Study of an Investigational Monoclonal Antibody, VIS410, in Subjects With Uncomplicated Influenza A

This is a Phase 2a randomized, double-blind, placebo-controlled study designed to assess the safety and tolerability of an investigational monoclonal antibody, VIS410, in subjects with uncomplicated influenza.

Subjects will be admitted to an infusion unit for drug administration and observation following infusion. The study is designed to compare an infusion of a single high or low IV dose of VIS410 against placebo. Subjects will be followed for 100 (±7 days).

Eligibility Criteria:
Inclusion Criteria:

* Male and female subjects aged ≥18 years and ˂65 years
* Women should fulfill one of the following criteria:

  1. Post-menopausal; either amenorrhea ≥12 months or follicle stimulating hormone \>40 mIU/mL (milli-international units/milliliter) as documented in their medical history
  2. Surgically sterile; hysterectomy, bilateral oophorectomy, or tubal ligation
  3. Women of childbearing potential participating in heterosexual sexual relations must be willing to use adequate contraception from screening until 60 days post infusion
* Non-vasectomized (or vasectomized less than 6 months prior to dosing) male subjects who have a female partner of childbearing potential must use an effective birth control method when having heterosexual intercourse, from screening until 60 days post infusion
* Test positive for influenza A by Rapid Antigen Test performed with a commercially available test on an adequate nasopharyngeal specimen in accordance with the manufacturer's instructions
* Presence of at least one respiratory symptom (cough, sore throat, or nasal symptoms) of moderate to severe intensity, or presence of at least one constitutional symptom (myalgia \[aches and pains\], headache, feverishness, or fatigue) of moderate to severe intensity
* Onset of symptoms (time when the temperature was first measured as elevated \[temperature of ≥100.4°F or ≥38°C\], OR the time when the subject experienced at least one respiratory symptom or at least one constitutional symptom) no more than 72 hours before the start of infusion

Exclusion Criteria:

* Use of NSAIDs or antihistamines within 6 hours of study drug dosing with the exception of those used as part of the pretreatment regimen
* History of intolerance or allergic response to monoclonal antibodies and/or pretreatment medications (diphenhydramine, ibuprofen and acetylsalicylic acid)
* Subject weight less than (\<) 45 kg
* Subjects with clinical history that would lead to increased risk of influenza complications including but not limited to clinically significant cardiac disease, moderate to severe asthma, or other moderate to severe chronic obstructive pulmonary disease, metabolic syndrome including moderate to severe diabetes or active tuberculosis
* History of chronic GI disease, including bleeding, ulceration, Irritable Bowel Syndrome, systemic mastocytosis or chronic diarrhea
* Women who are pregnant, breast-feeding, or considering becoming pregnant
* Patients with hypoxemia requiring oxygen support
* Clinical evidence of worsening of any chronic medical condition (temporally associated with the onset of symptoms of influenza) which, in the Investigator's opinion, indicates that such finding(s) could represent complications of influenza
* Presence of immunocompromised status due to chronic illness, previous organ transplant, or use of immunosuppressive medical therapy including systemic steroids
* Presence of known Acquired Immune Deficiency Syndrome-defining illness, chronic hepatitis B or hepatitis C
* Receipt of any dose of antiviral therapy such as, but not limited to, rimantadine, amantadine, peramivir, zanamivir, laninamivir or oseltamivir in the 7 days prior to screening
* Enrollment in any other investigational drug or device study, any disease or vaccine study within 30 days prior to Day 1 or within 5 half-lives of the investigational compound, whichever is longer
* Subjects unable to take oral predose medication
* Known or suspected alcohol or drug abuse, that is, abuse of a level that would compromise the safety or cooperation of the subject in the opinion of the Investigator
* Subjects on chronic medications where the dose has not been stable for at least 3 months