TC-6987 for the Treatment of Mild to Moderate Asthma

Asthma is a common, chronic inflammatory disorder of the airways that affects an estimated
20 to 22 million people in the United States. It is characterized by variable and recurring
symptoms, notably airflow obstruction, bronchial hyperresponsiveness, and an underlying
inflammation. The bronchospasm is caused by inflammation of the muscles surrounding the air
passageways, making them smaller, thus more difficult for air to freely move in and out of
the lungs. Cardinal symptoms of asthma include coughing, chest tightness, shortness of
breath and wheezing. These symptoms are often more severe in the morning and late night,
and usually reversible with medications. Clinically, asthma is typically classified
according to the frequency of symptoms, forced expiratory volume in 1 second (FEV1), and
peak expiratory flow rate.

The rationale for this Phase II proof of concept study is to demonstrate that TC-6987
improves respiratory function in subjects with asthma, compared to placebo, as measured by
the Baseline FEV1 on Day 1 compared to the End-of-Treatment FEV1 on Day 28 or Early
Withdrawal (EW); and also to assess the safety and tolerability profile of TC-6987 in
subjects with asthma.