Poly-ICLC to Prevent Respiratory Viral Infections A Safety Study

This study will examine the safety of an experimental medication called Poly-ICLC, developed for preventing or reducing the severity of infections from influenza and other viruses acquired through the nose, mouth and lungs. The study is divided into two parts, in which Poly-ICLC is tested at different dose levels. Healthy people between 18 and 70 years of age who have no chronic medical problems may be eligible for this study. Participants undergo the following procedures: Part I * Up to 7 days before Poly-ICLC administration: Medical history, physical examination and blood tests. * Day 1: Nasal wash and Poly-ICLC administration. A small amount of salt water is placed into the front of the nose and then suctioned out. Poly-ICLC is then squirted into each nostril, one after the other, at a dose of 0.25, 0.5 or 1 mg. A small number of subjects are given a placebo (a solution with no active ingredient.) Subjects are observed in the clinic for 30 minutes after treatment. * Day 2: Subjects receive a second nasal wash and repeat blood tests. They keep a diary card for 1 week, recording any drug side effects. * Day 5: Subjects have repeat blood tests and a review of their diary card. The keep a diary card for another 3 weeks. * Day 12: Subjects are contacted by phone to review their diary card. * Day 28: Subjects are contacted by phone to review their diary card. Part II * Up to 7 days before Poly-ICLC administration: Medical history, physical examination and blood tests. * Day 1: Nasal wash and Poly-ICLC administration. Same as above for Part I participants. * Day 3: Subjects receive a second dose of medication and are observed again for 30 minutes. * Day 4: Subjects receive a second nasal wash and repeat blood tests. They keep a diary card for 1 week, recording any drug side effects. * Day 7: Subjects have repeat blood tests and a review of their diary card. The keep a diary card for another 3 weeks. * Day 14: Subjects are contacted by phone to review their diary ca