The study will be conducted at three sites: Vanderbilt University Medical Center (Lead site), Cincinnati Children's Hospital Medical Center (contributing site), and Duke University Medical Center (contributing site) during the 2018-2019 influenza season. Participants will be randomized 1:1 to receive either a single intranasal dose of licensed quadrivalent LAIV (LAIV4) or an intramuscular injection of quadrivalent IIV4 (IIV4), stratifying by asthma severity (mild vs. moderate-to-severe). Vanderbilt will enroll about 100 participants, Cincinnati will enroll about 110 participants, and Duke will enroll about 90 participants. After enrollment, participants will be followed for 43 days via 5 additional phone, email, or text visits to monitor systemic reactogenicity, asthma symptoms and exacerbations, and serious adverse events. The primary objective is to compare proportions of participants with asthma exacerbations during the 42 days after LAIV4 versus IIV4. Because of the potential for increased risk of wheezing after LAIV, the use of LAIV in persons with asthma has been an area of vaccine safety research for many years; the safety issue remains unresolved. A clinical study to assess the safety of LAIV4 in children with asthma could expand the evidence base and inform clinical decision-making and public health policy.
This is a prospective randomized, open label clinical trial in approximately 300 children aged 5-11 years with a physician diagnosis of persistent asthma. Participants will be randomized 1:1 to receive either a single intranasal dose of licensed quadrivalent LAIV (LAIV4) or an intramuscular injection of quadrivalent IIV4 (IIV4).