Study Evaluating the Safety and Efficacy of MN-221 as an Adjunct to Standard Therapy in Subjects Experiencing an Acute Exacerbation of Asthma

This is an international, randomized, double-blind, placebo-controlled, multi-center ED
study. Each subject will receive MN-221 or placebo administered through a continuous
intravenous infusion in addition to the standardized treatment for an acute exacerbation of
asthma.

Upon presentation to the ED for assessment and treatment for an acute exacerbation of asthma
the patient should receive standard of care consistent with the international guidelines
(e.g., Global Initiative for Asthma [GINA] or the National Asthma Education and Prevention
Program [NAEPP]) and required, in part, by this protocol prior to screening procedures
being performed.

Prior to any study specific treatment or evaluation being performed a subject must have
signed an IRB/EC/REB approved consent form. Once the subject has received the initial
treatment regimen the subject will be assessed for response to the treatment including
spirometry.If the subject meets all entry criteria the subject will be randomized to receive
MN-221 or placebo. Throughout the screening process the subject will continue to receive
standardized treatment consistent with the appropriate guidelines for the treatment of acute
exacerbations of asthma.

Subjects enrolled in the study will receive an intravenous 1-hour infusion of MN-221 study
drug or placebo. Subjects receiving MN-221 will be administered a total dose of 1200 μg.

During the study treatment period, the subject may continue to receive standardized
treatment and be assessed. The study treatment period will be approximately 3 hours in
length. Safety and efficacy will be monitored throughout the treatment period. PK
parameters (if applicable) will be obtained from subjects at selected study sites. A blood
sample for genomic evaluation will be collected during the treatment period (at
participating sites) if the subject consents to the evaluation. An initial 24-hour
post-randomization follow-up visit will be completed to evaluate the subject's health status
as well as for safety and PK parameters (if applicable). A second follow-up contact will be
completed by telephone seven days post-randomization for safety purposes and to evaluate the
subject's health status.

A periodic risk/benefit evaluation will be performed by the study's Data Safety Monitoring
Board.