Influenza Vaccine in Pregnant Women

Influenza is a significant cause of morbidity and mortality in the United States (US), resulting in an average of 226,000 hospitalizations and 36,000 deaths each year. Pregnant women and infants are at an increased risk for the complications of influenza. Severe disease, emergency department visits and hospitalizations occur frequently in pregnant women and infants which are considered high risk populations. In the US, routine vaccination with inactivated trivalent influenza vaccine (TIV) is recommended for pregnant women or those who deliver during the influenza season. Few studies exist on the safety and immunogenicity of administration of seasonal inactivated TIV despite long-standing recommendations. Although influenza vaccination has been recommended during pregnancy, the rates of immunization remain low, at about 13 percent. This is a multi-site randomized, double-blind clinical trial in 200 ambulatory, medically stable 18-39 year old, inclusive, pregnant women in their second or third trimester of pregnancy (from 14 weeks of gestation to term, inclusive). Study subjects will be randomized 1:1 to receive one dose of a 2008-2009 seasonal inactivated TIV, either Fluzone® or Fluarix® (100 pregnant women per vaccine group). Once enrolled, a blood sample will be collected and each subject will receive a single 0.5 mL dose of a 2008-2009 seasonal inactivated TIV, either Fluzone® or Fluarix®. The vaccination will occur on Day 0. Subjects will be observed for approximately 15 minutes after vaccination. All subjects will maintain a memory aid recording oral temperature, and systemic and local adverse events (AEs) for 7 days after each vaccination. Subjects will be encouraged to take their temperature around the same time each day. Subjects will have a phone call on Day 2 for review of memory aid, concomitant medication assessment, and assessment of AEs. Subjects will have a phone call on Day 8 for AE assessment, concomitant medication assessment and review of memory aid. At approximately Day 28 after the vaccination, subjects will return to the clinic for immunogenicity blood sample collection, concomitant medication assessment, and assessment of any AEs. A targeted physical exam will be conducted, if indicated. At approximately Day 180 or 6 months after vaccination, subjects will have a phone call for assessment for any serious adverse events (SAEs). Unsolicited non-serious AE data will be captured Day 0 through Day 28. Maternal SAE data will be captured throughout the study period (Day 0 through Day 180, approximately 6 months after dose of vaccine). Maternal and infant SAE data will be collected when obtaining data on pregnancy outcome. Serum for immunogenicity evaluations will be obtained prior to the dose of vaccine (at Day 0); and one month after vaccination (at Day 28). Pregnancy outcome data will be captured by a review of medical records and a phone call to the subject. Data include any complications during labor and delivery for both the mother as well as the neonate, to include premature delivery or delivery by emergency cesarean section. Neonatal assessments will include but not be limited to gestational age, birth weight, Apgar scores, congenital abnormalities, infection, hematological and metabolic complications, admission to nursery or Neonatal Intensive Care Unit and the need for respiratory support. Blood samples collected will be tested in a central laboratory for the levels of hemagglutination inhibition (HAI) and microneutralization (MN) antibodies.

Inclusion criteria

• Pregnant female between the ages of 18 and 39 years, inclusive.
• Is from 14 weeks of gestation to term, inclusive.
• Is in good health, as determined by vital signs (heart rate <100 bpm; blood pressure: systolic <140 mm Hg; diastolic less than or equal to 90 mm Hg; oral temperature <100.0 degrees Fahrenheit), medical history to ensure stable medical condition and a targeted physical examination based on medical history (if indicated). A stable medical condition is defined as health outcomes of the specific disease are considered to be within acceptable limits in the last 3 months.
• Able to understand and comply with planned study procedures.
• Provides written informed consent prior to initiation of any study procedures.
• Agrees to sign medical release for herself and her infant(s) to allow study staff to gather pregnancy outcome data, if needed per clinical site policy.

Exclusion criteria

• Receipt of the 2008-2009 seasonal influenza vaccine [trivalent inactivated vaccine (TIV) or Flumist] prior to enrollment into the study.
• Has a known allergy to eggs, egg proteins, latex allergy or allergy to other components in the vaccines (i.e. formaldehyde, polyethylene glycol p-isooctylphenyl ether, sucrose, gelatin, polysorbate 80).
• Has a history of severe reactions following immunization with contemporary influenza virus vaccines.
• Has received any other licensed vaccines within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) prior to vaccination in this study or expects to receive a licensed product prior to Visit 4 (Day 28 visit) (except for inactivated influenza vaccine which may be received 2 weeks post vaccination with study product). Measles, mumps, rubella vaccine is permitted post-partum.
• Has a moderate-to-severe acute illness and/or an oral temperature greater than or equal to 100.0 degrees Fahrenheit, within 72 hours prior to vaccination. (This may result in a temporary delay of vaccination).
• Immunosuppression as a result of an underlying illness or treatment, or use of anti-cancer chemotherapy or radiation therapy within the preceding 36 months.
• Has an active neoplastic disease, a history of any hematologic malignancy, current bleeding disorder, or taking anticoagulants.
• Long term use of oral or parenteral steroids, high-dose inhaled steroids (>800 mcg/day of beclomethasone dipropionate or equivalent) within the preceding 6 months (nasal and topical steroids are allowed) or has received steroids for treatment of pre-term labor during this pregnancy.
• Has a history of receiving immunoglobulin or other blood product (with exception of Rhogam) within the 3 months prior to vaccination in this study.
• Has a diagnosis of a current and uncontrolled major psychiatric disorder.
• The subject is receiving listed psychiatric drugs (aripiprazole, clozapine, ziprasidone, haloperidol, molindone, loxapine, thioridazine, thiothixene, pimozide, fluphenazine, risperidone, mesoridazine, quetiapine, trifluoperazine, trifluopromazine, chlorprothixene, chlorpromazine, perphenazine, olanzapine, carbamazepine, divalproex sodium, lithium carbonate or lithium citrate). Subjects who are receiving an antidepressant drug and are stable for at least 3 months prior to enrollment without decompensating are allowed enrollment into the study.
• Known active human immunodeficiency virus, hepatitis B, or hepatitis C infection.
• History of alcohol or drug abuse in the 1 year prior to enrollment.
• Has a history of Guillain-Barré syndrome.
• Has a seizure disorder or is on an anti-seizure medication for a seizure disorder.
• Has received an experimental/investigational agent (vaccine, drug, biologic, device, blood product, or medication) during this pregnancy prior to enrollment, or expects to receive an experimental/investigational agent prior to Visit 4 (Day 28 visit).
• Has an acute or chronic medical condition that, in the opinion of the investigator would interfere with the evaluation of responses (this includes, but is not limited to: known chronic liver disease, significant renal disease, transplant recipients, uncontrolled diabetes, juvenile diabetes (Type 1) or advanced diabetes with renal and eye disease; diabetes controlled by diet or oral agents is acceptable).
• Has any condition that would, in the opinion of the site investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol.