 15 in serum concentrations of interleukin 6 and c-reactive protein or hospital discharge or death is evaluated.
Count Of Participants Experiencing Adverse Events And Serious Adverse Events	Baseline through Day 29	This outcome measure evaluates the safety and tolerability of axatilimab within the same population. A summary of all serious adverse events and other adverse events (nonserious) regardless of causality is located in the 'Reported Adverse Events' section.
Count Of Participants With Secondary Clinical Improvement Outcomes At Day 29	Day 29	Participants achieving a ≥2 category improvement on a 7-point ordinal score relative to the baseline on Day 28 as collected on Day 29 are reported.
Change From Baseline At Day 29 In Oxygenation In Hospitalized Adults With Respiratory Signs And Symptoms Secondary To COVID-19 Treated With Axatilimab	Baseline, Day 29	The change from baseline at Day 29 or hospital discharge or death, if sooner, in the ratio of peripheral hemoglobin oxygen saturation to fraction of inspired oxygen is evaluated.
Time To Clinical Improvement	Baseline through Day29	The time to clinical improvement is defined as a national early warning score of ≤2 maintained for 24 hours.
Count Of Participants Requiring Ventilation Support	Baseline through Day 29	Participants who required initiation of mechanical ventilation after study entry are analyzed.
Count Of Participants Considered Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) Free By Day 15	Day 15	This outcome measure evaluates the antiviral effects of axatilimab in hospitalized adults by Day 15 or hospital discharge, whichever was sooner, with recently diagnosed SARS-CoV-2 infection.
Pharmacokinetics: Serum Concentration Of Axatilimab And Anti-drug Antibodies	Day 29	The serum concentration of axatilimab and presence of anti-drug antibodies is evaluated.

Trial Locations

Locations (2)

HonorHealth; 🇺🇸 Scottsdale, Arizona, United States

Montefiore Medical Center; 🇺🇸 Bronx, New York, United States